Review of High Z Materials for PSI Applications T. Tanabe, N. Noda and H. Nakamura

N I F S 1 5 2 NIFS—152 J P 9 2 1 1 1 2 4 JP92111Z4

R evlewo lgbZ a t e r l a l sf o rP SIA p p l i c a t i o n s Review offH High ZM Materials for PSI Applications

T T 四 a t 陪.N .N oda皿 dH N 此国別問 T..Tanabe, N. Noda and H..Nakamura ( R I 目e i v e d-A p r .3 0 .1 9 9 2 ) (Received - Apr. 30, 1992) 同 1 5 2 N I NIFS-152

四 .1 9 9 2 J Jun. 1992

・

T This h i sr report e p o r lw was as p prepared r e p a阻 da as sa a p preprint r e p r i n to offw work ork p performed e r f o r r n e da as sa a c collaboration o l l a b o r a l i o r r e s e a r c ho h eN a t i o n a lI n s t i l u t ef o rF u s i o nS c i e n c e( N I F S )o a p a n .百 l i sd ocumenli s research offt the National Institute for Fusion Science (NIFS) offJ Japan. This document is i n t e n d e df o ri nfom 旧l i o no n l ya n df o rf u t u肥 p u b l i c a t i o ni na o 町 田I a f l e rs omer e a r r a n g e intended for information only and for future publication in aj joumal after some rearrange­ 町 l e n l so l sc o n l e n t s ments offi its contents. I n q u i r i e sa b o u tc o p y r i g h ta n dr e p r o d u c t i o ns h o u l db d d悶 s s e d1 h eR e s e a r c h Inquiries about copyright and reproduction should bee a addressed to0I the Research .Japan. J a p a n . I n f o r m a l i o nC e n t e r .N a t i o n a lI n s l i t u l ef o rF u s i o nS c i e n c e .N agoya4 6 4 01 Information Center, National Institute for Fusion Science, Nagoya 464-01,

R eviewo i g hZ a t e r i a l sf o rP S IA p p l i c a t i o n s Review offH High ZM Materials for PSI Applications TelsuoT ANA8EJ， N obuakiNODA NODA2a RdH i r l 回 NAKA 品fVRA3 Tetsuo TANABEl, Nobuaki and Hiroo NAKAMURA 2

3

1 e p a r t m e l l l{ グN u c l e a rE l Ig ; l I e e r ; l Z g，F a c u l r yo l Ig i n e e r i n g， ' D Department of Nuclear Engineering, Faculty offE Engineering, O sakaU l l i ¥ ' e円 I t y ・ ，Y amada-okaS u i t a，O saka5 6 5 .J a p a l l Osaka University, Yamada-oka Suita, Osaka 565. Japan

2 a/i ol Z a l l l l s l i l l l l ef o rF u s i o l lS c i e l l c e .F u/'Oc h o .C h i k u s a k l t， 2N National Institute for Fusion Science, Furo-cho. Chikusa-ku. N a g o y l l4 6 4 .J a p a l l Nagoya 464. Japan

3 Japan Atomic Energy Research Institute, Naka Establishment, α ，' P ( ( 1 1A lom;cE l 1 e r g yR e . f e a r c hb w i l l l t e .N a . μIE s t a h l i . f h m e n r . 3J Naka. Iharaki 511-01. Japan N a k a . l h a r a k i3 1 1 0 1 .J apan

A n v i t e dp a p e ri 0 t hl n t e r n剖 i o n a lC o n f e r e n c eo lasmaS u r f a c eI n t e r a c t i o n sin i n Anni invited paper inn1 10th International Conference onnP Plasma Surface Interactions C o n t r o l l e dF u別 onD e v i c e sh e l di o n l e r e y .C a l i f o r n i a，f r o mM arch3 p r i l3 . Controlled Fusion Devices held innM Monterey. California, from March 300・- A April 3,

1992, to0b beep published in Journal offN Nuclear Materials. 1 9 9 2，and 皿d ¥ u b l i s h e di nJ o u r n a lo u c l e a rM a l e r i a l s .

A bstract Abstract

A p p l i c a l i o no a r b o nb a s e dl owZ a t e r i a l st oP FMh a ss i g n i f i c a n t l yi m p r o v e d Application offc carbon based low Zm materials to PFM has significantly improved plasma parameters in large tokamaks. There are, however, serious concerns off owever ，s e r i o u sc o n c e r n so p l a s m ap a r a m e t e r si nl a r g el o k a m a k s . T h e r ea r e，h erosion, neutron damage etc. for application off l low Z m materials in future D-T e u l r o nd amagee l c .f OT a p p l i c a l i o no owZ a l e r i a l si nf U l u r eD -T e r o s i o n，n

b u r n i n gm a c h i n e .T oa p p l yh i g hZ e l a l s1 0P FM，t h e r ea r es e v e r a li s s u e s1 0be b e burning machine. To apply high Zm metals to PFM, there are several issues to solved; high Zi impurity production by sputtering , I their accumulation in plasma Ie r i n g， h e i ra c c u m u l a l i o ni np l a s m a s o l v e d ;h i g hZ m p u r i l yp r o d u c l i o nb ys p ul center, and high radiation loss. Because offI these concerns high Zm metals are ，a n dh i g hr a d i a t i o nl o s s . B e c a u s eo h e s ec o n c e r n sh i g hZ e t a l sa r enot n o t c e n t e r widely employed nor planned to be used in the present large tokamaks. Since our w i d e l ye m p l o y e dn o rp l a n n e d1 0b eu s e di nt h ep r e s e n ll a r g el o k a m a k s . S i n c eo u r efforts have been concentrated to optimize the low Zm materials , I little systematic it t l es y s t e m a t i c e f f o r t sh a v eb e e nc o n c e n t r a t e dt oo p l i m i z et h el owZ a l e r i a l s， investigations for high Zm materials in tokamak have been done, lacking data base i n v e s t i g a t i o n sf o rh i g hZ a t e r i a l si nl okamakh a v eb e e nd o n e，l a c k i n gd a l ab a s e especially those concerning the impacts onnp plasma core. e s p e c i a l l yI h o s ec o n c e r n i n gt h ei m p a c I so l a s m ac o r e 町 f u t u r e， m a t e r i a lp r o p e r t i e sr e l a t e d In order to employ high Zm material as PFM near future, material properties related I no r d e r1 0e mployh i g hZ a t e r i a la sP FM田

1 0i m p u r i l yp r o d u c t i o na n dh y d r o g e nr e c y c l i n ga r er e v i e w e da n dd i s c u s s e dw h a ti s to impurity production and hydrogen recycling are reviewed and discussed what is i m p o r t a n ta n dw h a ts h a l lb ed o n e . important and what shall be done.

吋 s:: D iv e r t o r ， G r a p h i t e， Hydrogen 問 c y c l i n g ， HighZ, Z， I m p u r i t i e s， Lo wZ, Z . [Key words wo [Key Divertor, Graphite, Hydrogen recycling, High Impurities, Low

Molybdenum, Review, Sputtering/Tungsten] Molybdenum， Review，S p u t 低r i n g， T叩 I g S 蜘]

1 .I ntroduction 1. Introduction 児 2 e a r . 、( ' 0 町 p lasmap a r a m r l e r sh a ¥ ' ch c c ng r c 3 t l yi m p r o ¥ ' c d i I n r h e In these 200y years, core-plasma parameters have been greatly improved inn

、 ， w a l lm a t e r i a l sh a 、 ' cg r c a t l yi n f l u e n c c dt h ep c r f o r m a n c co a g n c t i c a l l y confined o n f i n e d wall materials have greatly influenced the performance off a a magnetically

t okamaks a nd a c h i cedt h o 日 c Ol l 1p a r a b l et u引 onr et じt or .I ti c l lk nownt h a t tokamaks and achieved those comparable tooa af fusion reactor. It is父 w well known that l l 1

じ

p lasmai a c hc x p e r i l l l c n t a ld c v i c c .P a同i c u l a r l y .a d o p t i o no ，同 Zm a t e r i a l s .s u c h plasma innc each experimental device. Particularly, adoption off1 low Z materials, such

assc carbon, boron and berrylium have led tooa a g great success innt the present large a a r b o n .b orona ndb c r r y l i u mh a ¥ ' el e dt r c a ts u c c e s si h ep r e s e n tl a r g e tokamaksU]. These experiences and the achievement have been quite important too ' ，e x p e r i c n c c sa ndt h ea c h町、l e m c n th a ¥ ' ch c e nq u i t ci m p o r t a n tt t o k a m a k s [1 ) .T hes

。 問

make a g great contribution toot the fusion-research history. Nevertheless itri is quite m akea r e a tc o n r r i b l l t i o nt h ef u n r e同 a r c hh i s t o r y . N e ¥ ' c r t h e l c s si sq u i t e clear Ihat there slill remain a l lot off吋 questions and works tooc establish the fusion u e s l i o n sa ndw ork詩 t s t a b l i s hr h cf u s i o n c l e a rt h a tt h e r es l i l lr c m a i na o to reactor. r c a c t o r l l 10 nga l l .f o l l o w i n gI woa r cmo ぉ1 d i f f i c u l l1 < 了 o l ¥ ' c di nI h cn e x ts t e po h e A Among all. following two are most difficult to0b be s solved in the next step offt the

f u s i o nr c s c a r c h : h ow1 ainl 1 li nI h ch i g hI c m p e r a r u r cp l a s l l l 山 間 l c a d ys l a r e . fusion research: how to0m maintain the high temperature plasmas in as a steady slate,

出 。

and how long are life times various structures including the plasma facing a nd h ow l o n ga r cl i f cl i m off¥ ' a r i o uぉ s l r l l c t u r c si n c l l l d i n gl h cp lasma f a c i n g c omponcnt叫PFC) a g a i n引 n c u l r o ni r r a d i a t i o no r i g i n a t c dt -T b u r n in g . U componcnts(PFC) against neutron irradiation originated byηD D-T burning. Uppt too

、

a' eh cenじ o n c e n t r a t i n go u rc f f o r tぉ t p t i l l l i z cl h ec a r b o nb a s e dl owZ Z n o ¥ v .川 now, we h have been concentrating our efforts tooo optimize the carbon based low

、

、 TThis h i si isso off

sf romaaviewpoint lCWpOm¥t oma 引m izet h cc o r eplasma p 1出 map a r a m c ¥ e r m a l e r i a¥ materials from to maximize the core parameters.

course onnt the line along the historical requirement for the fusion development. c o u r s co h el i n ea l o n gl h ch i s l o r i c a lr e q u i r e l l l e n lf o rl h ef u s i o nd e ¥ ' e l o p m e n r 00 h eo t h e rh a n u .s y s l c m a l i c川 、e S l i g a l i o n so i g hZ ‘ l l c r i a l sh a ¥ ' eb een On t the other hand, systematic investigations onn h high Z m materials have been

lacking, which results very poor data base for Ihem. especially those onnt the 川町 r yp oord a l ab a s cf o rl h e m .e s p e c i a l l yt h o s eo h e l adinιw hich r c s u l l矢 in impacts to0t the plasma core. InnI ITER design, graphite based low Zm material iss じt s1 h ep lasmaC l l T C . I TERd 出 i g n .g r a p h i t cb a s c dl owZ a t e r i a li I mpa recommended to0b bee u used as t the divertor plates and first wall protection for the 日 d山 h ed i ¥ '町 t o rp l a t e民 a ndt i r s tw a l lp r o t e c t i o nf o rt h e r ecommenucd1 initial operation phase in toom minimize the risk offp plasma contamination. At[t the t n山川 o p e r a t i o np h 山 . :i norder ord~r t inimizcl h er i s ko lasmac o n l a m i n a t i o n .A h e same time, however, it i is envisaged that the development and testing offp plasma 岨 met i m c .h o帆 引 c r . i t se n v i s a g e dt h a tt h cd c ¥ ' c l o p m c n ta ndt 目 l i n go lasma facing components including high Z m materials should beec carried out during the f a じIngじ omponcntsi nc ¥ l Id i n gh i g hZ a t c r i a l ss h o u l d b a r r i c do u td u r i n gt h e physics phase | 22ト |. I Inn S SSTR (Steady State Tokamak Reactor)[3], inn w which STR ( S t e a d yS t a t eT okamak R e a c t o r l [ 3 ) .i hich p h y s i c sp h a s e1 engineering feasibility is a t top priority, a h high Z m material, such Mo. is日 t the e n g i n e c r i n gf e a s i h i l i l ); Sl : ' o pp r i o r i r ) - a i g hZ a t e r i al.日以 : h出as M o.i h e 町

primary candidate of the armor tiles because high erosion ratel4] and loss of1 l ft h ca rTl10 rt i l出 b e c a u同 h i g he r o s i o nr a l c l 4 1a nd 1 0日 0 p r i m a r yc a n d i d a tC' l

、

thermal conductivity^.Ci| of' the carbon based material enforce the frequent り1 5 < ) 10 1l h cc arbon b a s c dm a l c r i a le n f o r c ct h cf r e q u e n t t h e r m a lc onduじ1 l replacement offt the armor. which very hard from engineering aspect[3.7J. placem、i1to h ea nnor.w hich阿is v e r yh a r df rome n g i n e e r i n ga s p e c t l 3 . 7 j

陀

、

O o u r 叩 r c c c n ta da nじ 目 。offc a r h o nh a s c um a t e r i a ls u c ha sぞ / Cc ompo 引 t ew hich Offc course recent advances carbon based material such as C/C composite which h a sv c r yh i g ht h c r m a lc o n d u c t i ¥ ' i t ) 'a nd h i g hl h e r m a ls hock r e s i s r a n c e .i s¥ ' e r y has very high thermal conductivity and high thermal shock resistance, is very

- 1ー

p r o m i s i n gt c d u cl.! 叩r f a c cI c m p c r a l l l r c .h u ld 1 0 1h c l pI h cu c g r a d a l i o nl l fI h c n n a l promising toor reduce surface lemperalure. hul doo1 n»i help Ihe degradation of thermal ( ln C l l l m ni r r a d i a l i ol 1I X .l J . l S a f c l yp mhlcmo ca ndi l sI l l W c o n d u c l i v i l yd ucl conductivity due to neutron irradiation |8, )|. Safety problem offB Be and its low l

山川 c a nn l l lh ca v o i < ! c d .! o O1 1 0 1 . T h u . sW a n n o lp u lI O ( ) l kr c l i a n どCυn m e l l i n gp melting point can not be avoided, too 110|. Thus weCじ cannot pul 100'/? reliance on

low Z m materials for a r future machine, even though systematic investigations on l owZ a t e r i a l sf o ra u t u r c m a c h i n e .c vcnt h o u g hぉ y S l c m a t lじ 川 V山 u g 叫 I O n s0 1 1 high Z l materials have been lacking, which results in very poor data base for ihem. h i g hZ l 1a t e r i a l sh a v ch ccnl a c k i n g .w hichr c メu l l討 1 1 1v c r yP O ( 汀 d a l ah ‘凶 cf o rI h c m . especially those onnt the impacts toot (he plasma core. c s p e c i a l l yI h o 民eo h ci l l 1p a c t st h cp l a s m ac o陀 F romm a t e r i a la s p c C I .戸地 U C l i l i t ya nds m a l lI h c r l l l a ls h o c kr c s i叫 叩 印 刷 cd1 From material aspect, poorrd ductility and small thermal shock resistance u.sed to0 b beea ap problem rohlemn offl most I lo S 1o offl the h erefractory refra~tory m metals. c t a l札 R Recent c c c n ta advances d v a n c c sj innp production r o d u c ti o na and nd

p u r i f i c a l i o nt e c h n i q u c so h cr c f r a clOr ym C l a l sh avc l owcrcd d u c t i l ch r iU lc purification techniques off t the refractory metals have lowered ductile brittle

transition temperature (DBTT) offm molybdenum (Mo), for instance, far below room l 1p e r a t u r c( DB1 T)o olyhdcnul l 1( Mo)‘f o ri n s l a n c c .f a r悦 h 、 官 C l l l Wr ( ， ) om 1 t r a n s i t i o nt el temperature 111.12). This means I 阻 emper 悶a l 加 u r ，陀 c1 1 1 . 1 口 2 / . T h i sl l 1 e ι t that it is now possible to machine Mo at room

、、

t 悼 e m p e r a t u r ， 陀 ec a s i l y副 a n 叫 dh i g hZ 討 h ccom lmgw l 叫 t h i nc n g i 川n c c r i n gf 山 c 山 ‘ a 討 引i b i l i l yf ， “ ' or P F C . temperature easily and high Z 阿is becoming within engineering feasibility for PFC. a c i n gt h en ewp h a s co h cr c s c a r c hh i s t o r y .w h o u l dn pcno l l rc y c s T hus f Thus, facing toot the new phase off t the research history, wecs should open our eyes 噌

toob broader possibilities than toot those inn t these 10 years, including both low Za and t r o a d e rp o s s i b i l i t i e st h a nt h o s ei h c s c1 0y e a r s .i ndudingb o t hl owZ nd high Z m materials assP PFM. This is the basic idea offt this review, in w which questions hichq u c s t i o n s h i g hZ a l e r i a l sa FM. T h i si st h eh a s i ci d e ao h i sr c v i c帆 川 and prospects offt the high Zl materials are summarized assw widely assp possible. l 1a t c r i a l sa r es Ul l 1m a r i z e da i d c l ya o s s i b l c . a ndp r o s p e c l so h eh i g hZ v i e w sw hichp a r t l yd i s c u s sh i g hZ m p u r i t yh e h a v i o ra ndp r o h l e m s S e v e r a ln i c e問 Several nice reviews which partly discuss high Zi impurity behavior and problems

have been published [1,13-15]. A l lot offi indication and suggestions from these h aveb eenp u b l i s h c d[ 1 . 1 3 1 5 ] . A o to n d i c a t i o na nds u g g e s t i o n sf rom t h e s c reviews are reflected innI the present paper. v l e w sa 町 r e日e C l c di h ep r e s e n lp a p e r .

問

2 xperimentson ighZ aterialsi okamaks 2..E Experiments on h high Zm materials innt tokamaks a lp r o h l e mf o rh i g hZ l 1 a l e r i a l st e t F i r s t l y .I c tu e v i e ww halh a v eh ecnt h e陀 Firstly, let ussr review what have been the real problem for high Zl materials toog get a oodp a r a m e t e ro h ep lasmac o r ei nf u 日o nd e v i c c s ag good parameter offt the plasma core in fusion devices. 目

O neo h em ainp r o b l e mo i g hZ l 1 a t e r i a li si l l 1p a c to a d i " t i o n1 0 日 o on日ned One offt the main problem offh high Zl material is impact offr radiation loss onnc confined p l a sl l 1a .I r d c rt t i s f yt h eb u r n i n gc o n d i t i o n .i t a sT c enr e p o r t e d( 1凸1t h a tt h e plasma. Inno order too同 satisfy Ihe burning condition, it h has been reported [I6| that the c o n c e n t r a t i o no i g hZ o n sa h cp lasmaa x i smu ぉth ch clow 1 0 t h o u l dh c concentration offh high Z i ions atlt the plasma axis must be below 10 "4. . I It s should be 4

noted that this issa ac calculated prediction and there are not much experimental data n o t e dt h a tt h i討 i a l c u l a t c dp r c d iじt i o na ndt h c r ea r cn o lm uchc x p c r i m c n t a ld a t a which indicate quantitatively the concentration limit required. The central density w hichi n d i c a t eq u a n t i t a t i v c l yt h cc o n c c n t r a l i o ni I m i tr c q u i r c d . T hcc c n t r a ld cn ぉI t y offi impurity ions depends on their generation rate atl I the surface ofrp plasma facing o m p u r i t yi l l l l Sd c p c n d s0 1 1t h c i rg c n c r a t i o nr a l ca h cぉ u r r a ι c" l a 日刊誌 f a c i n g component, shielding effects byyc edge plasma, inward llowtdegree of' accumulation) c omponcnt，s h i c l d i n gd TcじI sh d g cp l a s m a .i n w a r dt l o w ( d c . g r c c0 1m xul l 1u l a l i o n )

i n s i d et h ep lasma c o r e ，< 1 ( ' . inside the plasma core etc.

I tm ay b e c e剖 a r yt c la omprchf :n s i v c It may bee n necessary too g gel a c comprehensive

e a c ha l u t i o n .F rmna r a c t i c a lp o i n t0 1v i e w . u n d e r s t a n d i n go a c hp r o c e附 t understanding onne each process toor reach a叩 solution. From ap practical point of' view, t h el i n a lg o a lo h es t u d i e so i g hZ m p u r i t i c si s1 nowI h cI h r c s h o l dl i the final goal offt the studies onnh high Zi impurities is to0k know the threshold limit l l 1i l ν value a l u e o i g hZ o nc o n c e n t r a t i o na b o v ew hichD -Tb u r n i n gc o u l dn o tb esustained, u s t a i n c d .a n d加 1 O offh high Zi ion concentration above which D-T burning could not be and to ー ，

v e 吋砂 f ' ' ‘ yo p e r a t i o n a l印 c 【 0 叩 m 剛 n 川 叫 d i t i 川 < > . 叩 m 出拙 s加 t og u a r 問a n t 阻 e eI 日 I 川 I n p u 叩r 口 川 l Iyc ∞ < > ) 川 1 叩 肌 n 川 I C 叩: verify operational conditions to guarantee impurity concentration below this limit. B

2 . 1 .A ccumulationo ighZi m p u r i l i e si . 制Jdc o n l i n e m e n ls chemes 2-1. Accumulation offh highZ impurities inng good confinement schemes

O neo h es e v e r e s tp r o b l e m sw i t ht h eh i g hZ m p u r i t i e si st h c i ra c c u m u l a t i o ni n aa One ofit the severest problems with the high Zi impurities is their accumulation in

core plasma inna ag good confinement scheme. In 1982, ag good confinement scheme cor'~ p l a s m ai oodc o n f i n e m e n ts c h e m e . I n1 9 8 2 .a o < > dc < > n f i n e m e n ts cheme called "H-mode" was found in ASDEX| 17J. This was firstly obtained with titanium b l 剖 n e dw i t hl i l a n i u m c alkd" H-mode"w asf o u n di nA SDEXfI7 ].T h i sw asr ir rp l a t e sa nd s t a i n l e s ss t e e lw a l l [ 1 7， difficulty tooa access the H-mode with medium Z o orrh high Z w wall. However, the d i f f i c u l t yt c c e s st h cH m < > d ew i l hm cdiumZ i g hZ a ll . H owevcr.t h e accumulation of metal impurities innt the plasma occurs during the quiescent H町 i h ep l a s m ao c c u r sd u r i n gt h eq u i出 c e n t H a c c u m u l a t i o n< > fm c t a li m p u r i t i phase, which leads tooI the termination offI the H-Mode[19|. In Fig. 1l time traces off hichl e a d st h et c r m i n a t i o no h eH M o d e f I 9 1 . I nF i g .1 ill1el r a c e so p h a s e，w several plasma parameters are plotted for ann H H-mode discharge innJ JFT-2M[20). s e v e r a lp lasmap a r a m e t e r sa r ep l o l l e df o ra -moded i s c h a r g ei FT-2Mf20J. where most offt the wall and divertor plates are covered byyt titanium (Ti) because off w herem osto h ew a l la n dd i v e r t o rp l a t e sa r ec o v e r e db i l a n i u m( T i )b e c a u s eo the repetitive application offT Tiig gettering. One can clearly see continuous increase t h er e p e l i t i v ea p p l i c a t i o no e t t e r i n g . O nec a nc l e a r l ys e ec o n t i n u o u si n c r e a s e offt the radiation offT Ti innt the H-mode, which finally results innr returning to0I the L旧t i o no ii h eH r n o d e， w hichr i n a l l yr e s u l l si e l u r n i n g1 h eL o h er a d mode. In JET, ittw was reported that nickel impurities are confined longer time innt the m ode. I nJ E T .i asr e p o r t e dI h a tn i c k e li m p u r i t i e sa 陀 c o n f i n e dl o n g e rt i m ei h e H-mode than innI the L-mode (see H -modet h a ni h eL -mode( s e eFig.2)[21]F i g . 2 ) [ 2 1 ] . T hea c c u m u l a t i o no o n g e rc o n f i n e m e n to m p u r i t i e sh a sb e e no b s e r v e da l s oi The accumulation orrl longer confinement offi impurities has been observed also inn

other good confinement scheme, such assc counter injection offn neutral beam (NB) o l h e rg oodc o n f i n e m e n ts c h e m e .s u c ha o u n t e ri n j e c t i o no e u l r a lb e a r n( NB) heating innI ISX-B[23], pellet fueling, and improved ohmic confinement(IOC)[22]. h e a t i n gi S X B [ 2 3 ] .p e l l e tf u e l i n g .a ndi mprovedo hmicc o n f i n e m e n t ( I O C ) [ 2 2 ] All these examples suggest that the good energy-confinement scheme is always A I It h e s ee xampless u g g e s tt h a tt h cg oode n e r g y c o n f i n e m e n ts cheme i sa l w a y s accompanied byyi impurity accumulation with longer confinement time, which is the a ccompaniedb m p u r i t ya c c u m u l a t i o nw i t hl o n g e rc o n f i n e m e n tt i m ew hichi st h e 宅

severest constraint for the application offh high Z materials toQP PFC. s e v e r e s tc o n s t r a m t品 o rt h ea p p l i c a t i o no i g hZ r n a t e r i a l s( F C . I h o u l db e‘h owever，s t r e s s e dt h a tt h 日 p r o b l e mi si r r e s p e c t i v et h eZ umber Itts should be, however, stressed that this problem is irrespective toot the Zn number

t a sn o ty e tb e e nc i e a rh ow l o wZ m p u r i t i e si n d u d i n gh e l i u m( H e ) o m p u r i t i e s . I offi impurities. It h has not yet been clear how low Zi impurities including helium (He) g e n e r a t e db -Tb u r n i n gi n O u e n c eo u s t a i n i n ga oodc o n f i n c m e n ts c h e m e . In I n generated byyD D-T burning influence onn s sustaining ag good confinement scheme. T EXTOR i a sb e e ns hownI h a tH o n sa r cm nfincdm uchl o n g e r川 h eH r n o d e TEXTOR, itth has been shown that Heei ions are confined much longer in I the H-mode 司

t h a ni h cL m o d e I 2 4 ] . A 同 時n tt h em aximumc o n c e n t r a t i o no ct o l e r a b l ef o r than innt the L-mode|24]. Attp present the maximum concentration offH He tolerable for c o n t i n u i n gD -Tb u r n i n gi l c a u ys t a t cH -modei sn o ts 。 じclear. I c ar . T hust h cf u c l continuing D-T burning inn" as steady state H-modc is not so Thus the fuel - 3 3 -

d dilution i l u t i o nb byyH Heea and n dl low owZ Z i impurity m p u r i t yp problem roblema are r ep parallel a r a l l c l吋 questions u eぉt i o n st toot the h eh high i g hZ Z

impurity accumulation inn g good confinement schemes and should bee s .solved i m p u r i l ya c c u m u l a l i o ni o o < !c onfincmenl s chemes a nd s h o u l db o l v e d simultaneously. s i m u h a n e o u s l y . M anye f f o r t sh a v cb e e np a i dt e tt h es t e a d ys t a t eH -modc. I nD f I I-D‘ 10 1 0 Many efforts have been paid toog get the steady state H-mode. In Dlll-D, s e c .H -modeh a sb e c na c h i c v e db a r e f u lc o n t r o lo dgcl o c a l i7.edm odc(ELM) sec. H-mode has been achieved byyc careful control offe edge localized mode(ELM)

instability[25]. InnJ JFT-2M, ergodization attt the edge offt the confinement region t i o na h ee d g co h cc o n f i n c m e n tr e g i o n i n s l a b i l i t y [ 2 5 ] . I FT-2M.field f i e l dc r g o d日 a i v i n ga u a s i s t e a d ys l a l eo h e HHh a sp r e v e n t e dt h ei m p u r i l ya c c u m u l a t i o n、 g has prevented the impurity accumulation, giving a q quasi-steady state offI the

Mode[26]. M o d e [ 2 6 ] . M OSIo h c s ee f f o r t sp r c s e n t l yc a r r i e do u ta r eu n d c rl owZ FMc o n d i t i o n s Most offt these efforts presently carried out are under low Z P PFM conditions a nda 0 l u l i o nw i l hl owZ ay n O Id i r e c l l ya p p l i c a b l ct h eh i g hZ . S l i l lb i g and a 5 solution with low Z m may not directly applicable tooI the high Z. Still big

question has remained unsolved , I that is, how plasma confinement would bee h a li s .h owp lasmac o n f i n c m c n l w nuld b q u e s t i o n h a sr emaincd u n s o l v c d、 influenced iffP PFM was completely changed from low Z1 to0h high Z. Wagner ella al.[27| i n f l u e n c c di FMw ， 凶 c o m p l c t c l yc h a n g c df r o ml owZ i g hZ . W agncrc . l[ 2 7 1 clearly showed the difference in the confinement time between SS and Bo of divertor 1 1c n tl il 1 1 cb c t w c c nS Sa n dB rd i v c r t o r c l e a r l ys howcdt h ed i f f c r c n c ci nt h ec o n f i n cl walls in ASDEX "H-mode" giving belter confinement for B. But such comparison 1 1o d c "g i v i n gb c t t e rc o n日ncmcnt f n rB . B u tぉ u c hc o l 1 1p a r i叩 n w a l l si nA SDEX" H -l is very difficult because the change of" the material automatically introduces ft h cm a l c r i a la UlOm a l i c a l l yi n l r o d u c e s i sv e r yd i f f i c u hb e c a u s ct h cc hangc o different impurities and SS often works as a叩 source offl low Z i impurities assC C u r c co owZ m p u r i t悶 お おsuch u c ha d i f f e r e n ti m p u r i t i e sa n dS So f t e nw orksa sa and O a ass d discussed inn s sec3-2. i s c u s s e di ed-2. a nd0

Therefore the comparison must be done well T h c r c f o r ct h ec omparison m ust b cd one w e l l

characterized orrd diagnosed condition. c h a r a c l c r i z e do i a g n o s e dc o n d i t i o n T hu sI h eq u e s l i o n sa r e叫 mmarizeda s( 1 )w h c l h c ri o s 日b l eo n tt e laa Thus the questions are summarized as (1) whether itt凶 is p possible orrn not toog get l O cments chemew i t hh i g hZ FM. " " di o 日 i b l ct h c n s t e a d ys t a t ci nodc onf steady state inna ag good coniincment scheme with high ZP PFM and iffp possible, then 句

噌

( 2 )w h c l h e rI h ch i g hZ m p u r i t yc o n c c n t r a t i o nC ' I Ob c l lb elnwt h ea l l o w a o l el i m i t (2) whether the high Zi impurity concentration can becw well below the allowable limit h es t e a d ys t a t cc o n d i t i o na n d( 3 )h owp l a ぉmap a r a m e t e r sw ouldb 0 0 d i f i c di in t the steady state condition and (.1) how plasma parameters would bee1 modified iff

叩

P FMw asc o m p l e t c l yc hangedf r o ml owZ i g hZ PFM was completely changed from low Zt tooh high Z.

・2 .S t e a d ys t a l ec o n c e n t r a l i o no i g hZ m p u r i t i e si no hmica nd" 1λnode" 2 2-2. Steady stale concentration offh high Zi impurities in ohmic and "L-mode"

d i s c h a r g e s . discharges.

T he< lo s o l u t ed c n ぉi t yo o n c c n t r a t i o n( ) fh i g hZ m p u r i t i c si h c刈 c a d ys t a t eLL The absolute density orrc concentration of high Zi impurities innt the steady state

: g c si sa c p a r a t cq l l c s1 Il l l lf r o l l lt h ci m p u r i l ya c c uTnu l a t I o ni nt h cg ood m odcd i s c h a r modc discharges is as separate qucslion from the impurity accumulation in lhe good c o n f i n e m c n ts c h c m c . confinement scheme. H c l lk n o w l lt h a tm c t a l i m p u r i t yc o n c c n l r a t i o l ls t r o n g l yd c p c n d so lasma It 目 is w well known that metal-impurity concentration strongly depends onnp plasma d e n s i t y .p lasmac u r r e n t .n c u t r a lb eam( NB)p o w e r .w orkingg a so i s c h a r g ca n d density, plasma current, neutral beam (NBI power, working gas offd discharge and

- 4 4 -

d i v e r t o r / l i m i t e rc o n f i g u r a t i o n s . I a b l e1 r es ummarized t h em easured divertor/limiter configurations. Inn t table 1 a are summarized the measured c o n c e n t r a t i o n so e t a li m p u r i t i e si h ec e n t r a l問 g i o no l a s m a s .M osto h ed a t a concentrations offm metal impurities innt the central region offp plasmas. Most offt the data a r ef o rt h eo hmicd i s c h a r g ea n ds c a r c ef o rt h eNB e a t e dd i s c h a r g e .F i g u r e3 hows are for the ohmic discharge and scarce for the NB h heated discharge. Figure 3s shows a y p i c a le xample o b t a i n e di n0 1 1 1 0 [ 2 8 ] . a t typical example obtained in DIII-D[28].

N i c k e lr a d i a t i o nd e c r e a s e sa sI h e Nickel radiation decreases as the

d e n s i l yr i s e sa nd I h a tf o rt h e o p e n d i v e r l o rd i s c h a r g ei sa l m o s lo neo r d e ro density rises and that for the open-divertor discharge is almost one order off

magnitude lower than that for the limiter discharge. The density dependence is m a g n i l u d el o w e rI h a nt h a tf o rI h eI im i l e rd i s c h a r g e .T hed e n s i l yc l e p e n d e n c ei s attributed to0 t the edge temperature[29,30]. 30 ] . a t t r i b u l e d1 h ee dge t e m p e r a t u r e [ 2 9.

Itt i is particularly important to I sp a r t i c u l a r l yi mponanl 1 0

investigate the correlation between measured concentration and edge temperature. i n v e s l i g a l et h ec o r r e l a t i o nb e t w e e nm easuredc o n c e n l r a t i o na n de d g el e m p e r a l u r e . However, itli is very hard toof find a r report onns simultaneous measurement offt these H owever.i sv e r yh a r dt i n da e p o r to i m u l t a n e o u sm easuremento h e s e quantities, tffi ittw would beea allowed to compare edge temperature data byyE Erents ell q u a n l i l i e s . [ ouldb l l o w e d1 0c omparee d g et e m p e r alU陀 d a l ab r e n t se a/.(31], weec could put Te eLCFS= = 1 120 eVVf for JET case in the table 1. But there is noo a l . [ 3 1 ] .w o u l dp u tT 2 0e o rJ ETc a s ei nI h et a b l e1 .B u tt h e r ei sn L C F S

means to guess the edge temperature for other cases. m eans1 0g u e s st h ee d g el e m p e r alUr ef o ro l h e rc a s e s . O nee x t r e m ec a s ei si n c l u d e di h et a b l e .I h a li s .I h el o w e rd e n s i l yd i s c h a r g ein i n One extreme case is included innI the table, that is, the lower density discharge A l c a t o rC [3 2 ) T heMo e n s i t yi se x l問 melyh i g he v e nw i l hI h ee l e c t r o nd e n s i l ya s Alcator C[32]. The Mo d density is extremely high even with the electron density as 9m h i g ha .3 .o hichr e 田 o ni sn o tc 1e a r . [ nI h日 p a r l i c u l a rc a s e 、e l e c t r o n high ass7 7x x 1 10 01 m"-\ offw which reason is not clear. In this particular case, electron 目

19

l e m p e r a l u r e s howed h o l l o wp r o f i l eb e c a u s e o h es t r o n gr a d i a l i o nl o s sa h e temperature showed hollow profile because offI the strong radiation loss atlI the p lasmac e n t e r [ 3 3 ) . plasma center[33]. S uch h o l l o wt e m p e r a t u r cp r o f i l e sw ereo h s e r v e di t u n g s l e n( W) Such hollow temperature profiles were observed innORMAK ORMAK ( (tungsten (W) l i m i t e r l [ 3 4 1 .P LT(W a nd s t a i n l e s ss l e e l( S S )l i m i l e r )[ 3 5 . 3 6 )a nd O ITE(Mo limiterl[34], PLT(W and stainless steel (SS) limiler) (35,36] and DITE(Mo

limiter)[37|. This has been one offt the most important reason for excluding the high a sb e e no neo h em o s ti m p o r t a n tr e a s o nf o re x c l u d i n gt h eh i g h l i m i l e r l [ 3 7 ] . T h日 h Za as PFM. However, one should note that the hollow priofile could be avoided by a Z sP FM. H o w e v e r .o nes h o u l dn O l cI h a tI h eh o l l o wp r i o f i l ec o u l db ea v o i d e db ya little stronger gas puffing after Ti gettering|36]. Itt i is also noteworthy that the I it t l e日 l r o n g e rg a 民 p u f f i n ga f t e rT ig e t t e r i n g ] 3 6 ] . I sa l $ on O l e w o r l h yt h 剖 t h e hollow profiles are observed mostly innl low density discharges. Figure 4 shows two h o l l o wp r o f i l e sa r co b s e r v e dm o s t l yi owd e n s i t yd 同c h a r g e s .F i g u悶 4s howsI wo profiles offe electron temperature in PLT with SS limiter|36]. The hollow profile l e c l r o nt e m p e r a t u r ei nP LTw i l hS Sl i m i t e r ] 3 6 ) . T heh o l l o wp r o f i l e p r o f i l eぉ o (Fig.4(a)) is without current contraction during start up. while the central-peaked ( F i g. 4 ( a ) )i sw i l h o u tc u r r e n tc o n t r a c t i o nd u r i n gs t a r tu p .w h i l et h ec e n t r a l p e a k e d profile (Fig.4(b)) with contraction which could bee p provide byy s special p r o f i l e( F i g. 4( b ) )w i l hc o n l r a c t i o nw hich c ould b r o v i d eb p e c i a l preprogramming offg gas puffing. p r e p r o g r a m m i n go a sp u f f i n g・ T h e r ci sn c u b lI h a l叫 c ha i g hr a d i a l i o nl o s sm usl b v o i d e di u t u r e There is nood doubt that such a h high radiation loss must beca avoided inn f future

machine. All example above introduced show that the hollow profiles could bee e ds howI h a lI h eh o l l o wp r o f i l e sc o u l db m a c h i n c .A I Ie xamplea bovci n l r o dlJc a v o i d e db d o p t i n gh i g h e rd e n引 t yo p e r a t i o n s .H owcvcr.i sa g出 nn o lc 1e a rw hal avoided byya adopting higher density operations. However, itti is again not clear what i sI h cc r i l i c a lc o n d i l i o n .n e yp a r a m c l c r1 v o i ds u c ha i g hc o n c e n t r a l i o no is the critical condition, orrk key parameter to0a avoid such a h high concentration off

metals. m e l a l s

- 5 5 -

A o l cl l fl i g h li J l l l 'u r i l i山 刊isはanother n o l h e fI l l l p o r t山 l tI ' I! > . U C叶 Il ll ' t a l川 】p U r l l !川 早川 A r role of lighl impurities important issue ot" metal impurin origin. O ncl l fl h cc x p c r iじ町ピ W 出 r c p or[c di JFT.~I 司 XJ. i . . . . . h i c hMo a d i a t i o nd 広 町 山 山i One of the experience was reported innJFT-2|.^H], inn¥ which Mo r radiation decreased

one order offm magnitude correlating with oxygen reduction due lo0礼 application of1 o ne o r d c ro agniludc l 'o n c l a t i n . g¥ . . ' i l h0 人y g c l lr e J u c t i o nd uc 1 p p l i仁a t I n n0 titanium gettering. This .suggests that oxygen play a d dominant role of" the . .I h a lO X)耳目1p l‘ . l } 'a l l m i n a n t r ok 0 1t h c Mo M l l r i t a n i u mg e u e r i n g . T h i ss uggCSI r e l e a s ca h el i m i t c rぉ u r f a c c . release atl I the limiter surface.

、

P o s p i c s / .l'ly kc .l l .， O I h a' Ci n d i仁川 cd l a r g c Pospies/.c/.yk ett a al.|.>0] have indicated large

。

contribution offC C、O O叩 and/or metal lo0I the .sputtering yields of Cr Va and Fe. in c o n t r i b u l i ol 1o d / o rI 1 1 C I1 I11 h c' p u l l c r i n gy i e l d s( ) fc l 1dF ι observed h S C f ¥ '山 ji l 1 TEXTOR. Since the sputtering yields byyt the impact of' oxygen orrc carbon is m much T EXTOR. S i n c cI h es p u t t e r i n gy i c l d sb h ci m p a c t0 1o xygcl 1o a r o ol 1日 uch larger, and the threshold energies lower than those byyd dculcrium, these low Z l a r g c r . a nd I h cI h r c s h o l dc n c r g i e sl o w c rI h " nI h o 引: I > c u l C r i ul11. I h c四 l owZ impurities should have large contribution to0I the production of the metallic impurities. 1l r i b u l i o n1 h cp r o d l lじl i o n! lf t h cm c t a l l i ci m p u r i t i c 札 i m p u r i l i c ss h o u l dh avel a r g cc Ol Inno ohmic discharge offJ JET, Ni influx from graphite tile to0 I the plasma has been I hmicd i s c h a r g eo ET 、N i i n t l u xf romg r a p h i l el i l e/ h cp lasmah a sb e CI 1 attributed too s sputtering origin, though itl i is not clear which species among a t t r i b u t c dt p u t t c r i n go r i g i n .t hough i sn o tc 1c a rw hidl s p c c i c su mong deuterium, carbon and oxygen is the main cause.(39| d e u t e r i u m .c a r b o na nd l l x y g c ni st h cm ainc a u叩 . 1 391 U n l i ln owd i a g n l l s l i c sf o rP S Ih a v c .u n f o r l l l n a l c l y，n o lh c cl 1C I 1υ ugha nds l ll 1 lc t i m c s Until now diagnostics for PSI have, unfortunately, not been enough and sometimes

impurity production due to0p pyrolytic origin like ag gaseous desorption orrm material i m p u r i l yp r o d u c l i o nd uc1 y r o l y t i cl l r i g i nI ikca ascouぉ d c叩 r p l i o no a l c r i a l sublimation, which can beea avoided byyr reducing areal heal load with al technique such s u b l i m a t i o n .w hichc anb v o i d c db c d u c i n ga r c a lh c a ll o a dw i t ha e c h n i 4 u cs u c h like divcrtor swing[40], seems to0b beem mixed-up with that due toop physical sputtering. eems1 ixed-upw i l ht hmd uet h y s i c a ls p u t t c r i n g ・ l i k ed i v c r t o rs w i n g [ 4 0 ]‘ s The origin offc carbon bloom issn not finally identified due to0白 either radiation enhanced T heo r i g i no a r b o nb loomi o lf i n a l l yi d e n l i f i c dd ue1 山町 r a d i a l i o ne nhanccd sputtering orrI thermal sublimation[41]. Thus the origin off h high Zi impurity must bec s p u t t e r i n go h e r m a ls u b l i m a l i o n [ 41 ] .T husI h co r i g i no i g hZ m p u r i l ym ustb more carefully examined. m orec a r e f u l l ye xamined.

Anyhow reduction offI the light impurities issq quite A nyhow r e d u c l i o no h el i g h li m p u r i l i e si u i t e

important not only because offt their direct effect onnh burning plasmas through dilution, i m p o r t a n tn o to n l yb c c a u s eo h e i rd i r e c te f f e c to u r n i n gp l a s m a st h r o u g hd i l u t i o n . but also onns sputtering offh high Zi impurities. 1s oo p u t t e r i n go i g hZ mpu 同t l e s b u ta

2 ・ 3 .M elali mpu吋t i e sd uringI CRFh e a t i n g 2-3. Metal impurities during ICRF heating

A lthoughI CRFh e a l i n gi u c c c s s f u l l ya p p l i e d1 r e s e n ll o k a m a k s .i m p u r i l y Although ICRF heating isss successfully applied to0p present lokamaks. impurity

contamination has been one offI the severe problems offI this type offh heating. This Kピ hbI c o n t a m i n a l i o nh a sb eeno neo h es e v e r ep roblemso h i sI y p eo e a t i n g・ T partly because anna antenna issr required toob bec c close to0p plasma edge inno order to0g gel p anlyb c c a u s ea n t c n n ai e q u i r e dt 10 s e1 lasmac dgei r d e r1 c laa good coupling of' RF p power to0p plasmas. g oodc o u p l i n g0 1RF ower1 l a s m a s .

Asぉ i is well .summarized inns section 8.2 A sw e l ls ummarizcdi e c l i o nX . 2of 0 ' 1

ref.(l). there are experimental evidences that ap part of RF p power directly coupled r cf . J1 1 .I h c r ca r c山 p e r il l 1c n l a lc y i d cl1l'c SI h a la a r ll 1fRF l 1w crd i r e c l l y叩 u p l c d with scrape off plasmas and e-folding length inl particle flux is broaden byyRF RF p power w i t hぉ c r a p co f fp l a 町" "Sa nde f o l d il 1gI c n g l hi 1p a r t i c l cI l" xi sb r o a d c nb owcr with metal orrm metal contaminated limiters. These are probably reasons for stronger 出 e< Jr cp r o T a b J yr c a s o n sf o r川 r o n g e r w i t hr n c t a lο e l a lc o n t a m i n a t c t ll i m i l c r ' ¥ . T h interaction between plasma and antenna/limiters. It is noteworthy that, innじ contrast nda n l c n n a ! l i m i t e r ぉ hi sn o t e w o r thyt h a t .i o n l r a 叫 i n t e r a r t i o no c t w ( ' e np l a sl11i.l a

、

to0NB NB h heating, metal impurity did actually limit the plasma stability and parameters 1 c a l i口巴町Il 1c l a li m p u r i l yd i d" c l " " l l yl i l l 1i lI h cp l a ' n d u r i n gI CRド h e a t i n gw i t hI ¥VI c v e. lI nメspite pne川of a ( ) o dl ' o u p l i n g0 1

山

RF p power toot the plasma electrons, high Teeconditions could not he maintained for RF t l w c rt h cp l a sl 1 1aC I cC l r l l n s .h i g hT condilio l1~ l 'o u l dn o th cm u i n l a i n c df o r several tens inilli-second and the plasma was down byyl the strong radiation :u nda ndt h cp lasmav .込 %cooled 山 川I c dd l Jwnh t H . 's t r o n gr~ldiation s c v c r a lt C l l sm i l l i s cl loss. This problem could be solved only byyじ curboni/.ation[43|. l o s s .T h i sp roblemc O l l l db e附 I v e do l 1l yh a r h ol1i z a t i ol1[4 '[ A d d i t i o n a le f f o r tぉ m ighth 1 eeded t p p l yh i g hZ i t hI CRFh e a t i n g Additional efforts might bec l needed toO a apply high 2 PFM PFM w with ICRF heating S じh emec nmparcd1 t h c rh c a t i n gt c c h n i q u c s scheme compared to0o other heating techniques.

2 . 4 .E xperience; 2-4. Kxperience innJT-60 with TiC-coated Mo

I h ee a r l yp h a s co T f l O .T iCc o a t c dm olyhdcl 11 1 l t 1 (T iC/Mo)w asa d o p t e da Innt the early phase offJ JT-60. TiC coaled molybdenum(TiC/Mo) was adopted ass

I im i t e r sa ndd 刊 e r t o r s .a ndT iCc o a ¥ e di l 1c o n e l6 25a i 円 tw a ll . Mo ass e l e c t e d limilers and divertors, and TiC coaled inconel 625 assI first wall. Mo w was selected after various engineering R&D w work|44|. The dialing was manufactured byy CVD CVD a f t e rv a r i o u se n g i n e e r i n g R&D o r k [ 4 4 [ .T hec 山 l l f n gw 出 m anufaclUr e dh and PVD t techniques [45] with thickness off2 200m mm. a ndPVD e c h n i q u eぉ [ 4 5Jw i t ht h i c k n e同 o m 目

Inn見spite offt this coating, Mo I p i t co h i sc o a t i n g . Mo

burst was often observed, especially inn l iimiter operations both with hydrogen b u r s lw as o f t e no b s e r v c d .e s p e c i a l l yi i m i l e ro p e r a l i o川 h o l hw i l h h ydrogen discharge and helium one and divertor operations vi ith helium. This is found to0b bee d i s c h a r g ea nd h e l i u mo ne•. a ndd i v e n o ro p e r a ¥ i o n s" l hh e l i u n l .T h i si sf o u n d1 originated high heat toot the several o r i g i n a l e dfrom from extraordinary e x t r a o r d i n a r yh i g hh e a tflux 1，日 concentrated c o n c e n t r a t e dt h eedges e d g e sof o f5 e v e r a l TiC/Mo tiles. This problem was solved byy X X-point sweeping for divertor T iC/Mo I i l e s . T his p roblem w as s o l v e db -point s wecping f o rd i v e r t o r discharges, and more than 200M MW offNB NB p power was injected without the Mo b burst. d i s c h a r g e s .a ndm oreI h a n2 Wo owerw asi n j e c t e dw i l h o u ¥t h eMo u r s t Figure 5 s shows a t typical time behavior offr radiation powers with and without X-F i g u r e5 howsa y p i c a lt i m eb e h a v i o ro a d i a t i o np ower 句 w i t ha ndw i t h o u tX point swing.[46] p o i n ts w i n g . [ 4 6 ] O nceI h eb u r s tw ass u p p r e s s e d .o neo h ea d v a n t a g e so h eT iC/Mow a l lw as Once the burst was suppressed, one offt the advantages offI the TiC/Mo wall was I h a tt h eI O l a li m p u r i l yc o n c e n l r a l i o nw asq u i l el owa ndv a l u e so f fa r el ower that the total impurity concentration was quite low and values offZ Ze ff are lower e

t h a nt h o s ef o rc a r b o nw a l la d o p t e dl a t e ri T-60a howni i g . 6[ 4 7， 48 ] . T h i s than those for carbon wall adopted later innJ JT-60 asss shown innF Fig.6 [47,48]. This

iss b because off/ lower contamination offo oxygen and carbon impurities TiC nd c arhon i r n p u r i t i e s from from T iC i ecause o owerc o n t a m i n a l i o no xygen a s u r f a c e s .w hichc o u l db n l e r p r e t e da e s u l t so l a b l es u r f a c ec o m p o s i t i o nw i t h surfaces, which could beei interpreted assa ar results offs stable surface composition with

titanium carbide and oxide. t i t a n i u mc a r b i d ea ndo x i d e howt h a tT iC/Moa n d / o rp u r eMo o s s i b l ya v a i l a h l ci These experiences show that TiC/Mo and/or pure Mo 日 is p possibly available inn T hesee x p e r i e n c cぉ s

future iffe excessive heal flow can bec a avoided and heat flux isぉ r removed byy a ann f u t u r ei x c e s s i v ch e a t日 owc an b voided a nd h c a tl 1 u xi emoved b

ぉ 。

appropriate active cooling. They also that il p provides a p possibility off ' l C ya l s suggest u g g c s tt h a li t r o v i d c sa o s s i h i l i l yo a p p r o p r i a ¥ ea c ¥ i v ec o o l i n g . T smaller contamination with low Z I impurities. . tt I l ll1 w i t h! lw，，' Z m p u r i t i c s . s m a l l e rc ontamIn:

-

7 7 -

It should bee 1 noted here that I tぉ h o u l dh 1 0 1 c1 el. l ' 1

、

Mo nd V v ' f L ' l a i nI 1 lU ・ ' Lhless k 州訪 nmu川川 h)dro~('n a nda . . . a l u T a l i o n should h o u l dh Mo a and W retain much amount of hydrogen and a . saturation beo

、

a attained 1 l 訓n c d mu much じhI lower n w c rt fluences l u c n c c見 I than " ， nI the h og graphite. r " p h i l o . A Aho\e hooX SIIOK. I I I I K ." assd depicted c p iじ1 ( ' Uf from r n m I h c r m a l d 出 。 rplions pt ! t :t r a( F i g . 1 4. 1 l lo s tl l f1 1 1 ( 'T l ' l a i n c dh ) d r o g . . : ni sr dca 町 d thermal desorplion spectra (Fig.14 I. I most of the retained hydrogen is released

immediately after the beam ol'f|7H|. This indicates that one can expect only limited f J ] 7i !. 1T h iぉ i n d i仁川町 I h a l o n cじ 込nc x p e c lo n l yl i m i t c u i m m c d i a l c l ya f l c rI h ch camo wall pumping byyMo Mo 剖and W a and plasma must be operated atlh high recycling regime lp umpingb l dW n dp l出 mamu 日1h cl l p c r a l c da i g hr oりじ l i n gr c g i ml ' w a¥ even for a s short pulse. However, since the dynamic retention isぉ m much e venf o ra h or ¥p u l s c . H owever.日 n c et h cd ynamiじ r e t c n t i n n1 uch気smaller. m a l l c r density control may becc easier than the graphite. d e n s i t yc o n t r o lm ayb a s i c rt h a nt h cg r a p h i t c 町

H ydrogenr c c y d i n gu n d e rh i g hr ccydingr c g i r n ci c a l l yi m p οr ¥a n li s s u cf o r Hydrogen recycling under high recycling regime is封 ar a really important issue for n c 川 c nmingl o n gp u l s cm achinci r r c s p cじt i vl 'o aJ lT 1l叫 c r i a lぉ next coming long pulse machine irrespective offw wall materials.

F rmnt h i sr cぉp CL ' 1 . From this respect.

i ayn o tb c叫suitable i t a h l ct ompa 陀 g r a p h i l ca ndWIM 川出 FMd i r c c t l y .b c c a u討c ittm may not be tooc compare graphite and W(Mo| as P PFM directly, because

both reemission and reflection are quite different between them. Instead one can h o t hr c e m i s s i o na ndr c t l c c t i o na r cq u i t cd i f f c r e n th Clwccnt h c m . I n s l c a do n cc a n compare Nb o orrT Taaw with Mo o orrW W. because hydrogen rccmission innt the former is呂 c omparc Nb i t h Mo .b c c a u s ch ydrogcnr c c m i s s i o ni i l Cf o r m c ri similar toog graphite as馬seen innt the earlier work |93|. 田 m i l a rt r a p h i t e出 ecni h ee a r l i c rw ork1 9 3 1 . bee5 so0d different due toos similar Z n number. i m i l a rZ umber . b i f f e r e n td uet

while the reflection must not w h i l c t h cr c t l c c t i o nm ustn o t

Even though Nb a and Taam must not bee E vent h o u g h Nb ndT ustn o tb

used for the armor inna af fusion reactor, such kind offe experiment is quite necessary u s e df o rt h ea r r n o ri u s i o nr e a c t o r .s u c hk i n do x p c r i m e n ti sq u i t en e c e s 5 a r y not only for more comprehensive understanding offp plasma surface but intera~tion b u t n o to n l yf o rm orec omprehensiveu n d e r s t a n d i n go lasma5 u r f a c einteraction also for designing future machine. a l 5 0f o rd e s i g n i n gf u t u r em achine

S igh H eatL oadT esta nd M aterialB ehavior 5..H High Heat Load Test and Material Behavior U nderr e s e a r c ha ndd evelopmento FC f o rI TER.h i g hh e a tl o a dt e s to i g hZ Under research and development offP PFC for ITER, high heat load test offh high Z m e t a l sh a sb een e x t e n s i v e l yc onducted[94-98]. metals has been extensively conducted[94-98] .

1 .1 1 5 ] g ave a W hitely e Whitely etta al.|15] gave ann

r .S i n c em osl o h eh i g h e x c e l l e n tr e v i e wf o ra p p l i c a t i o no ighZ i v e r t o ra r r n o excellent review for application offh high Zt tood divenor armor. Since most offt the high l eh a v i n gp o o rw e J d a b i l i t ya ndh e n c el a c k i n gi h e r r n a ls h o c k Z e t a l sa r eb r iU Z m metals are brittle having poor weldability and hence lacking inn t thermal shock

resistance.[ 11.99.100], many efforts have been done tooi improve their ductility byy 叩 c c . [ 1 1 .9 9 . 1 0 0 ] . m anyc f f o r t sh a v eb e c nd onet mprovet h e i rd u c t i l i t yb r e s l s t alloying and/or purification! 11.12,100] and TZM i isso one offt the successful example. a l l o y i n ga ndforp u r i f i c a t i o n [ 1 1 . 12 . 1 0 0 ]a nd TZM n eo h cs u c c e s s f u Je xample Furthermore neutron irradiation increases the ductile brittle transition F urthermorc n eulron i r r a d i a l i o n i n c r c a s e s t h e d u c t i l c b r i t t J e t r a n s i t i o n temperature!DBTT) and earlier data shows neutron irradiation offa about la ndc a r l I c rd a l as howぉ n e u t r o ni r r a d i a l i o no b o u t t e m p e r a t u r e (DBTf

Idpa 1 dpa

rose DBTT offMo Mo ( over 500K. [101] Tfo ) v c r5 α l K . [ I OJ j r o s eDB R c c e n t l y日 n g l cじ r y ぉl a l l i n e" ndW p r o d u c c db i t h c r引sintering n t c r i n g[ 1 0 2 1o Recently single crystalline offMo Mo a and produced byyc either [102] orr FM. c J c c t r o nb camt l l c l t i n g l 6 6 1i sp r u p o s c dt cu t i l i z c d出 electron beam melting[b6| is proposed toob be ulili/cd as P PFM.

T hcDB Tfo h c The DBTT off t the

electron beam melted Mo(EB-Mo) is far below room temperature and large block c l e c t r o nb eamm c l t e dMo (EB-Mo) i sf a rh l ' lowr o 01 l 1I c m p e r alUr cu nd l a r g eb l o C K

，

o i n g l cc r y s t a l l i nC' i .T 1t 川。 a ¥ ' a i l a h l c l (. / f . F r o r nI h ee n g i n c c r i n g山uxpecl peCI. h l ' offs single crystalline is now availablc[o4f. From (he engineering . I the . 1ー-一] 11

a p p l i c a t i n n0 1t l l l '1 1 1 0 1 1 01 . 11 0 じkt F ぐ ¥ ¥ " i t ha oka " . ' l l l l l i l暗 ピchannel h 山 川0 1、 l 'c ms、 ( ! f ) application of' the monoblock tuuP PFC with ah hole assa a! cooling seems vers m cc f O fh l a z i n gl ) ra d h c s i o nt ot h en l l l l i n gh a s ci o t1 1 l'じ心山川、 nice, for blazing or adhesion to the cooling base is可 n not necessan. 句

H ighh e a tl o a dt 山 ti n di < :a t c! tI h川 t h es i n g ll'じれ叫 " l i i n eE R.v : l os hοwcdg 山>d High heat load test indicated that the single crystalline EB-Mo showed good

performance without appreciable cracks and recryslalli/ation. whereas polyp erformanec w i l h l l l l la p p r e cI < lhk c r aじk sa nd r e c r y s l a l l i z a l i o n .w hrfca持 p o l y . crystalline PM-Mo showed severe recrytalli/alion and intergranua! cracksloo] c r y s t a l l i n eP M-Mo s howed叫 、 ' ( ' n . : 'r C L T y tは l Ii l . at i l l l 1a nd i n t c昨 日nm 己c r a c k s [ o 6 ] 出as seen in Fig. 15(b). should be mentioned that the erosion offP PM-Mo byyh high s e e ni nF i g .1 5 ¥ h )目 I It ts h " u l! tb cm c n t i o n c dt h a lt h cc r 刷 i o no M-Ml1 h i g h heat load is four times larger than EB-Mo|103], presumably owing toop particle h e a ll o a di sf o u r t i m e sl a r g e rl h a nE B-Mo[IO川.p r c s u m a h l yo wingt a r t i d e emission from PM-Mo which originates from cracking off h boundary offl the e m i s s i o nf rom P M-Mo w hi < :h o r i g i n a t c sf r o r n c r a c k i n go oundary o h c recryslallized columnar grains asss seen in Fig. 15(b). Similar cracking is seen innt the r e c r y s l a l l il .e dc o l u r n n a rg r a i n sa e e ni nF i g . 1 5 ( b l . S i r n i l a rc r a c k i n gi ss c e ni h c heavily damaged divertor plates offT TiC/Mo in JT-60[ 104,1051. In recent our high h e a v i l yd amagcdd i v e r l o rp l a l e so iC/Moi nJ T 6 0 [ I 0 4 . 1 0 5 j .I nr e c e n lo u rh i g h heat load iest[661. single crystalline EB-W has also shown nice performance h e a tl o a dl e s l [ 6 6 ] .s i n g l ec r y s t a l l i n eE B-W h a sa l s os hown n i c ep e r f o r m a n c c without any cracks owing to recrystalli/.ation after once melting] w i t h o u la n yc r a c k so wing1 0r c c r y s t a l l i z a l i o na f t c ro n c cm c l t i n g (106]. 1 0 6 1

6 ecent R esultsi TP PE EMI ndTRIAM.IM ith 6.. R Recent Results innR RF FP P( (T - 1I RRM 15 5 )) a and TRIAM-1M w with M ooL imiter Limiter 1 )i m p u r i t yp r o d u c l i o na n da c c u m u l a t i o n， A sd i s c u s s e da b o v e .I h r e et o p i c si . e .( As discussed above, three topics i.e. (1) impurity production and accumulation,

(2)hydrogen recycling and material performance under load are main ( 2 ) h y d r o g e nr e c y c l i n ga nd(3) ( 3 )m a t e r i a lp e r f o r m a n c eu n d e rhigh I . ; g hheat h e a ll o a d a r em ain concerns for utilization offh high Z m melals assP PFM. Recently effect offMo Mo 叩 and e l a l sa FM. R ecenUye f f c c lo d c oncems f o ru l i l i z a l i o no i g hZ graphite limiter onnp plasma performance has been compared innR RFP(TPE-1RMI5 atl g r a p h i l el i m i l e ro lasmap e r f o r m a n c eh a sb e e nc omparedi FP(TPE-IRMI5a Electrolechnical laboratory innJ Japan). [66,73] E l e c t r o t e c h n i c a ll a b o r a t o r yi a p a n ) .[ 6 6 、 7 3 )

Because offt the extraordinary high B e c a u s eo h ee x t r a o r d i n a r yh i g h

heat load to0a a l limiter offt the RFP[66,73,107], surface temperature offI the graphite h e a ll o a d1 i m i l e ro h eR F P [ 6 6 . 7 3 . 1 0 7 ]，s u r f a c el e m p e r a l u r eo h eg r a p h i t e limiter increased over 2000K within ten milli-seconds, which made plasma I im i t e ri n c r e a s e do v e r2 000K w i l h i n t e nm i l l i s e c o n d s，w hich m ade p lasma operation very difficult. When the limiter materia) was changed from the graphite to o p e r a l i o nv e r yd i f f i c u l t W henl h el i m i l e rm a l c r i a lw asc h a n g e df r o mI h eg r a p h i t e1 0 Mo t the plasma confinement (electron density and temperature and loop voltage) I ta g e ) Mo h ep lasmac o n f i n e m e n l( e l e c l r o nd e n s i t ya ndl e m p e r a t u r ea ndl o o pv o was appreciably improved(examples for loop voltage are given innF Fig. 16). The 6 ) . T he w asa p p r e c i a b l yi m p r o v e d ( e x a m p l e sf o rl o o pv o l t a g ea r eg i v e ni i g1 improvement offt the plasma innI the RFP is m most probably owing tood decrease offI the i mprovemenlo h ep t a s m ai h eR FP日 ost p r o b a b l yo wingt e c r e a s eo h e limiter temperature[73,107] with anna aid offh higher thermal diffusivity. And higher l i m i l e rt e m p e r a t u r e [ 7 3，1 0 7 ]w i t ha i do i g h e rI h e n n a ld i f f u 引v i l y . A nd h i g h e r energy reflection coefficient offMo Mo I than that offc carbon could play some role. >ef f i c i e n to h a nI h a lo a r b o nc o u l dp l a ys omer o l e e n e r g yr e f l e c l i o n口 目

N c v e r t h e l e s s. hcnt h eh O Is p o tt e m p e r a l u r eo h eMo i m i t e rb ecomesn e a r Nevertheless .w when the hot spot temperature offt the Mo l limiter becomes near K .M o(1 )l i n ee m i s s i o ni n c r e a児 dd r a s t i c a l l y I h em e l l i n gp o i n lo r o u n d2 9似l the melting point offMo Mo a around 2900K. Mo(I) line emission increased drastically a ccompanyingo xygcna ndH i n c見 as 出 s howni nF i g .l 7 . accompanying oxygen and Haa l lines shown in Fig.17.

η 1 iぉ i n d i c a t 目 I h a l This indicates that

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O o

x x

5 6 7 7 8 8 J 9 3 ( O mr n: ) (I io , 9

3

F i g . 6 .C o m p a r i s o n0 f fi nJ T 6 0d i s c h a r g ew i t h2 0MeVN B Fig. 6. Comparison of1Z Ze in JT-60 discharge with 20MeV NB h e a t i n gf o rT i C / M oa n dg r a p h i t e ( 4 7 ) . heating for TiC/Moand graphite[47]. e f f

xx

3

#

X

*

0 ^

o v .

2

X

︿川

•

v

O

A°

X ×

N BI" '20MW NBI -20MW

A A

° o O

A

Li mi L im it t ee rr

X

×

O 0

A

hs

2 2

X

・

3 3

*

A

。 A

A

︿

4

J h h E ︿0 0 へ X

A

o

Lower X-point (Open divertor)

x

‘ AUXOOhoxxu 4x JKXO ︿ . ﹀ ハフ﹂匂 Q 9 .

6 6

C

X X

X X

10

，

T'Hg ， . .t W

TIIU'&et:Mo

・

E亀 ，p eri m .entalDitU o"t. Experimental Angle Q(a->ma/wn) A n & l e Symbol Symbol E^jeV) p:~~~生虫色旦 1 9 9 . O . 鈎0 .10-2 H 0 a 199. 0.800-10"* 1 1 7 . 0 O.tmO D 0 0 37-0 0.OM0

T-tget Proj'ectik 虫色_ Projed と "" M0 T~ Mo Mo

・

M < > Mo

・

6 3 . 0 6 0 . 0 60.0

・5.5.. 1

Mo Mo

h

-

n

・

C.I叫 . t ，.d n Calculated D. at t a. Target Projectile Symbol _\»f>fj Q(_tunu/ion) . o j 也t e_ -Angle Aßp;r~ r . i o固 } _Tu" p _e -i _f _ . . _ -Sy _mb _o _C_ E _. _.(.V) Q( „u _u _/ 2 01 . 回 匂 W T D • 129 0 0654 w M W W . . 0 3 2 . 2 32.1 w w

・

‘

0 . 0 5 6 0 O . M tO O.OH0

“

・ ロ ‘

1 6 . 0

hτ'E

仁3

-

10

_1

口

w

J

〉

ト

w

]

コ z

E

J

白

Z

< > :

l 斗 ト

・

E»peri_.e_ta[ D. at ta E l l p e τm e . . t . CO T a r&d Pi.j«lile P， o lO'tt i l e Angle Anp ;l e Symbol S， mb. ! ， F., . f . '. . ( . V ) Q (:r.仰向向 " 1 Tar_rt {tV) Q ) W 0 0， 700-10-1 D 00179 W W 30.S 53.0 3 0 . 1 1

ロ

Calcl . ll a t . :， JD Calculated D. at t aa T ・ 中 t Projectile P r o j e e l H e Angle An; r l e Symbol S y m . b o ¥ £,h(eV) E， ，( e V ) Q (. 初 四 向0 1 Target Q(»toro/ioo) Mo

一 一 一

H

E

foI

01

ト

コ 止

コ 止

( J )

[ f )

001

t . -

001

0001

ー 0001

01

10 I 10 [ NERGY ( keV) ENERGY CkeV)

100 100

1000 1000

10

01

Fig. 7 S Sputtering yield of1Mo Mo a and by various ions[54] F i g .7 pul 1e r i n gy i e l d0 ndW b yv a r i o u si o n s [ 5 4 ]

ヒN ト~RGY

(kc :V)

O

500 5 00

1000

一一「一一

o E

~

4 0 0

¥ w (9

Z

主-600 ιJ 〉

(9

0 : :

w

，/

Z-800

( ' ¥ ' o

" ， ¥ 1 . y

1 p

ry

w w

g

LL

O

500 1000 500 1000 TEMPERATURE/ TEMPERATURE/KK Fig. F i g .8. 8 .Free Free Energy Energyof 0 1Formation Formationof 0 1Various VariousOxide.[58] O x i d e . [ 5 8 ]

1 5 0 0 1500

U

内

・ コ

ZC

一 同

p=o*

υ {JF}ZOEU︽区比 Oω 。区︿工

18.5 keV H*-'Ta

B

L ↑ z一﹀OMLUZU 区凶amω ﹂υ一ト区︽n

﹄} ﹂ Dd ︽﹀区ω

i40 4 0

3 0 z 30

o

6

2 0 20

a

ID

>/'

o

1 0 a: 10 <

- - » . -Charged ("10)

i

o

。

2 2

4 4

6 6

8 8

o

10

12

V,

16

18

ARTICLESIkeV) I k e V ) E ENERGY NERGY O OF EMERGING PARTICLES FE MERGING P

2 0 20

・

Energy distributions d i s t r i b u t i o n s of 0 1l 1e u t r a l and a~ positively p o s i t i v e l yc h a r g e d Energy neutral charged hydrogen atoms backscattered from Taa b bombarded with 18.5-keV ; c k s c a t t e r e df rom T ombarded w i t h -1 8 . 5 eV h ydrogen a toms-b a p r o t o n s .T hec h a r g e df r a c t i o nN '/N'十 i v e nb o t s . protons. The charged fraction N"/N' +N N°。お is g given byyd dots. F i g .9 .H ydrogenR e f l e c t i o nf romT a ( 6 9 ] Fig. 9. Hydrogen Reflection from Ta[69]

，

︼口品

E NERGY-REFLECTraN C aEFFICIENT R ENERGf-REFLECTION COEFFICIENT R,

目白

Eコ

Cコ

口

口

zm 円 X

H可

+ 問 円 一 羽 田 門 的Z

o m↓U 由 同

U A m 円 uw回 門 凶 ﹃

-口凶

cl

口日

ZEbmx 勺

門

。四月白同問H u ﹃

h v

d ロ︿田口問日可

M

D m 門U田 町 H可

日 ロ 同之内河口﹂﹁{問︿

MA MA

p X

←6 1 ﹂F

-DA

口 出

o

c コ

-口口

-口 Im

B a s s oコO o o So 口 一 z ao曲号ロコ曲コ且↓ Eコ唱曲芯コ・{吋同} ・

明 白mF40

o

Cコ

cl

N UMBER-REFLECTION C OEFFICIENT R NUMBER-REFLECTION COEFFICIENT RN N

日 ロ

E NERGY-REFLECTION C OEFFICIENT R ENERGY-REFLECTION COEFFICIENT RE E

ES

-o

1-

ID

NJ ID

n

rn

3:

X -a

o

0

i i i n ni| —i—r-rr i n

. --

1 I/

a

ZMat

o m m os j o

0

ロ白

+ m円 UV由 門 凶 Z

M

mzm 河 口 ベ { 問 ︿

口同戸口

o m 門U 由 mx 可

r ;: =. ;

o

Cコ

a z

2

y

5-

T~

«:

T *

/ '

7

1

/+ a

-DA

日 ロ ， 山

一口問

: : z. . ;

o a/

/

o I

i

o /

/+

+

+

/

: -: .

h

•i-

0

•y

0 0 V +

;

I

ILI

コ

C

コ

C

o

;

f -

コ

N UMBER-REFLECTION C GEFFICIENT R„ R. NUMBER-REFLECTION COEFFICIENT

I ' I K *

; 亡 コ 白

u r e(°C) ・ (C ) Tempe日 t Temperature 600

、 ' ‘ ー Hill 、 . H

、 ト 苅

400

、、、、毛ご-Katsuta K a t s u t aet e tal. a l

H H

1 0 . ) '

0D = . eKp[-22.3(kJ/mol)/RT) =4.0 4 . 0xx10•• 1 0・叫ト 22山 I ) / R T )

1 0 .g

、.、~_

Yamanishi

、¥ H

l!

陶

A u

Maksumov and ^*- Petushkov T 宇、

1 .4

川崎

1 .0

2u

1 0 .11

e . ，

町 制

Chandler and \ V\ Walter \ \ \ H \ *w-;— Zakhafov et al. \ \ \ H

u m m n r、 ? 、

\

い い い 討 が

、 、

Fuf

\

mt.

O ¥O ν ¥

A~

~E

n a v ρv o mkT us s K M

¥斗一九一¥、

H

O o Frauenfelder F r a u e n l e l d e r

。 ¥o 、 ， -. A

︼m (ENE) ﹄E --口

D

、 、 、 、 、 a 、 、 、 、 d F He 、 、 卸 m 、、 ''ao 、 h 町H 陥 、 、 unHa 、 マ L 、 、 、 、、 ⋮山 H J J 、 、

、、

Jones and • ^ Gibson

V-\ \ ^

白 、

A flyabchikov - ¥ a A y a b c h i k o v

+、、 ¥Caskey

ふ

、 、 入 、 、 、

ト ぃo

h i いr

fmNE)主主主=乙

Tanabeet e tal. a l Tanabe O 0

¥¥

1 0咽

/

t .

¥

J

D ~= 4 4.1 x1 t0 o" e*p(-75(kJ/mol)/FtTJ o . 1x 'e Kp(-75(kJlmal)IRTI¥

。

a 1 . 6

1 .8

0 . 4

1 0 ' I K 10VK A r r h e n i u sp l o r0 h emeasur~menls h ed i f f u s i v i r y0 Arrhenius plot of/t the measurements 0 of1t the diffusiviry of1 h y d r o g e ni s o l o p e si nm olybdenum hydrogen isotopes in molybdenum

0 . 6 10'/K l O ' I K

日目

Arrhenius plot ofJv various measurements of1h hydrogen A r r h e n i u sp l o ro a r i o u sm e a s u r e m e n t s0 y d r o g e n diffusiviry in tungsten d i f f u s i v i r yi nl u n g s t e n

F i g .1 1 .H ydrogenD i f f u s i o nC o e f f i c i e n ti nMo ndW . [ 7 4 ] Fig. 11. Hydrogen Diffusion Coefficient in Mo a and W.[74)

empcralυ10・ (C ) 11 e/nporalu/G (°C)

f一寸ー÷ド-.-一一一 1000

500 500

300 300

3 . 3XX11 ' e x p ( 3 7日( k J / m o l ) 1 円T ) SS==3.3 00 exp|-37.0(kJ/mol)/RT] 3

一一， 手一ーヤ H i l l

1

1 0 'ト

、¥

岸 一

1¥ O

Yamanishi

叫

上 ¥ ¥

~、\← Kat叫a

。 「 ¥¥ E 卜 、 ¥ l

主

、 、

2言

云

100~.

O ates 、 Oales \ a nd一品 and—«

E

、 、

、

と

、

1 0 . '

1 .5

1 .0

1 0 ' l K A rrheniusp l O I0 h es O [ k b i l i r y0 ydrogeni s o l o p e si l l Arrhenius plot of/r the solubility of/h hydrogen isotopes in T l OUSmv esllgolors m olybdenumb y叩various molybdenum by investigators.

10'

.0 3

11Jj1JO

andー 令 、 Gibson¥

0. 5

\o

E

、 、 Jones 、 ¥

十 c l e l l a r -M McLellan

A A Mazaov Mazacvet e tat. a l

O

¥

¥

、

守

、

o ¥

. \. d o

u . " '

、 、、

E 「¥ ¥ e 、'. 4 2

M

f

;:;0¥て e la l

oo F Frauenlolder r e l u c n r e l d c r

2 S = 2.7 X 1 0

?

¥¥i ¥ 4 ∞川 川

exp[-200{kJ/mol)/nr]

oJ=27X102exP14 ( k

0. 4

Arrhenius plot of various measurements of hydrogen A r巾 r h 加 e e 白 山 叩 山 1 1 1 solubility in f tungsten 臼 0 1 印 u剖 bi f i 町 η r y川 I η 印u n肝 gs t e 印n 5 E

F Fig. i g .1 12. 2 .H Hydrogen ydrogenS Solubility o J u b i l i t yi in nMo Mo a and ndW W.[74] .[74]

) Chロngesof 0 1Reemission, Reemission.Recycling Recycling & & .R ete時 on (( da ) Changes Retention

コ

& .T ime wi¥h Flux Flux &. with Time

j

tbJ Retention ( b )Changes Chロnges of 0 1Recycling Recycling & &R e¥e山 on w i tt hh Temperature Time wi Temperoture & &T ime

仁二

innD,S,Kr,一 -No No changes ch ロngesi 0 . 5 .K r . .•• ぃ

- Irreversible Irreversible changes chongesin i nD,S,Kr. D.5.Kr J . ( t l = J (∞) J (¥ l \J'(t)=JW-J(t)

l

~l_ トイ!

竺ー一 一 田

r f i i :

; ど こ 21

01

5 出 1 /

ト ー /

21

一一一~""

/

¥

ー…

i

¥

、 ¥

ヘ

/二;よy;L 二二 戸戸戸 L ~ぷ二三戸 二 戸 ;二ニ戸;二ニ;二ム

u . . 一 一 一 一 』 一 一 目 一 一 一 一 一一

TIME

TIME T I M Eー -→ ^

(a) Changes of reemission, recycling and retention with flux and ( a )C hanges0 1r e e m i s s i o n .r e c y c l i n ga ndr e t e n l i o nw i t hf l u xa nd t i m e . S o l i di l 岡崎 a r el o rn oc hangesi np r o c e s s e s0 1d 削u s i o r . time.Solid lines are for no changes in processes of diffusior,

( b )C hange: ， 0 1r e e m i s s i o n， r e c y c l i n ga ndr e t e n f 旧 n削with f h (b) Change-, of reemission, recycling and retention 胞 m p e r a t u r e割and 、d ti me temperature time

s o l u t i o n a nd r e c o m b i n a t 旧 na ndd o l l e dl i n e sw i l hc hanges solution and recombination and dotted lines with changes. F i g .1 3 .S c h e m a t i c s0 1r e e m i s s i o nb eha 叫o r[ 8 5 J fig. 13. Schematics of reemission behavior [85]

﹁明内宮

2SkeVD* 0 +→ Mo 25keV

9 2 d o i ;m O ι . O x 1d

6 . 5) ( 1

ω23ω-oε

2 1

ム内

1 3 ) (1 0 1 . 1( )1 d2

J441 O F ¥ Uト︿NLZOH↑乱立omU口

四 ﹁

673K 673K

]23K Implantation 373

473

573

673

773

873

TEMPERATURE/K Fig. 14. Thermal desorption of deuterium from Mo carried out immediately atfter the implantation[78]

一日ー一一一L~ ザ~~同

"^":V" " ^ I J ^ h ^ S l ' i ™ ' t♂ ~':'.j~ 局.~\-:!;:!~ι"

守

い~.~

0

( bl : (b )A Aド KE8 E R.- : :•'

F l g1 5 .C omparison0 1h i g hh e a tl o a dt e s t0 1s i n g h :し 勺. i t d l i l l 1 80 1E B. Mo Fig 15. Comparison of high heat load test of single crystalline of EB Mo 口r gedE B-Mo(AF-Mo)andp owder1 ¥ 1 ぱ ，1 ( l l l， ; ， {d o¥PM.Moi[(.， ， ; as1 as forged EB-Mo(AF-Mo)and powder inet.iNugi.'. •! M Mo(PM-Moi[Ci

¥ J )S u r f a c ea f t e rN BItest t e s t ta) Surface after NBI

f

f

(o)SCEB-Mo (a! SCEB -Mo

(b)AFEB-Mo b) AFEB - M o

(C)PM-Mo ic ] PM -Mo

( b )C rosss e c t i o n0 1t h eR FPl i m i t e r (b) Cross section of the RFP limiter

Dependence Dependenceof o fVloop Vloopon onPlasma Plasmacurrent. c u r r e n t

G r a p h i t eand andMolybdenum. Molybdenum Comparisonof o fSUS, SUS，Graphite Comparison TPE-1RM15 TPE1RM15 向

L _ _. .! ] I

← ， _i

. IJ .. . )J ._!_

iL l L I

!

-I— I

I

J

1111101111ft'IL1triti--

【

n

L _ I I1 l__l.

:

﹄

nr U . l ii1 I'ii

日

J .. I

)11'-

"

; i l r J A ♂

40

u

ran

ny

P

=5

^k"

，，1 1

fWBx

n|;

M*

りrド

aoo一﹀

'

& in*,

ea メ 7,

s us SUS

口 raphite D G Graphite

l臼

十 +

,

" (•t —t ft

， [1

i

M olybd巴num Molybdenum

l' ¥-

i••• i - i

¥

~;IIS

C1 ' 1 1 1 '1 )1 1 l1 "1 J U? u " " r p9 日 2 í)~l !l pun u? 1iu^,rp 3B I-T'''1 ， ， 一

;;IIS c it i I'ui "r-r ¥-:---¥寸寸 r inut) 寸

I i -7—r- i - | — i ~.J I1 l l 1川 lit) IBM

- —i—i

i

r

¥ !r ') •， ''

r

i

t

J

1

t

I p( k A ) lp (kA) F ig.1 6. Fig. 16.

L oopv o l t a g ev sp ¥asmac u r r e n t' "R FP(TPE.1RM15) l o r Loop voltage vs plasma current in RFP(TPE-1RM15) for

different limiter material of graphite, stainless steel and d i f f e r e n tl i m i t e rm a t e r i a lo fg r a p h i t c .s t a i n l e s ss t e e la nd m olybderr u r n [ 7 3 } molybdenurn(73J.

I

T~

・ 己L'HFl 1 1向 ? " 円

lmlter TPE-1RM15 with Moo m movable limiter T PE・1RM15 w lth M ovable I

L Limiter imiter p po os si it t ii oo nn = 8mm 8mm

0.05

0 1 1E m i s s i o n ( A r b i t ) Oil Emission(Arbit) 0.00

J

i i i i | i ^ * 1 " i | i i i i "| I i l ' i |

i i i i | i i T r p n

i i |

0.25

^t¥f, • •,Radiation(Arbit) rrrrfT.'"'?,,,,, y ^ r ^

自由自

0.05

Da(Arbit)

e . e e

I I I I I I I i I I I I I I i I i i i i i i I i i i i I T i i i

i '''' I

0.05

J

MoJE m i s s i o n ( A r b l t ) Mol Emission(Arbit) 0 B. . e0 e9•

if

i i i i | i i i i | i i i 11 i i rn p i i i i | 11 i rrrrr r ' p i i i 下i 1 |

3 000• 3000

/一一「¥ー

2 000 2000

r

1 10 00 00 0-

i

'

i

i

|

i

i

i

i

|

i

i

i

S urface T emp.(OC) Surface Temp.(°C)

i

|

i

i

i

I

|

i

I

i

i

)

I

ー I i 「寸寸一 ~ r - γ

「寸"

200 —

I l aPlasma (kA) 4P s m a Current c … 州 i i i i | ;• i i | i i i i I i i i i | i i i i I i I -2.5

0 3. . 80

2 2 .. S5

5 7 5. . 80 7. . 55 t . i n e 1 m ， ) tine 6is)

1 10 0. . 90

一1 "寸 寸

1r p ~ r - r r - | 12.S

IS.8

F i g .1 7 .C hanges0 lasmap a r a m e t e r s0 FP(TPE-1RM15) Fig. 17. Changes of1p plasma parameters of1R RFP(TPE-1RM15) w i t h Mo i m i t e r .I no r d e rt og i v ev e r yh i g hh e a tl o a d with Mo l limiter. In order to give very high heat load 剖 d eepI n l oI h ep l a s m a . [ 7 3 ] t h el i m i l e rw asi n s e r t the limiter was inserted deep into the plasma.[73]

・

・ ・ ・ ・ ・ ・・

Table 1,， T abl 1

n n ,，

n n ,，/ /n n. ,

n n .， 1

1 (刷)I p ) g c o n f i a u r . P .， .， (( I1 t1 ) I g a• ssI I p pCIA) conliBur.

4 . D 4.0

20(B) 加

回 t e r i a l IT rs! T:l.f lootthheerr c co on nd di it ti io on ns s •aterial T TL . CC M a nn dd r re em ma ar rk ks s ---一 γ ーー-~ . e .'ev) 、 明) 1 ( ， ， ) (ev) a

品川祖 1 hl lil/div n i¥ l¥ l l i.. o iv l lia orτ div

ω I ，I v 1

1 jmo 問 T i C。 Ho TiC/Io

1.0

1.5

11-1401)

H,

i i v

TiC/lto

11 2 12

4.7

0.3

OH

He

1 i m

Ti

3

0 . 3 0.3

，

1

1 2 12

Fe: 0.9 9 ¥ 4.1 u Ft:

1.8 B

Fe:

0.1 4¥

Fe:

0.55 1 1 1.5 5

I

•o: 了 93寸 650 戸 品。

，

Hi: 町

0.03 0 . 0 3

A DEEXX AS SD

:S S SS

A SDDEE AS XX

SS

. ASD A S D EF XX

'

B B

SS

ASDEX ASDEX

•

B

4.7 4 1

OH 1 D D, 11 i; m"-¥ T Ti 1 0.3 0 . 3 1 OH . 1'1

SS

ASDEX

3 1 3

0.3 OH... 11 i m in 1 T Ti Di. 1 1 10 . 3 1O H..1 D

SS

ASDEX

I

0.2 OH I D D. , I0 . 2 I OH

¥

7.0 7 0

I0 . 2 0.2

1 .9 1.9

I0 . 0 6 I 0.06

1 . 1.99

r El fer~nces references

J ; TT-66 O0

SS

0.3 I0 . 3

Idl~1

い

TI i T

d i v

0.22 I OH OH I D D, .

い ! い ! 1I im tn

Mo S S5 Mo :S

1i im m

Mo Mo

・

holloi Te(r) h o l l oT e (r J

SS 山

I0 . 4 I OH H 0.4 OH I H,. 111m W : SS SS 1 i m lW

I3 3 I3 3

h o l l o wT e ( r )? hollow Te(r) ?

IOH e I1 1 f t 側 ! L I N C . OH IH He INC. 1i im m 1 UC0HEL I0 H ID 印 刷' E L J N C OH D,. IJ 1J Im E I IttCONH, wc.

・

・

( A )T .S uqie e ta 1.，K aku)'uqo-K nkyu 6 5( Supp1 .J( 1991) 2 87，i n Japanese. J.p.ne.... (A) T. Susie et al,, Kakuyuso-Kenkyu 65 (Suppl.) (1991) 287, in u..mann et t. 1 . ， J .N ucl .M .ter，1 45-147 ( 1987) 96. 96. ( B )c (B) 0.，F Fussmann al., J. Nucl. Hater. 145-147 (1987) ( C) B . Li lJ ~chultz e td 1 . }J .N ucl .M ater 1 28 & 29 ( 1984) 555. 555 (C) B. Lipachultz et al., J. Nucl. Mater. 128 & 1 129 (1984) . ， N ucl. F U5ion 18 1 包 ( 19'8) 1305. 1305. ( D }E .H innov et et al., al (D) E. Hinnov Nucl. Fuaion (1978) ( E )K . . h r i n q . . r. . t. 1 . ， J uc1 .M .ter. 1 62-164 ( 1989) 398. 398 (E) K. B Behrinjer et al., J.，N Nucl. Mater. 162-164 (1989) 目

目

A A

'

TiC/lo

3 3

OH I H He I OH e

ref

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R ecent I s s u e so IFSS e r i e s Recent Issues offN NIFS Series N IFS・101 NIFS-101

H .M omota.A .I s h i d a，Y .K o h z a k i .G .H .M i l e y .S .O h l .M .O h n i s h i H. Momota. A. Ishida, Y. Kohzaki. G. H. Miley. S. Ohi. M. Ohnishi o m i t aa ndM .T uszewski K .Y oshikawa.K .S a t o .L .C .S t e i n h a u e r，Y K. Yoshikawa. K. Sato, L. C. Steinhauer, Y.、T Tomita and M. Tuszewski C ρ /I( " ( ' I ' t l l l l lD l ' Si g l lo ). . ' I I ' ，FRC 山w tor" . ¥ R 1ι 切I S "; u l y Conceptual Design of(f D^llc hRC R Realtor "ARTEMIS" ; J July 1991

N I FS-l02 NIFS-102

N .N akajimaa ndM .O kamoto.R " t l l t i o/lsυ 8f 1l lI O/ls" ' 1 < / 1 1 1 1 1 川n / H ' S N. Nakajima and M. Okamoto. Rotations of(Bulk Ions and Impurities ; 1 1N OII-AxisymmetrIc T o r o u J a lS y s lt ' ms; u l y1 991 in Non-Axisymmetric Toroidal Systems ; J July 1991

.J .L ichtenberg，K .t I o h .S .1 I oha ndA .F ukuyama，T h ( 'R υ 1 ( '， ， / N IFS-l03 A NIFS-103 A. J. Lichtenberg, K. Itoh. S. -. I. t Itoh and A. Fukuyama, The Role of S to l ' l l l l s t i c i t ¥ 'i awtoolhO s d l l l l l i 川，; ug. 1 9 9 1 Stocltasticity innS Sawtooth Oscillation :A Aug. 1991 N IFS-l04 NIFS-104

K .Y amazakia ndT .A mano，P I I I S I I I< I1 i"，川中川 1S i m l l l a r i o l ll v l 山I d i l l g K. Yamazaki andT. Amano, Plasma Transport Simulation Modeling j ;>rI h l i c a lC 川 ザ 1I1( > I H t . ' n tSystems: 仇S t ( ' I I I S :A ug. 1 9 9 1 for Helical Confinement Aug. 1991

N IFS-l05 NIFS-105

.H ayashi，K .W atanabe.R .H o r i u c h . iM .T anaka，N .S a w a i r i T .S alo，T T. Sato, T. Hayashi. K. Watanabe. R. Horiuchi. M. Tanaka. N. Sawairi a ndK .K usano，R ρh '" ， "C ρmprl ' s s i h i l i t yυ 1Dr I ¥ '' ll I M'l，~H('t;( and K. Kusano. Role of Compressibility on Driven Magnetic R ( ' (υI l I U ' C l l川 i: A ug. 1 991 Recotittection Aug. 1991 目

N I FS-106 NIFS-106

Q ianW eni a，D uanY un0‘W angR ong. onga ndH .Narumi. Narum . i Qian Wen -J Jia, Duan Yun -8 Bo, Wang Rong •L Long and H. E I ( ' c t m l lI mpuct， . E utati 川 lo υs i t i r ( '1 0/lsa r t i a [時 ' l J¥ ' l J Electron Impact Excitation of{P Positive Ions •P Partial Wave υI/[omh. : ik川 w[" 1 ' 1 '1 υ日 m l l l lυ 1 1; e p .1 991 A ppmudli l C Approach inl Coulomb •l Eikonul Approximation ;S Sep. 1991

，， 1 <

N IFS-l07 S .M urakamia ndT .5 alo， M 山 ，内 山 " I'Particle Pu l 1i ' S i l l l l l l l l l i O I 1I う f NIFS-107 S. Murakami and T. Sato, Macroscale Simulation of E X l e r n a l l 1 'D r i r e l lM a g l l ( ' t i cR . ， (υI I I I ( ' C l i o l l :S ep. 1 991 Externally Driven Magnetic Reconneclion: Sep. 1991 N IFS・108 NIFS-108

Y .O gawa，T .A mano，N .N akajima，Y .O hyabu K .Y amazak . i Y. Ogawa, T. Amano. N. Nakajima, Y. Ohyabu. K. Yamazaki, S .P .H irshman，W .. 1 anR i ja ndK .C .S haing，Neodassi("ul S. P. Hirshman, W. I. v van Rij and K. C. Shaing,/Veoclassical I 'o r lA l l a l y s i s; 1 1I h ( 'B U l l a l l aR . ' g i l n eυ 1 1L urg. ，l Ie l i c a lDe l ' Ice T ra/ls Transport Analysis in the Banana Regime on Large Helical Device ( L lID)w ; l hl / r eD KESC ep. 1 991 tLHDI with the DKES Cυod *e: ;S Sep. 1991

N FS-l09 NI IFS-109

Y .K ondoh、 T h o l l g h lA l l a l y s i sυ nRda . r a l i υI1l 1ndG ( '/le r a lP rindple1 0 Y. Kondoh, Thought Analysis on Relaxation and General Principle to F indR el αtedS la/e;S ep. 1 9 9 1 Find Relaxed State: Sep. 1991

N IFS-ll0 NIFS-110

.I d a，H .I g u c h i，K .H a n a t a n iS .M o r i l a，O .K aneko， H .Y amada，K H. Yamada. K. Ida, H. Iguchi, K. Hanatani, S. Morita, O. Kaneko, H .C .H owe，S .P .H irshman，D .K .L ee，H .A r i m o l o，M .H osokawa， H. C. Howe, S. P. Hirshman, D. K. Lee, H. Arimoto, M. Hosokawa. H .I d e i，S .K ubo，K .M alsuoka.K .N i s h i m u r a，S .O kamura， H. Idei, S. Kubo, K. Matsuoka. K. Nishimura, S. Okamura. Y .T a k e i r i，Y .T a k i l aa ndC .T akahashi，S h < ( { m l l(l¥・ S h i f li 川 Y. Takeiri, Y. Takita andC. Takahashi, Shaftanov Shift in/l L LowAspect-Ratio lleliotron '• 1 TorsatronCHS ;S Sep 1991 A s p ( 'C1R u l i ρl Ie l ; ' 11 Iυ1 υr S ( l / m /lC lIS; ep 1 991

守

守

， 1

N IFS-lll NIFS-111

i，M .U chidaa ndT .S a l o，S i l 1 l l /[ a l ; 山 ISW めィゲ t e { l ¥ t川 U R .H o r i凶 h R. Horiuchi, M. Uchida and T. Sato, Simulation Study of S Stepwise R daxatu川 1 phel"OlIwkP I I I S I I I I I: O C l .1 9 9 1 Relaxation in/1“ aS Spheromuk Plasma .Oct. 1991

N IFS-112 NIFS-112

M .S a s a o .Y .O kabe.A .F u j i s a w a .h .I g u c h i .J .F u j i t a，H .Y amaoka M. Sasao. Y. Okabe. A. Fujisawa. h. Iguchi, J. Fujita, H. Yamaoka a ndM .W ada.I hTl'/iJp ' 山 ' 1 ] (r Vcgaf/rcI I l'U¥T / 0 1 1S !' f f f T C Sf Ol and M. Wada. Development of{， Xegativc Heavy Ion Sources for P I I I . ¥Hl l lP υ! e l l ( ; t 11. ¥ 1C f l s / { r CIIll'/ll ; c t .1 991 Plasma Potential Measurement ;O Oct. 1991

N IFS.113 NIFS-113

S awalaa ndH .N akashima，T r i t i u mC O l l l e1 lt o e l l e tin i 1 l S..K Kawata and H. Nakashima, Tritium Content offa a DT DT P Pellet l 1 Ie r t i a lC 0 1 l f i n e m e l l lF u s i o n; t . 1991 1 9 9 1 Inertial Confinement Fusion ; Oc Oct.

N IFS.114 NIFS-114

M .O M. Okamoto, k amoto，N N. .N Nakajima a k a j i m aa and ndH H. .S Sugama, ugama，P Plasma lasmaP Parameter arameter E s t i m a t u J I I sf o rt h eLar~.' e l i c a lD nice8 ased0 1 1t h eG y r o . Estimations for the Large H Helical Device Based on the GyroυhmS c a l i l l g; O c ¥ .1 9 9 1 R e d l l c e d8 Reduced Bohm Scaling Oct. 1991 守

N IFS.115 NIFS-115

Yα 坦b e，S t l l d yゲ ， { I I -P r o d l l c t i m /i l la l a s m a . S p u t t e r7 j ' p e Y. Okabe, Study of A An' Production in aP Plasma Sputter Type el o nS ρI I r c e; t . 1991 1 9 9 1 N e g a t i' Negative Ion Source ; Oc Oct.

N IFS・116 NIFS-116

M .S a kamoto，K .N .S a l o，Y .O gawa，K .K awahala，S .H i r o k u r a， M. Sakamoto, K. N. Sato, Y. Ogawa, K. Kawahata, S. Hirokura, S ka j i m a，K .A d a t i ，Y .H amada，S idekuma，K .I d a，Y .K awasumi， S..O Oka/ima, K. Adati, Y. Hamada. S..H Hidekuma, K. Ida, Y. Kavrasumi, M .K o j i m a，K .M asai，S o r i t a，H .T akahash . iY .T a n i g u c h i，K .T o ia nd M. Kojima, K. Masai, S..M Morita, H. Takahashi, Y. Taniguchi. K. Toi and T .T s u z u k i， F a s tCoolill~ h ef/o l / l刊 l aw i l h/ ceP e l l e t1 1 1 ; 出 t umm T. Tsuzuki, Fast Cooling P Phenomena with Ice Pellet Injection in t h eJ the JIPP T-IIU Tokamak; Oct. 1991 l PPT I I UT o k a l l l a k ;O c l .1 9 9 1

N IFS.117 NIFS-117

，

I oh，H .S a n u k ia ndS . 1t I oh，F a s tI m lL o ' 'a ndR a d i a lE h ' c t r i c K .t K. Itoh, H. Sanuki and S... -I. Itoh, Fast Ion Loss and Radial Electric e l l d e l s t e i nV I I A S t c 'l I a r a r o r ;O c. t1 9 9 1 F i e l d川 Field in W Wendelstein Vll-XStellarator; Oct. 1991

N IFS-llB NIFS-118

田 k a，K C ' f 1 le lO p r i l l l l l l l lN "C lr l y 一山 w l y l i c a l Y .K ondoha ndY .H o Y. Kondoh and Y. Hosaka, Kernel Optimum Nearly-analytical Discretization (KOND) Method Applied tooP Parabolic Equations 1 l( KONDJM elhod1 ¥ l ' l 'l i e dt a r a h o l i cE q r w t i 川町 D i s c r e t i : a t i o < >:N o v .1 9 9 1 «KOND-P Scheme»: Nov. 1991

¥ I ' o -a n c lT l l I w D i m e l l s i υI la lS i l l l l l l a l i υn N IFS-119 T .Y abea ndT .I s h i k a w a，T NIFS-119 T. Yabe and T. Ishikawa, Twoand Three-Dimensional Simulation

C o c l ef o rR a c l i a l i o1 lHydmdY1 la m i c si 1 lI C f ;N o v .1 9 9 1 Code for Radiation-Hydrodynamics in ICF; Nov. 1991 N IFS-120 NIFS-120

“

S awata，M .S h i r o m o l oa ndT .T eramoto，D ellSi r y C c l f l y i 1 lgp ，r t i d e S..K Kawata, M. Shiromoto and T. Teramoto. Density-Carrying Particle

M "l Method for Fluid ;N Nov. 1991 ! to d j i >rF l u i d ; o v .1 9 9 1 N IFS-121 NIFS-121

T .I s h i k a w a，P .Y .W ang，K .W akuia ndT .Y abe，A e t l w c lj i u 'the l h e T. Ishikawa, P. Y. Wang, K. Wakui and T. Yabe, AM Method for H i g h s p e e c lG e n e r a t i Oll " ( / I ldomN l I l I l hl'fsw i l hA r h i l r a r y High-speed Generation oflR Random Numbers with Arbitrary Distributions; Nov. 1991 ov. 1 991 D i s t r i h l l l i o l l s ;N

N IFS-122 NIFS-122

K .Y amazaki，H .K aneko， Y .T a n i g u c h . iO .M o l o j i m aa ndL HDD e s i g n K. Yamazaki, H. Kaneko, Y. Taniguchi, O. Motojima and LHD Design G r o l l P，S l a l l l so HDC O l l l r o lS 口t 仰 D 自 i g1 l:D 自 1 9 9 1 Group. Status offL LHD Control System Design : Dec. 1991

，

NIFS-123 Y. Kondoh. Relaxed Stale of Energy in Incompressible Fluid N IFS-123 Y .K ondoh，R e l a x e dS l l Il eィ 1E 1 I . . ， . gyi l l1 mυI I l p r e s 川h l eF l l l i c land ( / l Id 川 n p r e s s i h l eMHD l l Ii d ; e c .1 9 9 1 1 m Incompressible MHD F Fluid ;D Dec. 1991 N IFS-124 NIFS-124

K .I d a，S idekuma，M .K o j i m a，Y .M iu悶 ， S s u j i，K .H o s h i n o .M. M‘ K. Ida, S..H Hidekuma, M. Kojima, Y. Miura, S..T Tsuji, K. Hoshino. M o r i .N .S u z u k i，T .Y amauchia ndJ FT-2MG roup，E dgeP o i o i d a l Mori, N. Suzuki, T. Yamauchi and JFT-2M Group, Edge Poloidal R o t a l i m lP r c Rotation Profiles of1H H-Mode Plasmas in the Tokamak l ! i l e :1 -ModeP I ωl I l a si l ll h eJFT-2M JF1 ~2M ' l ikamak:; D e c .1 9 9 1 Dec. 1991

、

N IFS-125 NIFS-125

，

H .S ugamaa ndM .W akatani， S t a l i s r i c a lA I l C l/ y s i s1 1AAnomalous 1 Iυ l I l a l O l l S H. Sugama and M. Wakatani, Statistical Analysis of

T r alJs p o r ti nR e s i s t i v eI n t e r ( ' h a n g eT l l r h u l e J l( ' e: D e c .1 9 9 1 Transport in Resistive interchange Turbulence ,-Dec. 1991

NIFS-126 N IFS.126

K. Narihara, AS Steady r e a d yS State r a r eT Tokamak okamakO Operation peraru J / Ih by yU Use s ' ，0 of1M Magnetic agneru K .N a r i h a r a，A M υn o p o l 町; ec， 1991 1 9 9 1 Monopoles ;D Dec.

N IFS.127 NIFS-127

K K.，I t Itoh, oh，S S.，. -I. 1 .I Itoh t o ha and ndA A.，F Fukuyama. ukuyama，E Energy l l e r g yT Transport r a l l s pρ r ri in l lr the h eS Steady r e a d y S r a r eP lasmaS u s r a i l l e db e l i c i l yC I /r r e n lD r il'e; J a n， 1 992 State Plasma Sustained byyDC DC H Helicily Current Drive ;Jan. 1992

amada，y awasumi，K a s a i .H g u c h i，A .F u j i s a w a，J IPPTT . N IFS.128 y NIFS-128 Y.，H Hamada, Y.，K Kawasumr, K.，M Masai. H.，I Iguchi, A. Fujisawa. JIPP

IIU Group and Y.，A Abe, New Hight Voltage Parallel Plate Analyzer ; I I UG roupa ndV be，N ewH i / ih lV o l l a g eP a r a l l e lP l a l eA / la l y :e r; Jan. 1992 J an， 1 992 N IFS.129 NIFS-129

，

a t o， L ine-Emi日 i o nC r o s sS e c t i υIISl o rI h eC h a r g e・ K d aa ndT K..l Ida and T.，K Kato, Line-Emission Cross Sections for the Charge-

R ea l ' l i o nb e 削 ' e e nF u l l yS t r i p p e dC a r h o l la l l dA lomic Reaction between Fully Stripped Carbon and Atomic H ydrogeni n7 i οkamakP I αs m a ;J an， 1 992 Hydrogen in Tokamak Plasma; Jan. 1992

e~杭'hallge exchange

N IFS・130 T a y a s h i，A .T a k e ia ndT a t o，M a g l l e l i ( 'SW 向 ，( ' eB r e a k i n gi n3 NIFS-130 T.，H Hayashi, A. Takei and T.，S Sato, Magnetic Surface Breaking in 3DD MHD q u i l i b r i a0 1 = 2H e l i o l r o/l ;;J an， 1 992 MHD E Equilibria of1 1=2 Heliotron Jan. 1992 N IFS.13 1 NIFS-1 31

.I c h i g u c h ia nd5 1 .I t o h，B e l aL i m i l0 e s i sl I¥ ' eP l asma K .I t o h，K K. Itoh, K. Ichiguchi and S.，. -I. Itoh, Beta Limit of1R Resistive Plasma / Jr s a t r o I 1 IHe ! i o t r o/l;; F e b .1 992 in11長 TorsatronlHeliolron Feb. 1992

N IF5.132 NIFS-132

K .S a t oa ndF iyawaki，F O f ' m a t i o l /( ゲ ーP ，，'sheatha l l dC urre/JI. F r e e K. Sato and F.，M Miyawaki, Formation of Presheath and Current-Free D oubleL a y e ri / la wo.EI 自 r l'Ol l . T e m p e r a l l l r eP lasma; eb， 1 992 Double Layer in aT Two-Electron-Temperature Plasma ;F Feb. 1992

N IF5.133 NIFS-133

aruyamaa nd5 awata，S l I p e r p υs e d L “ 日rE l e ( ' / m l lA C ('el e r a l i o l l T T.，M Maruyama and S.，K Kawata, Superposed-Laser Electron Acceleration F eb， 1 992 Feb. 1992

N IF5.134 NIFS-134

V i u r a，F kano，N u z u k i，M o r i，， . t oshino，H Maeda Y.，M Miura, F.，O Okano, N.，5 Suzuki, M.，M Mori, /.. H Hoshino. H.，Maeda, T akizuka，J FT.2MG roup，5 . '. 1I t o ha ndK t o h，R apiJC h a l l g eof o } T.，T Takizuka, JFT-2M Group, S.-l. Itoh and K.，I Itoh, Rapid Change 守

H y J r o g e l lN 町山a lE l l e r g yD i s r r i h l l l i 川 Ia I I . T r a l l s i r i o l li l lJFTJ l T Hydrogen Neutral Energy Distribution atrU LIU-Transition in 2M 1 1 1 1 υJe; e b .1 992 2M 1 H-mode ;F Feb. 1992 N IFS・135 NIFS-135

H i，H oyama，A u j i s a w a，5 h i n o h a r aa ndK Miyamoto H.，J Ji, H.，T Toyama, A.，F Fujisawa, S.，5 Shinohara and K.，Miyamoto F Fluctuation I r "川 a l i o l la and l l JE Edge JgeC Current l l r r e l l rS Sustainmenl u s l a i l l m e l l li in na R Reversed-Fielde ¥ ' e r s e J . F i e l d . eb， 1 992 P i l l c h ;F Pinch; Feb. 1992

NIFS-136 N IF5・136

K K. .S Sato a l oa and ndf F.，M Miyawaki, iyawaki， l Heat Ie a rF Flow l o"， ( of > fa aT Two-Electron-Temperulure " ，o E l e c/r(J/1. T e m p e r a l l l r e Plasma through lhe Sheath in the Presence offE Electron Emission: hj J lt h l 'P r e s e n c eo l e c t . ， O I lE m i s s i ο 1 1 : P lasmat h m l l l l h! h eS hαt M ar， 1 992 Mar. 1992

N IFS.137 NIFS-137

T a y a s h i，U chwenna ndE 1 r u m b e r g e r，F i l ' i JL i l l eD i ¥ '' r s I l 川 T.，H Hayashi, U.，S Schwenn and E.，5 Strumberger,Field Line Diversion P 川 ' p e r ! 附イ i / li t eβ I e l i a sE ' l u i l i i J r i l l :M ar ， 1 992 Properties of F Finite fi l Helias Et/uilibria; Mar. 1992

“

' ，

，

amagish . iK i l l e t i c， 1p / lr o a cI l/ O l l gW a ¥ ' eL 刊I g t hM υd e sin i l l N IF5.138 T NIFS-138 T.，V Yamagishi, Kinetic Approach to0L Long Wave Length Modes R o t a t i n gP l a s m a s ; Ma r .1 992 Rotating Plasmas; Mar. 1992 N IFS.139 NIFS-139

K .W atanabe，N akajima，M kamoto，V akamuraa ndM K. Watanabe, N.，N Nakajima, M.，O Okamoto, Y.，N Nakamura and M.

Wakatanl，Three-dimensional r h r ( ' ( ' d i t 1 /刊 日 川 w lMUD ， " 4 I 1 f ) Equilibrium / : . c / u i l i h. ，i un1 in i nthe I I / ( 'Presence P"IJ.~ ('I/( ( ' I~/ Wakatani, of

B ( / 川 . H r l l pC urre n!fur f υ， .Large L"， . g ， < Helical I I ( ， / i ( ' ( l /Device /)('I'U'('iLIID); I U / / ) I :Mar Mar 1992 1992 Bootstrap Current NIFS.140 NIFS-140

NIFS.141 NIFS-141

、r

K .Itoh. 1 1 0 h，S. 5，. 1 1 0 hand andA. A .Fukuyama. Fukuyama，Theory l' h ，' O I oj υ Anomalous . . ¥ J / (I m a l l l l l s} I " lw . ¥ p ( I r l K. -1I.. Itoh Transport i l / Toroidal lim'idal " < ' Ii c < l1 P l a s l I l < l s :Mar. Mar， 1992 1992 in Helical Plasmas; Kondoh，Internal 1 1 1 1 "/'11