Calendars

Comparison of the beryllium films prepared by thermionic vacuum arc and thermal evaporation methods

Description
Comparison of the beryllium films prepared by thermionic vacuum arc and thermal evaporation methods
Categories
Published
of 4
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
Share
Transcript
   Comparison of the beryllium films prepared by thermionic vacuum arc and thermal evaporation methods C. P. Lungu 1 , I. Mustata 1 , V. Zaroschi 1 , A. M. Lungu 1 , P. Chiru 1 , A. Anghel 1 , C. Porosnicu 1 , I. Jepu 1 ,V. Bailescu 2 , G. Burcea 2 , G. Dinuta 2 , . Din 2 , !. Balan 2 , G. "er#an 2 1  National Institute for Lasers, Plasma and Radiation Physics, Bucharest, Romania 2  Nuclear Fuel Plant, Pitesti, Romania 1.Introduction $he I$%&'li(e )all Pro*ect, part o+ the J%$ progra--e in support o+ I$%& 1'1/0, to #e i-ple-ente on J%$ in'clues &D acti3ities to e3elop a -etho o+ epositing Be la4ers on inconel an an interla4er plus a Be o3erla4 onto Be tiles an characteri5ation o+ the Be coating purit4  #4 sur+ace an structure anal4sis techni6ues as 7ell.$her-ionic 3acuu- arc 8$VA9 eposition process has  #een chosen in orer to o#tain high ensit4 o+ the +il-s :'110 +or the prouction o+ the ;-ar(er< tiles. $he ;-ar(er< is a Be tile 7ith a stripe o+ 2'= >- in thic(ness o+ an easil4 etecte hea34 -etal 8e.g. ), &e, !i9 eposit'e on it as an interla4er, an 7ith a +e7 -icrons 8? @': >-9 la4er o+ #ul('li(e Be on top o+ that. I+ the outer la4er is eroe at the sa-e rate as the #ul(, then the erosion rate can #e eter-ine #4 etecting the thic(ness o+ the la4er +ro- the +inal sur+ace, +or erosion o+ less than the +il- thic(ness. $o ena#le -easure-ent o+ erosion greater than :, >- there 7ill #e notches 81/ an 2/ >- eep9 on the tiles. $he -a*or e++ort in &D is to prouce high'purit4 la4ers 7ith opti-ise co-position, an to select the #est inter'la4er -aterial to ensure goo ahesion an ther-o'-e'chanical co-pati#ilit4. $he opti-isation o+ the -anu+ac'turing process 8la4er thic(ness, structure an purit49 has  #een carrie out on 3arious su#strates glass, silicon, -et'als. $he opti-ise -ar(er la4ers +or +urther testing 8in'cluing per+or-ance uner high'heat loas9 7ere eposit'e on = c- thic( Be #loc(s o+ J%$ an I$%& rele3ant 6ualit4 8" grae +ro- Brush )ell-an9. 2.Preparation methods $7o -ethos o+ Be eposition ha3e #een use to prouce test sa-ples stanar ther-al e3aporation in 3acuu- an $her-ionic Vacuu- Arc 8$VA9 techni6ue 1'20. $he lat'ter one has #een selecte to prepare @ >- thic( +il-s on the ;s-art<-ar(er tiles an the +or-er one to prouce Be +il-s on inconel tiles. ig.1 "et'up +or #er4lliu- eposition using ther-ionic 3acuu- arc -etho.  $VA is #ase on the electron #ea-'inuce e3aporation, as sho7n in the sche-atic ig.1. A tungsten hot athoe +ila-ent surroune #4 a )ehnelt c4liner is heate #4 an eEternal lo7 3oltage'high current ac suppl4. $her-o'elec'trons e-itte +ro- the tungsten +ila-ent are accelerate to7ars the anoe. Figh e3aporation rate o+ the anoe -aterial leas to high 3apor ensit4 in +ront o+ the anoe. $he space ensit4 o+ these particles is high enough to lo7er the ioni5ation -ean +ree path -a(ing it s-aller than the cathoe  anoe istance. As a result, plas-a is ignite in that region 7hile the surrouning space is e3ac'uate to #elo7 1/ '= Pa. Hner these conitions high purit4 +il-s o+ the anoe -aterial can #e reprouce 7ithout re'uction or -oi+ication.$he coatings o+ inconel tiles 7ere per+or-e using the 3acuu- ther-al e3aporation e6uip-ent o+ the !uclear ig.2 "et'up +or #er4lliu- eposition using ther-al e3apo'ration -etho in 3acuu-. uel Plant 8!P9 in Pitesti. $he sur+ace o+ the sa-ples 7as prepare #e+ore eposition #4 the stanar san  #lasting proceure use #4 the !P. $he sche-atic ar'range-ent use +or #er4lliu- eposition #4 3acuu- ther'-al e3aporation -etho is sche-aticall4 sho7n in ig. 2. $he e3aporation cruci#le 7as #er4lliu- oEie an the heating co-ponent 7as a -ol4#enu- 7ire o+ = -- i'a-eter 7oune aroun the e3aporating cruci#le. 3.Film structure I-ages in ig. = an ig.  sho7 the structure o+ #er4lli'u- la4ers eposite #4 t7o techni6ues $VA an ther-al e3aporation, respecto3ell4. %3aporate +il-s 7ere pre' pare using the +acilities at the !uclear uel actor4 in Pitesti, &o-ania. It is notice that +il-s o#taine #4 $VA are -uch s-oother than e3aporate la4ers. 'ra4 i++rac'tion stuies ha3e also pro3en highl4 orere cr4stalline structure o+ $VA'prouce +il-s. ig.= "%M i-age o+ Be +il- prepare #4 $VA -ethoig.  "%M i-age o+ Be +il- prepare #4 ther-al e3aporation -etho  During epositions, a 6uart5 cr4stal -onitor 7as use to -easure ;in situ< the thic(ness o+ the eposite la4er #4 $VA -etho. In orer to -easure thic(nesses larger than 1 K - 8the upper li-it o+ the 6uart5 sensor9 a coole hol'er 7as esigne an #uilt ha3ing in the +ront o+ the sensor 7ino7 a isc 7ith a 1/ -- ia-eter hole. An electrical -otor 7or(ing in 3acuu- ro3e the isc 7ith 1// rp-, ensuring a +actor o+ =/ #et7een the real thic(ness eposit'e on sa-ples an the thic(ness -easure #4 the thic('ness -onitor. A+ter eposition, the thic(ness o+ the la4ers 7as -easure on the 7itness sa-ples using a st4lus pro'+iler. "teps 7ere prouce #4 -as(s on the 7itness sur'+ace or #4 che-icall4 etching a ri# in the centre o+ the sa-ple. Be +il-s thic(nesses 7ere in the range o+ . K /. K -.Ato-ic orce Microscop4 8AM9 -easure-ents, in tap'ing -oe, ha3e pro3e the s-oothness o+ the eposite +il-s 7ith pea( to 3alle4 roughness in the range o+ =// ±  / n- +or Be coatings 8ig. 9. ig.  AM i-age o+ a t4pical Be coating on stainless steel. $he cr4stalline structure o+ the eposite +il-s 7as con'+ir-e #4 'ra4 Di++raction 8&D9 anal4sis. ig.  sho7s the &D pattern o+ the Be coatings on silicon 7a+er 7ith high intensit4 an sharpness o+ the Be pea(s. $he sur+ace +il- co-position anal45e using an PFI'Per(in %l-er -oel =/1 Auger spectro-eter 8inetic energ4 rangeN /'=2// eV, resolutionN /.O9 sho7e less than 12 O oE4'gen an car#on inclusion into the thin outer-ost la4er. A t4pical Auger spectrogra- is sho7n in ig.  gi3ing the , C an Be concentration. $he +eature aroun 21 eV correspons to the Ar i-plante #4 the ion gun use +or sur+ace etching prior to the Auger -easure-ent.ig.  &D pattern o+ the #e +il- coate on "i 81119ig  Auger -easure-ents o+ Be +il-.$he Be coating sa-ples 7ere eEpose to step7ise'in'crease ther-al loas +ro- . MJ-2 to 2/ MJ- 2  8/. M)- 2  to 2. M)- 2 9. $he tests 7ere one at the start'ing te-perature t4picall4 #elo7 1// QC. $he -aEi-u- sur+ace te-perature rose up to aroun // ? @// QC. $he 20 40 60 80 10020406080100    B  e   (   1   0   1   )   B  e   (   0   0   2   )   B  e   (   1   0   0   )   S   i   (   1   1   1   )     X   R   D    I  n   t  e  n  s   i   t  y ,  c  o  u  n   t  s 2 θ  te-perature istri#ution 7as +airl4 ho-ogeneous at the loae area an no local o3erheating 7as o#ser3e #4 the I&'ca-era. $he oEiation o+ the coating sur+ace 7as o#'ser3e as nano'scale sur+ace roughening o+ the platelets, sho7ing the potential +unction o+ Be la4er as an oE4gen getter. 4. Conclusions It has #een pro3e that the $VA an ther-al e3aporation -ethos are applica#le +or Be eposition #ecause the4 are clean -ethos o+ eposition in high 3acuu- conitions. $he -ean eposition rates 7ere  R /. n-s +or Be epo'sition using $VA -etho an a#out 1 R /. n-s +or Be eposition #4 ther-al e3aporation in 3acuu-.$he results o#taine +ro- the -easure-ents -ae on the Be +il-s pro3e that the structures present'"-ooth sur+aces'Figh ensit4'Figh purit4 o+ the +il-s 'Goo ahesion o+ the +il-s to the su#strate.'Goo resistance to ther-al tests. References 10 $. Firai, . %5ato, P. Ma*erus, Materials $ransactions,  82//9 12'2.20 F. Maier, Materials "cience oru- ': 82//9 1='1=@2.=0 F. Maier, &. !eu, F. Greuner, Ch. Fop+, G. . Mat'the7s, G. Pia55a, $. Firai, G. Counsell, . Courtois, &. Mitteau, %. Gauthier, J. Lin(onen, G. Maaluno, V. Phil'ipps, B. &iccari, C. &uset, %DA'J%$ $ea-, ;$ungsten coatings +or the J%$ I$%&'li(e )all Pro*ect<, presente at 1th P"I con+erence, Fe+ei China, Ma4 2//.0 F. Greuner, F. Bolt, B. BSs7irth, $. ran(e, P. Mc!eel4, ". #er-a4er, !. &ust, &. "TU, usion %ng. Des. ': 82//9 ==/. 0 F. Maier, J. Luthin, M. Baen, J.Lin(e, .och, F. Bolt, "ur+ace an Coatings $echnolog4 P. Ma*erus, $. Firai, J. Lin(e, ). Thnlein, M. &Sig, &. Du7e, usion Design an %ng. ': 82//9 ='=:.0 M. &u#el, J.P. Coa, . "tenstrS-, P. )ienhol, J. Li(onen, G.. Matthe7s,V. Philipps, 3er3ie7 o+ tracer techni6ues in stuies o+ -aterial erosion, re'eposition an +uel in3entor4 in to(a-a(s, J. !ucl. Mater.=2:'=== 82//9 :'::.0 J.P. Coa, J. Li(onen, M. &u#el, %. Vainone'Ahlgren, D.%. Fole, $. "a*a3aara, $. &en3all, G.. Matthe7s, 3er'3ie7 o+ -aterial re'eposition an +uel retention stuies at J%$ 7ith the Gas BoE i3ertor, !ucl. usion  82//9 =/'=.@0 . "ch-i, M.J. Bal7in, &.P. Doerner, In+luence o+  #er4lliu- plas-a seeing on the erosion o+ car#on, J.  !ucl. Mater. =='==: 82//9 @2'@. :0  C. P. Lungu, I. Mustata, G. Musa, A. M. Lungu, V. Zaroschi, . I7asa(i, &. $ana(a, . Matsu-ura, I. I7ana'ga, F. $ana(a, $. i, . u*ita "ur+. an Coat. $echn., 200  82//9 =::. 1/0  C. P. Lungu, I. Mustata, V. Zaroschi, A. M. Lungu, P. Chiru, A. Anghel, G. Burcea, V. Bailescu, G. Dinuta, . Din, JAM,   82//9 @@.110 C P Lungu, I Mustata, V Zaroschi, A M Lungu, A Anghel, P Chiru, M. &u#el, P. Coa, G  Matthe7s an J%$'%DA contri#utors,  P   HYS  . S  R . 2// !12"  1
Search
Similar documents
View more...
Tags
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks