Effect of Additives Nb2O5 and Cr2O3 on Creep of UO2

BCCBD%)EC)9??A%AFB!)GH

E

9G?)D1

E

)EG)D$BBI)EC)3E

)

9J)$J)"*//#-;2'_{)*+4))KJ)EJ))L.1+M@#/0};)

"

#"_{$%&'(%)"*+,-'./.01+2"34!"5662&/&"7,1+',+"8&9:!"7;<=>#"?@"5662&/&!"7A+B+'"}

C"_{D&(+91&/2"7,1+',+!"D&/)E"5'1F+921(G!"7;<CH>"HI"D&/)E!"7A+B+'"}

"

)

9N!%$9D%)

" "

*-+",9++6".J"5KC"B.6+B"A1(-"LMCK>".9"N9CK@"-&2"M++'"&22+22+B"%21'0"&"6.1'("B+J+,(").B+/"M&2+B".'"(-+"

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

A1(-" &" F&9G1'0" 09&1'" 21U+" &(" B1JJ+9+'(" (+)6+9&(%9+2" &'B" &66/1+B" 2(9+22+2P" *-+" ,9++6" 9&(+" 1',9+&2+2" 210'1J1,&'(/G" A1(-" (-+" B.6&'(" ,.',+'(9&(1.'" &'B" (-+" ).B+/!" &J(+9" &" ).B1J1,&(1.'" .J" (-+" ,9++6" 9&(+" ,.+JJ1,1+'(!"9+(9.B1,("(-+")+&2%9+B"B&(&"2&(12J&,(.91/GP"

)

AG%$E?3D%AEG)

"

V.61'0"(-+"9+&,(.9"J%+/"5KC)A1(-"&"2)&//"&).%'(".J",+9(&1'")+(&/".S1B+2!"2%,-"&2)LMCK>".9"N9CK@!"A1//"

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

&JJ+,(".(-+9"5KC)J%+/"69.6+9(1+2!"&).'0"(-+)"J1221.'"69.B%,("0&2"M+-&F1.%9"QD&221-!"CH#[RP"

"

*-+"9+/&(1.'2-16"M+(A++'"(-+"2+/J<B1JJ%21.'"&'B",9++6".J"5KC"12"A+//<:'.A'\"2++"+P0P"Q]9.2("&'B"32-MG"

#X?C!"^'.99"+("&/P"#X?XRP"8&9(1,%/&9/G!"(-+"2(9.'0"B+6+'B+',+".J"%9&'1%)"2+/J<B1JJ%21.'"&'B",9++6"9&(+".'" (-+" .SG0+'" ,-+)1,&/" 6.(+'(1&/" 1'" %9&'1%)" .S1B+!" 1'" A-1,-" &" 2/10-(" 1',9+&2+" 1'" .SG0+'" ,.',+'(9&(1.'" M+G.'B"2(.1,-1.)+(9G!"/+&B2"(."&"/&90+"1',9+&2+"1'"B1JJ%21F1(G"&'B",9++6"9&(+"QD&(U:+"#XIXRP"*-+",9++6".J"

5KC"B.6+B"A1(-"LMCK>"%6"(."#PH")./T"1'"(-+"2(9+22"9&'0+"HP><XH"D8&"&("(+)6+9&(%9+2"M+(A++'"#[CC"&'B"

#>=@" ^" -&2" M++'" 2(%B1+B" MG" 7&AM91B0+" +(" &/P" Q#X?#RP" *-+2+" A.9:+92" .M2+9F+B" (-&(" LMCK>"B.61'0" ,&'"

,&%2+"&"210'1J1,&'("1',9+&2+"1'"(-+"2(+&BG<2(&(+",9++6"9&(+"2."/.'0"&2"'1.M1%)"1.'"12")&1'(&1'+B"1'"(-+"LM>__"

F&/+',+" 2(&(+P" *-+" +JJ+,(" .J" .SG0+'" ,-+)1,&/" 6.(+'(1&/" .'" (-+" ,9++6" 9&(+" .J" LMCK><B.6+B" 5KC" A&2"

1'F+2(10&(+B"MG"31'2,.%0-"+("&/P"Q#X?#R!"A-.".M2+9F+B"(-&(",9++6"9&(+"%'B+9"M.(-"(+'21/+"&'B",.)69+221F+" /.&B1'0" A&2" +S(9+)+/G" 2+'21(1F+" (." (-+" ,-+)1,&/" 6.(+'(1&/" .J" .SG0+'!" 1P+P" &" 2/10-(" 1',9+&2+" 1'" (-+" /&((+9" `%&'(1(G"9&12+B"(-+",9++6"9&(+"MG"(A.".9B+92".J")&0'1(%B+P"31'2,.%0-"+("&/P"Q#X?#R"&22.,1&(+B"(-12"+JJ+,(" A1(-"(-+"J.9)&(1.'".J"LM[__"1.'P"

"

32<J&M91,&(+B!" 1P+P" %'199&B1&(+B!" 5KC"J%+/" ,.'(&1'2" (-+" %2%&/" 6.1'(" B+J+,(2" 2%,-" &2" ,&(1.'" &'B" &'1.'"

F&,&',1+2"&'B"1'(+92(1(1&/2P"Y'"&BB1(1.'"(."(-+2+!"(-+",.)M1'&(1.'".J"2%,-"6.1'("B+J+,(2"12"&/2.".J"69+F&/+'(!" +26+,1&//G"A-+'"5KC"12"199&B1&(+BP"*-+2+"B+J+,(2",.)6912+"(-+"]9+':+/"6&192!"+&,-")&B+"%6".J"&"F&,&',G"

9+0%/&(+"(-+".SG0+'"(.")+(&/"9&(1."1'"(-+")&(+91&/!"1P+P"(-+"Kb5"9&(1."1'"5KCP"3BB1(1F+2"2%,-"&2"LMCK>"&'B"

N9CK@"&JJ+,("(-+"Kb5"9&(1."&'B"(-+9+MG",-&'0+"(-+",.',+'(9&(1.'".J"(-+"6.1'("B+J+,(2P"

"

O+9+!"A+",.'21B+9"&"6.1'("B+J+,(").B+/!"M&2+B".'"(-+"/&A".J")&22"&,(1.'!"(."9+/&(+"(-+",.',+'(9&(1.'2".J" 6.1'(" B+J+,(2" (." (-&(" .J" B.6&'(2" QLMCK>"&'B" N9CK@R" 1'" 5KCP" *-+" ).B+/" 12" %2+B" (." +S69+22" (-+" /&((1,+"

B1JJ%21.'",.+JJ1,1+'(2".J"(-+"6.1'("B+J+,(2"&2"&"J%',(1.'".J"B.6&'(",.',+'(9&(1.'!"A-1,-"1'"(%9'"12"%2+B"(." ,&/,%/&(+"(-+",9++6"2(9&1'"9&(+"&2"&"J%',(1.'".J"B.6&'(",.',+'(9&(1.'P"c+"6.21("(-&("(-+"2+/J<B1JJ%21.'".J"5" 1'"(-+"+S(91'21,"9+01.'" 12"F1&"5[__{"F&,&',1+2" J.9"LM}

CK><B.6&'("&'B"F1&"5[_"1'(+92(1(1&/2" J.9"N9CK@<B.6&'(P"

c+"&22%)+"(-&("(-+"/&((1,+"L&M&99.<O+991'0"B1JJ%21.'&/",9++6")+,-&'12)"Q32-MG"#XIXR"12"69+F&/+'(".F+9" (-+"(+)6+9&(%9+"&'B"2(9+22"9+01.'".J"1'(+9+2("J.9"(-+"2G2(+)2"%'B+9",.'21B+9&(1.'P"

" "

%OB)IEAG%&?BCBD%)9G?)D$BBI)"E?BK)

"

*-+" ,.'21B+9+B" 6.1'(<B+J+,(" ).B+/" A&2" .9101'&//G" B+F+/.6+B" MG" a1B1&9B" Q#XIIR" J.9" ,&/,%/&(1.'" .J" 2+/J< B1JJ%21.'" .J" %9&'1%)" 1'" 5KC!xP" O+9+!" A+" &B&6(" (-12" ).B+/" (." (-+" ,&2+" .J" )+(&/<.S1B+" &BB1(1F+2" .J" (G6+"

DCK>"Q6+'(&F&/+'(R"&'B"DCK@"Q(91F&/+'(R!"A-+9+"D"2(&'B2"J.9")+(&/!"1'"5KCP"Y'"(-+"a1B1&9B"6.1'(<B+J+,("

).B+/!" A-1,-" ,&'" M+" B+91F+B" J9.)" (-+" /&A" .J" )&22" &,(1.'" Q2++" +P0P" O&G+2" &'B" 7(.'+-&)" #X?>R!" (-+" ,.',+'(9&(1.'2".J"]9+':+/"&'B"7,-.((:G"B+J+,(2"1'"5KC!x"-./B"&2"J.//.A2"

"

" eK_vdeK_id"K_#!" Q#&R"

" e5_vde5_id"K_C!" Q#MR"

" _{eK d}C_{e5 d K@}

v

v " !" Q#,R"

"

A-+9+"eKvd"&'B"eKid"&9+"(-+",.',+'(9&(1.'2".J".SG0+'"F&,&',1+2"&'B"1'(+92(1(1&/2!"9+26+,(1F+/G!"&'B"2."&9+"

d 5

e _v "&'B"e5_id"J.9"%9&'1%)!"K_n "+S6Q$#E_nR!"#"#bk_BT!"k_B12"(-+"4./(U)&''",.'2(&'(!"T12"(-+"&M2./%(+" (+)6+9&(%9+!"&'B"E_n"12"(-+"J.9)&(1.'"+'+90G""J.9"(-+"9+26+,(1F+"6.1'(<B+J+,(P";`%&(1.'2"Q#&R"&'B"Q#MR"&9+" J.9" (-+" .SG0+'" &'B" %9&'1%)" ]9+':+/" 6&192" QB+J+,(2R!" A-+9+&2" Q#,R" 12" J.9" (-+" 7,-.((:G" B+J+,(P" *G61,&/" '%)+91,&/"F&/%+2"J.9"E_n"&9+"01F+'"1'"*&M/+"#\"A+"%2+"-+9+"E#"@P>!EC"XP>! E@"IP>+fP"Y'"&BB1(1.'!"&"

M&/&',+"+`%&(1.'"J.9",.',+'(9&(1.'"&'B"2(.1,-1.)+(9G"'++B2"(."M+"2&(12J1+B!"'&)+/G" "

" Ce5_vd%eK_id"Ce5_id%eK_vd!x!" QCR"

"

A-+9+"gx"B+'.(+2"(-+"'.'2(.1,-1.)+(9G"6/%2"1)6%91(1+2P"]9.)"(-+"+`%&(1.'2"J.9"(-+"Kb5"9&(1."&2"&"J%',(1.'" .J"B.6&'(",.',+'(9&(1.'"QD&221-"CH#>R"&'B"(-+"9+/&(1.'2"1'"Q#&R<Q#,R!"(-+"J.9)%/&2"J.9"(-+",.',+'(9&(1.'2" .J".SG0+'"&'B"%9&'1%)"F&,&',1+2"&'B"1'(+92(1(1&/2"1'"(+9)2".J"(-+"B.6&'(",.',+'(9&(1.'",&'"M+".M(&1'+Bh" "

" _v "

&

'

C _I[

? # d K

e !" Q@R"

"

C

# C

@ I[

I[ d 5 e

$

() * +,

- _{% !}

" K y K y

v !" Q[R"

"

d K be d K

e _i "K_{# v} "&'B"e5_id"K_Cbe5_vdP"O+9+!"y"12"(-+")./+"J9&,(1.'".J"DCK>".9"DCK@"1'"5KC"&'B"(-+")1'%2"

210'"12"J.9"(-+"J.9)+9"&'B"(-+"6/%2"210'"J.9"(-+"/&((+9!"9+26+,(1F+/GP"*-+2+"9+/&(1.'2"+S-1M1("(-&("M.(-"e5vd"

`%&'(1(1+2\"A-1/+"(-+",.99+26.'B1'0"M+-&F1.%9"J.9"e5id&'B"eKvd12"F1,+"F+92&P"]%9(-+9).9+!"(-+"

&22.,1&(1'0"(9+'B"J.9"(-+"DCK@"B.6&'("12"(-+".66.21(+P"

"

*&M/+"#h"].9)&(1.'"+'+901+2"Q+fR".J"(-+",.'21B+9+B"6.1'(<B+J+,(2"1'"5KC!"2++";`2P"Q#&R<Q#,RP"

;S6+91)+'("F+92%2"2+F+9&/"J192(<691',16/+2",.)6%(&(1.'2h"ii3"Q0+'+9&/1U+B"09&B1+'("&669.S1)&(1.'R!" aV3"Q/.,&/"B+'21(G"&669.S1)&(1.'R!"U2(&'B2"J.9"(-+"O%MM&9B").B+/."

"

D+(-.B" _E#" E_C" E_@" 7.%9,+"

;S6+91)+'(" @<[" XP>" I<=" D&(U:+"Q#X?=R" D.((<a1((/+(.'" [PX# #XP@@ ##P[= j&,:2.'"+("&/P"Q#X?=R"

ii3" @PI" ##P?" >PI" ]9+G22"+("&/P"QCHH>R" ii3_5" [PH" #[PC" =PC" i%6(&"+("&/P"QCHH=R" ii3_5" @PX> #>PH? =PI" L+91:&9"+("&/P"QCHHXR" aV3_5" [PCI =PI>" #P>C" 3'B+922.'"+("&/P"QCH##R" "

"

3,,.9B1'0"(."a1B1&9B"Q#XIIR!"(-+"2+/J<B1JJ%21.'".J"5"1'"5KC_S")&G"M+"9+/&(+B"(."(-+"B+J+,(",.',+'(9&(1.'!"

1P+P" A-+'"x.H!" 1(" 12" (-9.%0-" 5[_" F&,&',1+2" &'B" A-+'"x/H!" 1(" 12" MG" 5[_"1'(+92(1(1&/2P" 71',+" &" (91F&/+'("

.S1B+"&BB1(1F+!"1'"0+'+9&/!")&:+2"5KC"-G6.2(.1,-1.)+(91,!"A+"2%66.2+"(-&("(-+"%9&'1%)"B1JJ%21.'"12"F1&"

(-+"1'(+92(1(1&/2P"K'"(-+".(-+9"-&'B!"&"6+'(&F&/+'(".S1B+"&BB1(1F+")&:+2"5KC"-G6+92(.1,-1.)+(91,!"(-+9+MG"

,&(1.'" B1JJ%21.'" )&G" .,,%9" MG" %9&'1%)" F&,&',1+2P" O+',+!" (-+" %9&'1%)" .9" .SG0+'" /&((1,+" B1JJ%21.'" ,.+JJ1,1+'("DL",&'"M+"9+/&(+B"(."Q.9"2,&/+B"A1(-R"(-+",.',+'(9&(1.'".J"B+J+,(2"&2"

"

" uv _Uve5_vd

L D

D " !" Q>&R"

" ov _OveK_vd

L D

D " !" Q>MR"

" ui _Uie5_id

L D

D " !" Q>,R"

"

A-+9+!" +P0P" D_Ov" 12" (-+" k1'(91'21,k" B1JJ%21.'" ,.+JJ1,1+'(" J.9" .SG0+'" F&,&',1+2" &'B" 2." J.9(-\" " /1:+A12+" 9+/&(1.'2" ,&'" M+" 9+6+&(+B" J.9" (-+" ,.99+26.'B1'0" 1'(+92(1(1&/2P" 7%M2(1(%(1'0" '.A" J.9"e5vd!"eKvd" &'B"e5id"

J9.)";`2P"Q@R<Q[R"+(,P"1'"Q>&R<Q>,R"01F+2"(-+"B.6&'(",.',+'(9&(1.'"B+6+'B+'("B1JJ%21.'",.+JJ1,1+'(2"1'"(-+" Q5#$y!DyRKC!S" ,.)6.%'BP" *-+" (+)6+9&(%9+" B+6+'B+',+" .J" (-+" 1'(91'21," B1JJ%21.'" ,.+JJ1,1+'(2" 1'" 5KC"

B+(+9)1'+B"MG")+&2%9+)+'(2"%2+B"1'".%9",.)6%(&(1.'2"&9+"01F+'"1'"*&M/+"CP""Y("12"'.(+B"(-&("&,,.9B1'0"(." (-+"+)6191,&/"9+/&(1.'2"1'"*&M/+"C!"D_Ov12"&M.%("(+'".9B+92".J")&0'1(%B+"/&90+9"(-&'"D_Ui1'"(-+"(+)6+9&(%9+" 9&'0+".J"1'(+9+2("Q#[HH<CHHH"^RP"

"

Y("12"&'"+)6191,&/"J&,("(-&("(-+"2(+&BG"2(&(+"(-+9)&/",9++6"9&(+".J"5KC"12"2(9.'0/G"&JJ+,(+B"MG"(-+"&BB1(1.'".J"

B.6&'(2"2%,-"&2"LMCK>"Q7&AM91B0+"+("&/P"#X?#R".9"N9CK@"QV%0%&G"+("&/P"#XXIRP"*-+"2(+&BG"2(&(+",9++6".J"

.S1B+2"A1(-"J/%.91(+"2(9%,(%9+!"+P0P"5KC!"*-KC!"N+KC!"&("-10-"(+)6+9&(%9+2!"(G61,&//G"&M.F+"HP[T_m!"A-+9+"

m

" " "

*&M/+"Ch"V1JJ%21F1(G".J"6.1'("B+J+,(2"1'"'+&9"2(.1,-1.)+(91,"5KC\"D"D_H+S6Q$QDbTRP" "

8.1'("B+J+,(" *+)6+9&(%9+

H

D " Q_D" W+J+9+',+"

<" ^" )C_{b2" ^" ;S6+91)+'("}

KF" #[II<#?@?" 010234$56 >??? ^1)<K/&'B+9"Q#X?=R"

51" #=C@<#X=@" 014234$33 @>CCX a1B1&9B"Q#XIIR"

5F" #=C@<#XC@" 317234$8" >[@I@ ]9.2(<32-MG"Q#X?CR"

5Fl" #I=@<#XC@" 7140234$9 [[IX@ O&A:1'2<3/,.,:"Q#XI?R"

""5Fll" #[=@<#?=@" 718234$3:" CH??? D&(U:+"Q#XIXR" lY'"5KCPH#\"llY'"5KC_LMCK>P"

"

" "

" _L

g B

a

A D

Td k C

;

<

"

A-+9+"<!"12"(-+"2(9&1'"9&(+!"="n"[HPX"o@"12"(-+"F./%)+".J"(-+"5KC")./+,%/+!"d_g12"(-+"09&1'"21U+!";_a12"(-+"

&66/1+B" 2(9+22!" C_A12" &" )&(+91&/" B+6+'B+'(" &BZ%2(&M/+" 6&9&)+(+9!" &'B" Dm_L" 12" (-+" ,.)M1'+B" B1JJ%21.'" ,.+JJ1,1+'(2".J"(-+",&(1.'"&'B"&'1.'"&,(1'0"1'"6&9&//+/"Q^'.99"+("&/P"#X?XR"

"

" _o

L u L

o L u L L

D D

D D D

% "

m _{P" Q=R"}

"

Y'"6./G,9G2(&//1'+"5KC"&("2.)+A-&("/.A+9"(+)6+9&(%9+2!"B1JJ%21.'&/",9++6",&'"M+"B.)1'&(+B"MG"(-+"J/.A"

.J"1.'2"1'"(-+"09&1'"M.%'B&9GP"*-12"J/.A"12",&//+B"(-+"N.M/+",9++6!"&'B"2,&/+2"&2"m _b @

g

B d

D "1'2(+&B".J"DmBbdgC"

&2"1'"(-+"L&M&99.<O+991'0",9++6P""" "

BF9K39%AEG)EC)D$BBI)BPIB$A"BG%!) )

Y'"(-+"J.//.A1'0"(A."2%M2+,(1.'2!"A+"&66/G";`2P"QIR<Q=R"(."+F&/%&(+"+S6+91)+'(&/"9+2%/(2".'",9++6".J"5KC"

B.6+B"A1(-"2)&//",.',+'(9&(1.'2".J"LMCK>"&'B"N9CK@P"

Creep of UO2 doped with Nb2O5" "

3"2G2(+)&(1,"A.9:"&).'0"(-+"+&9/G"(-+9)&/",9++6"2(%B1+2"12"(-+"#X?#"6&6+9".J"7&AM91B0+"&'B",.A.9:+92" Q#X?#R"A-."1'F+2(10&(+B"(-+",9++6"B+J.9)&(1.'".J"5KC"J%+/"B.6+B"A1(-"LMCK>"1'"(-+"2(9+22"9&'0+".J"HP><XH"

D8&" &(" (+)6+9&(%9+2" J9.)" #[CC" (." #>=@" ^P" N.)69+221.'" ,9++6" (+2(2" A+9+" ,&991+B" .%(" %'B+9" &" ,.'2(&'(" /.&B" 1'" &().26-+9+" .J" J/.A1'0" 6%91J1+B" &90.'P" *-+G" 69.F1B+" B&(&" .'" (-+" ,9++6" 9&(+" .J" 2+F+'" B.6&'(" ,.',+'(9&(1.'2"J9.)"HPC")./T"(."#PH")./T"LMCK>P"*-+"2&)6/+2"(-&("A+9+"+S&)1'+B"-&B"B1JJ+9+'(")+&'"

Q/1'+&9" 1'(+9,+6(R" 09&1'" 21U+2!" B+61,(+B" 1'" ]10P" #3P" " Y(" 12" 2++'" (-&(" (-+" 09&1'" 21U+" 2(+&B1/G" 1',9+&2+" A1(-" LMCK>",.',+'(9&(1.'"%'(1/"1("/+F+/2".JJ"&("&",.',+'(9&(1.'".J"&M.%("HP>")./T"(."">"@H"p)P""3("-10-"2(9+22+2"

B12/.,&(1.'<,.'(9.//+B",9++6P"3("/.A+9"2(9+22+2"Q/6=H"D8&R!"&"9.%0-/G"/1'+&9"B+6+'B+',+".'"2(9+22!"(G61,&/" .J" B1JJ%21.'" ,9++6" A&2" .M2+9F+BP" 32" '.(+B" 1'" Q7&AM91B0+" +(" &/P" #X?#R!" 1(" 12" (-+" /.A+9" 2(9+22" 9+01.'2!" (G61J1+B" MG" &" /1'+&9" 2(9+22" B+6+'B+',+" .J" ,9++6" 9&(+!" 1'" A-1,-" (-+" ).2(" 69.)1'+'(" ,9++6" ).B+2" .,,%9" B%91'0"'.9)&/"9+&,(.9".6+9&(1'0",.'B1(1.'2P"

"

" " 9" " " " " N"

0 0.002 0.004 0.006 0.008 0.01

5 10 15 20 25 30 35 40 45 50 [Nb

2O5]

Mean grain size (

µ

m)

Measured Interpolated

""""""""

0 0.002 0.004 0.006 0.008 0.01

10−10 10−9 10−8 10−7 10−6 10−5 10−4 [Nb

2O5] Creep rate (1/s) Measured

Calculated Calculated, d_g=15 µm

Calculated, d_g=30 µm

" "

]10%9+"#P""Q9R"D+&2%9+B"09&1'"21U+"F+92%2"LMCK>")./+"J9&,(1.'".J"5KC"B.6+B"1'"2&)6/+2"(+2(+B"MG"

7&AM91B0+"+("&/P"Q#X?#RP"QNR"D+&2%9+B",9++6"9&(+2"Q7&AM91B0+"+("&/P"#X?#R"F+92%2",&/,%/&(+B"F&/%+2"Q-+9+R" &2"&"J%',(1.'".J"LMCK>")./+"J9&,(1.'"1'"5KC"&("&'"&66/1+B"2(9+22".J"CH"D8&"&("#>C@"^P""*-+"B&2-+B"&'B"

B&2-<B.(",%9F+2"2-.A",.)6%(&(1.'2")&B+"&(",.'2(&'("09&1'"21U+2P"" "

7&AM91B0+"+("&/P"Q#X?#R"%2+B"(-+"L&M&99.<O+991'0",9++6"J.9)%/&"A1(-"/&((1,+"B1JJ%21F1(G!"&2"1'";`P"Q>&R!"(." +F&/%&(+" (-+19" +S6+91)+'(&/" B&(&P" O.A+F+9!" (-+G" B." '.(" 69.F1B+" '%)+91,&/" F&/%+2" J.9" (-+" J.9)&(1.'" +'+901+2" .J" (-+" B+J+,(2" '.9" 26+,1JG" (-+" /&((1,+" B1JJ%21F1(G" .J" %9&'1%)" F&,&',1+2P" a1:+A12+!" (-+G" B." '.(" +S6/1,1(/G"01F+"(-+"J%//"+S69+221.'"J.9"e5vd!"A-1,-"(-+G"-&F+"2%66.2+B/G"%(1/1U+BP"71',+"7&AM91B0+"+("&/Pq2"

A.9:".JJ+92"&"2%1(&M/+"M+',-)&9:"J.9"(-+").B+/"%2+B"-+9+!"A+"J.%'B"1(2"9+&669&12&/"`%1(+"A.9(-A-1/+P" "

c+" -&F+" %2+B" ;`2P" Q>&R!" QIR<Q=R" (." 9+(9.B1,(" (-+" ,9++6" 9&(+" &2" &" J%',(1.'" .J" LMCK>",.',+'(9&(1.'" &'B"

(+)6+9&(%9+P"L.(+"(-&("21',+" u L o

L D

D .. "(-+'" m uv _Uve5_vd

L u L

L D D D

D > A " !"&'B"D_Uv"12"26+,1J1+B"1'"*&M/+"C" QD&(U:+" #XIIRP" *-+" U+9." B.6&'(" ,.',+'(9&(1.'" /1)1(" J.9" e5vdA5vQH!TR" &(" #>C@" ^" 12"

#H C

@b #P#?C #H

$ 2 " K K !"A-1,-"'++B2"(."M+"&,,.%'(+B"J.9"MG"2,&/1'0"(-+"/&((1,+"B1JJ%21F1(GP"D.9+"+S6/1,1(/G" " " R ! H Q 5 R ! Q 5 R Q R ! Q T T y T D T y D v v Uv uv

L " !" Q?R"

"

A-+9+" y" 12" (-+" B.6&'(" ,.',+'(9&(1.'P" ]%9(-+9).9+!" 1'" .%9" ,.)6%(&(1.'2" J.9" LMCK>!" A+" ,-..2+" #[C

P >

"

A

C 1'";`P"QIR"&'B"&22%)+"&'"1'1(1&/"1)6%91(G"/+F+/".J":14234$8")./+"J9&,(1.'P"*-+"9+2%/(2".J".%9" ,.)6%(&(1.'2" (.0+(-+9" A1(-" )+&2%9+)+'(2" &9+" B+61,(+B" 1'" ]10P" #4P" Y(" 12" 2++'" J9.)" (-12" J10%9+" (-&(" (-+" ,&/,%/&(+B",9++6"9&(+2"J.//.A"(-+"(9+'B".J")+&2%9+)+'(2"A1(-"&'".F+9+2(1)&(1.'"&("HPH#")./+"J9&,(1.'".J" LMCK>P"L+F+9(-+/+22!".%9"9+2%/(2"&9+",.)6&9&M/+"(.!"M%("'.("(-+"2&)+"&2"(-.2+"9+6.9(+B"MG"7&AM91B0+"+("&/P"

Q#X?#RP""Y'"]10P"#4"J.9"(-+"2&:+".J",.)6&912.'!"A+"-&F+"&/2."6/.((+B"(-+"9+2%/(2".J",&/,%/&(1.'2",&991+B".%(" A1(-",.'2(&'("09&1'"21U+2".J"#>"p)"&'B"@H"p)P"

Creep of UO2 doped with Cr2O3" "

7G2(+)&(1," -10-<(+)6+9&(%9+" ,9++6" 9&(+" )+&2%9+)+'(2" &2" &" J%',(1.'" (+)6+9&(%9+" &'B" &66/1+B" 2(9+22" .'" B.6+B"5KC!"1'"6&9(1,%/&9"A1(-"N9CK@"&BB1(1F+!"&9+"F+9G"9&9+"1'"(-+".6+'"/1(+9&(%9+!"B+261(+"1(2"&66/1,&(1.'2"1'"

,.))+9,1&/"9+&,(.9"J%+/P"*-+9+"12!"-.A+F+9!"&"#XXI"+S6+91)+'(&/"2(%BG"MG"V%0&G"+("&/P"Q#XXIR".'",9++6".J" 5KC<N9CK@",.)6.%'BP"Y'").9+"B+(&1/!"(-+19",9++6"(+2(2"A+9+"B.'+"MG",.)69+221.'"%'B+9"&90.'".9"9+B%,1'0"

Q-GB9.0+'&(+B" &90.'R" )1/1+%" &(" B1JJ+9+'(" (+)6+9&(%9+2" #IC@<#XC@" ^" .'" %'199&B1&(+B" 26+,1)+'2P" *-+" )+&2%9+)+'(2" .J" ,9++6" 9&(+" A+9+" B.'+" %'B+9" &" ,.'2(&'(" (+)6+9&(%9+" &(" 2(9+22+2" F&9G1'0" J9.)" CH" (." =H" D8&P"*-+"N9CK@",.',+'(9&(1.'2".J"5KC"26+,1)+'2"A+9+"eHPH!"HPHC>!"HPHI!"HP#!"HPCd"A(TP"*-+"09&1'"21U+"&2"

&"J%',(1.'".J"N9CK@"1'")./+"J9&,(1.'"J.9"(-+"26+,1)+'2"12"B+61,(+B"1'"]10P"C3P"3BB1(1.'".J"N9CK@"2(9.'0/G"

1',9+&2+2"(-+",9++6"9&(+"9+/&(1F+"(."(-&(".J"6%9+"5KC"1'"&90.'"&().26-+9+P"

"

" " 9" " " " " N"

0 1 2 3 4

x 10−3 0 10 20 30 40 50 60 70 80

[Cr₂O₃]

Grain size (

µ

m)

Measured Interpolated

""""""""

0 1 2 3 4

x 10−3 10−10 10−9 10−8 10−7 10−6 10−5

[Cr₂O₃]

Creep rate (1/s)

T = 1573 K T = 1673 K T = 1773 K

" "

]10%9+"CP"Q9R"D+&2%9+B"09&1'"21U+"F+92%2"N9CK@")./+"J9&,(1.'".J"5KC"B.6+B"1'"2&)6/+2"QV%0&G"+("&/P"

#XXIRP"QNR"D+&2%9+B",9++6"9&(+2"QV%0&G"+("&/P"#XXIR"F+92%2",&/,%/&(+B"F&/%+2"-+9+"Q_R"&2"&"J%',(1.'".J"

N9CK@")./+"J9&,(1.'"1'"5KC"&("&'"&66/1+B"2(9+22".J"[>"D8&"&("B1JJ+9+'("(+)6+9&(%9+2P""

" "

O+9+!" A+" &22%)+" (-&(" B1JJ%21F+" ,9++6" 12" 0.F+9'+B" MG" (-+" B1JJ%21.'" .J" %9&'1%)" 1'(+92(1(1&/2" &'B" .SG0+'" F&,&',1+2!"1P+P"A+"-&F+"%2+B";`2P"Q>MR<Q>,R"&'B"QIR<Q=R"(."9+(9.B1,("(-+",9++6"9&(+"&2"&"J%',(1.'".J""N9CK@"

)./+"J9&,(1.'"&'B"(+)6+9&(%9+P""O.A+F+9!"21',+"(-+" ,&(1.'"B1JJ%21F1(G"12")%,-"/.A+9"(-&'"(-&(".J"&'1.'!" .'/G"(-+"J.9)+9"A1//",.'(9./"B1JJ%21.'</1)1(+B"B+J.9)&(1.'!"1P+P" u

L o

L D

D .. "(-+'" m Uie5id

ui L u L

L D D D

D > A " !"

&'B"D_Ui"12"26+,1J1+B"1'"*&M/+"C"Qa1B1&9B"#XIIRP""*-+"U+9."B.6&'(",.',+'(9&(1.'"/1)1(2"e5_idA5_iQH!TR"&("

(-+",.'21B+9+B"(+)6+9&(%9+2"'++B"(."M+"&,,.%'(+B"J.9"MG"2,&/1'0"(-+"/&((1,+"B1JJ%21F1(G"&2"M+J.9+" " " R ! H Q 5 R ! Q 5 R Q R ! Q T T y T D T y D i i Ui ui

L " P" QXR"

"

O+9+!" A+" -&F+" 2+/+,(+B" (-.2+" B&(&" J9.)" QV%0%&G" +(" &/P" #XXIR" (-&(" 2++)" (." M+" ).9+" &66/1,&M/+" (." %9&'1%)b.SG0+'" 2+/J<B1JJ%21.'!" 1P+P!" (-.2+" &(" (+)6+9&(%9+2" #>=@" (." #==@" ^" &'B";a "[>" D8&P" *." 0+(" &"

0..B"J1(".J";`P"QIR"(."+S6+91)+'(&/"B&(&"&("(-+"B1JJ+9+'("(+)6+9&(%9+2!"A+"A+9+",.)6+//+B"(."9+&BZ%2("(-+" ,9++6" J&,(.9"C_A&,,.9B1'0/GP"*-&(" 12!" A+" %2+B"CA"@>!"CA"#>H" &'B"CA"[HH" &("T"#>=@!"T "#I=@"

&'B"T "#==@" ^!" 9+26+,(1F+/GP" ]%9(-+9).9+!" (." B&)6+'" (-+" ,.)6%(+B" F&/%+" .J" (-+" %9&'1%)" 1'(+92(1(1&/" ,.',+'(9&(1.'" &(" (-+" F+9G" /.A" B.6&'(" ,.',+'(9&(1.'!" &2" M+J.9+!" A+" &22%)+B" &'" 1'1(1&/" 1)6%91(G" /+F+/" .J"

"

*-+"9+2%/(2".J".%9").B+/",.)6%(&(1.'2"&9+"69+2+'(+B"1'"]10P"C4!"A-1,-",.)6&9+2"(-+")+&2%9+B",9++6"9&(+" F&/%+2"&0&1'2("(-+",&/,%/&(+B".'+2P""N.'21B+91'0"(-+"%',+9(&1'(G"1'"(-+")+&2%9+)+'(2"Q%6"(."&M.%("!#?TR!" (-+"9+(9.B1,(1.'2"&9+"J&19/G"0..BP"*-+")+&2%9+B"B&(&"B+61,(+B"1'"]10P"#4"&9+"(-+"9+2%/(2".J"B19+,("J1("(."(-+" 9&A"B&(&"&2"01F+'"1'"QV%0%&G"+("&/P"#XXIRP"

" "

?A!D3!!AEG)

"

Frenkel defect formation energy

"

3" :+G" 6&9&)+(+9" 1'" (-+" 6%(&(1F+" ).B+/" 12" (-+" J.9)&(1.'" +'+90G" .9" +'(-&/6G" .J" (-+" .SG0+'" 6&19" ]9+':+/" B+J+,(2" H_F!" -+9+" B+'.(+B" MGE_#\" 2++" *&M/+" #P" *." 1//%2(9&(+" (-12!" A+" -&F+" 6/.((+B" (-+" ,&/,%/&(+B" ,.',+'(9&(1.'".J"(-+"%9&'1%)"F&,&',G"&2"&"J%',(1.'".J"B.6&'("QDCK>"A"LMCK>R",.',+'(9&(1.'"1'"]10P"@3P"Y("

12"2++'"(-&("&"F&91&(1.'".J"@BE#B["+f")&:+2"&"/&90+"1)6&,(".'"(-+",.',+'(9&(1.'".J"(-+"F&,&',1+2P"*-12"

1'"(%9'"210'1J1,&'(/G"&JJ+,(2"(-+"/&((1,+"B1JJ%21F1(G"&'B"(-+9+MG"(-+",9++6"9&(+".J"(-+"J%+/!"2++";`2P"Q=R<Q?RP" "

*-+" F&/%+" .J" E_#AH_F" Q*&M/+" #R" ,&'" M+" )+&2%9+B" J9.)" .SG0+'" B1JJ%21.'" +S6+91)+'(2" .'" '+&9/G" 2(.1,-1.)+(91," 5KC!" A-1,-" 12" F+9G" B1JJ1,%/(" (." )&1'(&1'" B%91'0" (-+" +S6+91)+'(" QD&(U:+" #X?=RP" *&M/+" #"

2-.A2" &" 2+/+,(+B" /12(" .J" F&/%+2",&/,%/&(+B"MG"F&91.%2"B+'21(G"J%',(1.'&/" (-+.9G"&669.S1)&(1.'2".9"V]*2" e+S,+6("j&,:2.'"+("&/P"Q#X?=R!"A-1,-"%2+"(-+"D.((<a1((/+(.'"&669.S1)&(1.'dP"]9.)"(-12"(&M/+!"A+"2++"(-&(" (-+"ii3"9+2%/("Q]9+G22"+("&/P" CHH>R"&09++2"A+//"A1(-"(-+"M+2("+2(1)&(+"F&/%+"9+,.))+'B+B"MG"D&(U:+!" A-+9+&2" (-+" aV3" _"U" 9+2%/(" .J" 3'B+922.'" +(" &/P" QCH##R" ,.'J.9)2" A1(-" (-+" +S6+91)+'(&//G" B+(+9)1'+B" 9+2%/(".J"^1)"&'B"K/&'B+9"Q#X?#RP"L+F+9(-+/+22" J.9H_F!"(-+9+" 12"&"9&'0+".J"F&/%+2!"J9.)" @PI" (."[PX" +f!" 9+2%/(+B"J9.)"F&91.%2",.)6%(&(1.'2P"

"

Effective diffusivity

"

*-+",.'(9.//1'0")+,-&'12)"J.9"B1JJ%21.'&/",9++6"1'"5KC"12"(-+"B1JJ%21.'".J"%9&'1%)P"32",&'"M+"2++'"J9.)"

*&M/+"C!"(-+9+"12"&"/&90+"B126&91(G"M+(A++'"(-+"&,(1F&(1.'"+'(-&/61+2".J"B1JJ%21.'",.+JJ1,1+'(2"9+6.9(+B"MG" F&91.%2"&%(-.92"1'"(-+"/1(+9&(%9+P"*-+G"F&9G"J9.)"#P?"+f"QD&(U:+"#XIXR!"@PX"+f"QO&A:1'2<3/,.,:"#XI?R"(." [P="+f"Q]9.2(<32-MG"#X?CR"J.9"D_Uv&'B"@PH"+f"J.9"D_Ui"Qa1B1&9B"#XIIRP"8/.(2".J"(-+"B1JJ%21.'",.+JJ1,1+'(2" Q*&M/+"CR"F+92%2"(+)6+9&(%9+"9+F+&/"(-+19".F+9&//"B1JJ+9+',+2P"""*-+"1'(91'21,"B1JJ%21.'",.+JJ1,1+'("D_Ui(-&(" A+"-&F+"%(1/1U+B"J.9",9++6".J"N9CK@<B.6+B"5KC"12"/.A+9"(-&'"(-+"D_Uv%2+B"J.9"LMCK><B.6+B"5KC"QD&(U:+"

#XIXRP" " D.9+.F+9!" B+261(+" (-+" /&90+" B1JJ+9+',+" M+(A++'" (-+" &,(1F&(1.'" +'(-&/61+2" J.9"D_Uv.M(&1'+B" MG" D&(U:+" Q#XIXR" &'B" (-&(" J9.)" O&A:1'2<3/,.,:" Q#XI?R!" (-+19" .F+9&//" 9+2%/(2" &9+" '.(" 2." /&90+P" *-+" (A." 9+/&(1.'2",9.22".'+"&'.(-+9"&("&M.%("#=>H"^!"&M.F+"A-1,-"(-+"/&((+9".F+9(&:+2"(-+"J.9)+9P"K'"(-+",.'(9&9G!" (-+"D_Uv9+,.))+'B+B" MG" ]9.2(" &'B" 32-MG" 12" )%,-" /.A+9" (-&'" (-+" .(-+9" (A." QD&(U:+" #XIX!" O&A:1'2< 3/,.,:" #XI?R" M+/.A" #?HH" ^\" 2++" *&M/+" CP" " 8&9(" .J" (-12" B1JJ+9+',+" ,&'" M+" B%+" (." (-+" B1JJ+9+'(" 1)6%91(G" /+F+/2".J"(-+" 5KC"2&)6/+2P""Y'"]10P"@4!"A+"-&F+"6/.((+B"(-+"/&((1,+"B1JJ%21F1(G"&,,.9B1'0" (.";`P"Q?R"&2"&"

J%',(1.'" .J" &" 6+'(&F&/+'(" B.6&'(" ,.',+'(9&(1.'" %21'0" (-+" (-9++" +)6191,&/"D_Uv" F&91&'(2" /12(+B" 1'" *&M/+" C" QD&(U:+"#XIX!"O&A:1'2<3/,.,:"#XI?!"]9.2(<32-MG"#X?CRP"

"

Y'".%9",.)6%(&(1.'2".J"B1JJ%21.'&/",9++6"A+".'/G",.'21B+9+B"(-+"/&((1,+".9"F./%)+"B1JJ%21F1(GD_L!"1P+P"(-+" ,.'(91M%(1.'".J"09&1'<M.%'B&9G",&(1.'"B1JJ%21F1(G"D_B"QN.M/+",9++6R"A&2"'.("(&:+'"1'(."&,,.%'(P""V126&9&(+" F&/%+2"Q399-+'1%2"9+/&(1.'2R".J"D_BJ.9"%9&'1%)"1.'2"1'"5KC"-&F+"M++'"9+6.9(+B"1'"(-+"/1(+9&(%9+"M&2+B".'"

" " "

" " 9" " " " " """""""""N"

0 0.002 0.004 0.006 0.008 0.01

100 102 104 106 108 1010

[M₂O₅]

Normalized concentration, U

v T = 1573 K

E 1 = 3 eV E₁ = 3.5 eV

E 1 = 4 eV

""""""""

0 0.002 0.004 0.006 0.008 0.01

10−18 10−16 10−14 10−12

[M₂O₅]

D L

(m

2 /s)

T = 1573 K,E 1 = 3.5 eV

U

v Mat69

U

v Haw68

U_v McN63

" "

]10%9+"@P"Q9R"N.)6%(&(1.'2".J"(-+"%9&'1%)"F&,&',G",.',+'(9&(1.'"5v"F+92%2"(-+"6+'(&F&/+'("B.6&'("

,.',+'(9&(1.'"1'"5KC"J.9"(-9++"F&/%+2".J"(-+"]9+':+/"&'1.'"6&19"+'+90G"E#"&(""T"#>=@P"QNR"*-+"

,.99+26.'B1'0",.)6%(&(1.'2".J"(-+"/&((1,+"B1JJ%21F1(G"D_L"&("E#"@P>"+f"&'B"T"#>=@!"6+9";`P"Q?R!"J.9" (-9++"+S6+91)+'(&/"1'(91'21,"B1JJ%21F1(1+2".J"5v"h"D&(IX"QD&(U:+"#XIXR!"O&AI?"QO&A:1'2<3/,.,:"#XI?R!"

D,LI@"&((91M%(+B"(."8P"D,L&)&9&""Q]9.2(<32-MG"#X?CR\"2++"*&M/+"CP" "

Effect of temperature and stress

"

a+(" %2" '.A" B12,%22" (-+" +JJ+,(" .J" 2(9+22" .'" ,9++6" 9&(+P" Y(" 12" A+//" :'.A'" (-&(" 2+F+9&/" B+J.9)&(1.'" )+,-&'12)2" &9+" 1'F./F+B" 1'" .S1B+2" A1(-" J/%.91(+" ,9G2(&/" 2(9%,(%9+!" 1'" 6&9(1,%/&9" 5KC"&'B" *-KC" Q]9.2(<

32-MG" #X?CRP" N-&'0+2" J9.)" .'+" )+,-&'12)" (." &'.(-+9" )&'1J+2(" &2" ,-&'0+2" .J" 2/.6+" .'" (-+"/.0<_!" F2P"

;

/.0 "6/.(P"*-+"&,(%&/",-&'0+2"&9+".M2+9F+B"(.".,,%9"2(+&B1/G"9&(-+9"(-&'"&M9%6(/G\"(-+9+J.9+",&%(1.'"'++B2" (."M+"+S+9,12+B"A-+'"+F&/%&(1'0"B&(&"1'"(+9)2".J"&"21'0/+")+,-&'12)"Q^'.99"+("&/P"#X?XRP"V&(&",.'21B+9+B" &2"B1JJ%21.'&/",9++6"2-&//"M+"(-.2+"J.9"A-1,-"(-+"09&1'"21U+"B+6+'B+',+".J"2(9&1'"9&(+"12"F+91J1+BP"3("F+9G" /.A"2(9+22+2!"2.<,&//+B"1'(+9J&,+<,.'(9.//+B"B1JJ%21.'&/",9++6"Q4%9(.'"#X=CR")&G"M+,.)+"1)6.9(&'(P"Y'"(-&(" ,&2+!"(-+"2(9&1'"9&(+"F&91+2"&2"(-+"2`%&9+".J"2(9+22!"1P+P"/.0<_!>C/.0;P"3("-10-+9"2(9+22+2!"B12/.,&(1.'",/1)M" &'B" B12/.,&(1.'" 0/1B+" )+,-&'12)2" A1//" B.)1'&(+!" 1'" A-1,-" (-+" 2(9+22" +S6.'+'(" F&/%+2" .J" (-+" 2(9&1'" 9&(+" F&9G"M+(A++'"n"@&'B"n"["Q^'.99"+("&/P"#X?XRP"

"

3'"&'&/G212".J"7&AM91B0+"+("&/P"Q#X?#R"B&(&".'",9++6".J"5KC"B.6+B"A1(-"LMCK>"1'B1,&(+2"(-&("1'"(-+"2(9+22"

9&'0+".J"#H"(." >H" D8&"J.9"LMCK>",.',+'(9&(1.'2"9&'01'0" J9.)"HP#"(."#PH" )./T"&'B"(+)6+9&(%9+2" J9.)"

#[C@"(."#>C@"^!"(-+",9++6"9&(+"12"/1'+&9/G"69.6.9(1.'&/"(."(-+"&66/1+B"2(9+22P"c1(-"(-+"69+2+'(").B+/!"A+" -&F+",&/,%/&(+B"(-+"(+)6+9&(%9+b2(9+22"B+6+'B+',+".J",9++6"9&(+".J"5KC<HP[")./T"LMCK>"J.9"A-1,-"&"J+A"

+S6+91)+'(&/"B&(&"&9+"9+6.9(+B" 1'" Q7&AM91B0+" +("&/P"#X?#RP" *-+" 9+2%/(2".J".%9",&/,%/&(1.'2"(.0+(-+9"A1(-" +S6+91)+'(&/"B&(&"&9+"69+2+'(+B"1'"]10P"[P"*-+"9+2%/(2"%6"(."&"2(9+22".J"CH"D8&"&9+"J&19!"M%("M+G.'B"(-12" 2(9+22"/+F+/".'/G"B&(&"J.9"#[>@"^"&9+"&F&1/&M/+!"A-1,-".%9",&/,%/&(1.'2".F+9+2(1)&(+P"

" "

0 20 40 60 80 100 10−8

10−7 10−6 10−5 10−4

Stress (MPa)

Creep rate (1/s)

T = 1453 K

T = 1537 K

T = 1563 K

" "

]10%9+"[P"N9++6"9&(+"F+92%2"2(9+22"&("2+F+9&/"(+)6+9&(%9+2"J.9"5KC"<HP[")./T"LMCK>P"*-+"/1'+2"&9+"

,&/,%/&(+B"F&/%+2"Q2./1B"/1'+"#[>@"^!"B&2-+B"#>=@"^!"B&2-<B.("#>I@"^R!""(-+"2G)M./2"&9+")+&2%9+B"F&/%+2" 9+6.9(+B"1'"Q7&AM91B0+"+("&/P"#X?#RP"

) )

DEGDK3?AGQ)$B"9$5!)

"

Y'" (-12" 6&6+9!" (-+" a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`%&(+"J.9"/.A",.',+'(9&(1.'2".J"B.6&'(2!"2&G""BHPH#")./+"J9&,(1.'P"

"

322%)1'0" /&((1,+" B1JJ%21.'&/" J/.A" 1'" (-+" 5KC" 2./1B!" (-+" ,9++6" 2(9&1'" A&2" 9+/&(+B" (." (-+" 6.1'(<B+J+,("

B1JJ%21F1(G!"(-+9+MG"(."B.6&'(",.',+'(9&(1.'!"&'B"&/2."(."09&1'"21U+"F1&"(-+"L&M&99.<O+991'0"J.9)%/&P"*-12" A&2" %2+B" (." +F&/%&(+" 69+F1.%2" ,9++6" +S6+91)+'(2" .'" 5KC"A1(-" B1JJ+9+'(" ,.',+'(9&(1.'2" .J" LMCK>"&'B"

N9CK@P" Y'" .9B+9" (." .M(&1'" &" 0..B" J1(" (." (-+" )+&2%9+B" B&(&" .'" 5KC<N9CK@!" 1'" 9+0&9B" (." (-+" (+)6+9&(%9+"

B+6+'B+',+".J",9++6"9&(+!"A+"J.%'B"1("'+,+22&9G"(.")&:+"(-+",.+JJ1,1+'("1'"(-+"L&M&99.<O+991'0"J.9)%/&" (+)6+9&(%9+"B+6+'B+'(P"

"

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

69.M/+)2!"(-+9+"12"&"B+&9(-".J"&,,%9&(+"&'B"2G2(+)&(1,"B&(&".'",9++6"9&(+"F+92%2"B.6&'(",.',+'(9&(1.'"J.9" (-+"(+)6+9&(%9+"&'B"2(9+22"9&'0+".J"1'(+9+2(P"V+261(+"(-+2+"B9&AM&,:2!".%9",.)6%(&(1.'2"2-.A"(-&(",9++6" 9&(+" 1',9+&2+2" +S6.'+'(1&//G" A1(-" (-+" B.6&'(" ,.',+'(9&(1.'!" .F+9" (-+" 69&,(1,&/" 9&'0+" .J" B.61'0!" A1(-" 2&(12J&,(.9G"&09++)+'("A1(-"+S12(1'0"+S6+91)+'(&/"B&(&P"

"

)

$BCB$BGDB!)

"

31'2,.%0-!"jP"4P!"W10MG!"]P"&'B"D.99.A!"7P"3P"Q#X?#RP"r;JJ+,(".J".SG0+'"6.(+'(1&/".'"(-+"(-+9)&/",9++6".J" '1.M1&<B.6+B"5KC!s"J. Amer. Ceram. Soc.!"I[!"@#><@#?P"

3'B+922.'!"VP"3P!"5M+9%&0&!"4P"8P!"L+91:&9!"8P"fP!"5'&/!"NP"&'B"7(&'+:!"NP"WP"QCH##RP"r5"&'B"t+"(9&'26.9(" 1'"5KC!xh"V+'21(G"J%',(1.'&/"(-+.9G",&/,%/&(1.'2!s"Phys. Rev. B!"?[!"H>[#H>P"

32-MG!" DP" ]P" Q#XIXRP" rK'" 1'(+9J&,+<9+&,(1.'" ,.'(9./" .J" L&M&99.<O+991'0" ,9++6" &'B" 21'(+91'0!s"Scripta Metall.!"@!"?@=<?[CP"

4%9(.'!"4P"Q#X=CRP"rY'(+9J&,+"9+&,(1.'",.'(9.//+B"B1JJ%21.'&/",9++6!s"Mater. Sci. Eng.!"#H!"X<#[P"

4%9(.'!"4P"Q#X==RP"Diffusional Creep of Polycrystalline Materials!"*9&'2<*+,-"8%MP!"4&G"f1//&0+!"K-1.P" V%0&G!" NP!" D.,+//1'!" 3P" V+-&%B(!" 8P" &'B" 7/&B:.JJ!" DP" Q#XXIRP" rO10-" (+)6+9&(%9+" )+,-&'1,&/" (+2(2"

6+9J.9)+B".'"B.6+B"J%+/2!s"Proc., Advances in Fuel Pellet Technology for Improved Performance!s" *.:G.!"j&6&'!"L.F+)M+9"#XXI!"8%M/12-+B"MG"Y3;3!"f1+''&!"3%2(91&!"#XX?P"

]9+G22!" DP!" 8+(1(!" *P" &'B" N9.,.)M+((+!" j<8P" QCHH>R" r8.1'(" B+J+,(2" 1'" %9&'1%)" B1.S1B+h" 3M" 1'1(1." 62+%B.6.(+'(1&/"&669.&,-"1'"(-+"0+'+9&/1U+B"09&B1+'("&669.S1)&(1.'!s"J. Nucl. Mater.!"@[=!"[[<>#P" ]9.2(!"OP"jP"&'B"32-MG!"DP"]P"Q#X?CRP"Deformation-Mechanism Maps!"8+90&).'"89+22!"KSJ.9B!"5^P" i%6(&!" ]P!" 491//&'(!" iP" " &'B" 8&2(%9+/" 3P" QCHH=R" rN.99+/&(1.'" +JJ+,(2" &'B" +'+90+(1,2" .J" 6.1'(" B+J+,(2" 1'"

%9&'1%)"B1.S1B+h"3"J192("691',16/+"1'F+2(10&(1.'!s"Philos. MagP!"?=!"C>I#<C>IXP"

O&A:1'2!" WP" jP" &'B" 3/,.,:!" NP" 4P" Q#XI?RP" r3" 2(%BG" .J" ,&(1.'" B1JJ%21.'" 1'" 5KC_S" &'B" *-KC"%21'0" u<9&G"

26+,(9.)+(9G!s"J. Nucl. Mater.!"CI!"##C<#CCP"

O&G+2!"cP"&'B"7(.'+-&)!"3P"DP"Q#X?>RP"Defects and Defect Processes in Nonmetallic Solids!"j.-'"c1/+G" v"7.'2!"L+A"w.9:!"573"QV.F+9"9+691'("CHH[RP"

O.A/!" VP" 3P!" 8&/)+9!" YP" VP" &'B" *.6/122!" YP" WP" Q#XX[RP" rL1.M1&<B.6+B" J%+/" &2" &" 8NY" 9+)+BG!"Proc.,

International Topical Meeting on Light Water Reactor Fuel Performance!" c+2(" 8&/)" 4+&,-!"

]/.91B&!"3691/"#XX[!"3)+91,&'"L%,/+&9"7.,1+(G!"a&09&'0+"8&9:P"Ya!"573P"

j&,:2.'!"WP"3P!"N&(/.A!"NP"WP"3P"&'B"D%99&G!"3P"VP"Q#X?=RP"r8.1'(<B+J+,(",&/,%/&(1.'2".'"5KC!s"J. Chem. Soc. Faraday Trans. 2!"?@!"##=#<##=IP"

^1)!"^P"NP"&'B"K/&'B+9!"VP"WP"Q#X?#RP"rKSG0+'"B1JJ%21.'"1'"5KC<S!s"J. Nucl. Mater.!"#HC!"#XC<#XXP"

^'.99!"VP"4P!"N&''.'!"WP"DP"&'B"N.M/+!"WP"aP"Q#X?XRP"r3'"&'&/G212".J"B1JJ%21.'"&'B"B1JJ%21.'&/",9++6"1'" 2(.1,-1.)+(91,"&'B"-G6+92(.1,-1.)+(91,"%9&'1%)"B1.S1B+!s"Acta Metall.!"@=!"C#H@<C#C@P"

a1B1&9B!"3P"4P!"Q#XIIRP"r7+/J<B1JJ%21.'".J"%9&'1%)"1'"5KC!s"J. Nucl. Mater.!"#X!"#HI<#H?P"

a1%!"tP"wP!""3'B+922.'!"VP"3P"&'B"5M+9%&0&!"4P"8P"QCH#CRP"r]192(<691',16/+"V]*").B+/1'0".J"'%,/+&9"J%+/" )&(+91&/2!s"J. Mater. Sci.!"[=!"=@I=<=@?[P"

D&92-!"iP!"c..B!"iP"3P"&'B"8+9:1'2!"NP"8P"Q#XXIRP"rL1.M1&<B.6+B"5KC"J%+/")&'%J&,(%91'0"+S6+91+',+"&("

491(12-"L%,/+&9"]%+/2"a(B!s"Proc.,Advances in Fuel Pellet Technology for Improved Performance!s"

*.:G.!"j&6&'!"L.F+)M+9"#XXI!"8%M/12-+B"MG"Y3;3!"f1+''&!"3%2(91&!"#XX?P"

D&221-!"3P"WP"QCH#[RP"r;JJ+,(2".J"&BB1(1F+2".'"%9&'1%)"B1.S1B+"J%+/"M+-&F1.9!s"Swedish Radiation Safety

Authority Report!"CH#[hC#!"7(.,:-./)!"7A+B+'P"

D&221-!"3P"WP"QCH#>RP"r;JJ+,(".J"&BB1(1F+2".'"2+/J<B1JJ%21.'"&'B",9++6".J"5KC"!s"Unpublished."

D&(U:+!"OP"Q#XIXRP"rK'"%9&'1%)"2+/J<B1JJ%21.'"1'"5KC"&'B"5KC_S"!"J. Nucl. Mater.!"@H!"#I<C>P"

D&(U:+!" OP" Q#X?=RP" r3(.)1," (9&'26.9(" 69.6+9(1+2" 1'" 5KC" &'B" )1S+B" .S1B+2" Q5!8%RKC!s"J. Chem. Soc. Faraday Trans.!"?@!"##C#<##[CP"

L+91:&9!"8P!"c&(&'&M+!"*P!"*%/+':.!"jP"7P!"8-1//6.(!"7P"*P"&'B"71''.((!"7P"4P"QCHHXR"r;'+90+(1,2".J"1'(91'21," 6.1'("B+J+,(2"1'"%9&'1%)"B1.S1B+"J9.)"+/+,(9.'1,<2(9%,(%9+",&/,%/&(1.'!s"J. Nucl. Mater.!"@?[!"I#<IXP" L.'.'!"NP!"D+'&9B!"j<NP!"a&'21&9(!"7P"+("&/P"QCHH[RP"8NY"M+-&F1.%9".J",-9.)1%)".S1B+<B.6+B"J%+/, Proc.,

Pellet-clad Interaction in Water Reactor Fuels!s"31S<+'<89.F+',+!"]9&',+!"D&9,-"CHH[P"

W&BJ.9B!"^PNP"Q#X?@RP"r5KC"J%+/"6+//+(")1,9.2(9%,(%9+").B1J1,&(1.'"(-9.%0-"1)6%91(G"&BB1(1.'2!s"J. Nucl. Mater.!"##I!"@H><@#@P"