Post on 08-Oct-2020
17th International Symposium on Zirconium in the Nuclear Industry
The effect of Sn on corrosion mechanisms i d d Z l ddi f PWRin advanced Zr-cladding for PWR
Philipp Frankel, J. Wei, E. Francis, S. Lyon, R.A. Cottis, M. PreussMaterials Performance Centre, The University of Manchester
N Ni S L P C R M GN. Ni, S. Lozano-Perez, C. R. M. GrovenorDepartment of Materials, University of Oxford
R. J. Comstock, L. HallstadiusWestinghouse, USA/SwedenA. Ambard, M. Blat-Yrieix
EDF FranceEDF, France
03-08 February, Hyderabad, India
Oxi
datio
n of
Zr
Allo
ysyWhat w
e know
:
Large compressive stress in oxide
gp
Zr to
ZrO
2transformation ‐volum
e increase
Tw
ooxideph
ases:M
onoclinic,Tetragonal
Two oxide ph
ases: M
onoclinic, Tetragonal
Tetragon
al only stable at 3
60C by stress, grain size (or chem
istry)
Transformation Tet
mon
o, fu
rthe
r volume increase
Gll
Tlh
if
Gen
erally, m
ore Tetragon
al phase near interface
Recent work (M
UZIC program):
Level of transform
ation im
portant to transitio
n
Related to nano‐po
rosity in
oxide
1A
STM
Intl,
Vol
. 8, N
o. 9
, doi
: 10:
1520
/JA
I103
246,
201
1, 6
49-6
812
Jour
nal o
f Nuc
lear
Mat
eria
ls 4
32 (2
013)
, pp.
102
-112
3ActaMateralia, 2013
The
effe
ct o
f Sn:
Del
ayed
tran
sitio
ny
ZIR
LO®
Exp
erim
enta
l Z
IRLO
®E
xper
imen
tal
allo
y
~0.
92 w
t% S
n~
0.01
wt%
Sn
0.92
wt%
Sn
Exp
osur
e at
360
C in
Wat
er (
Day
s)E
xpos
ure
at 3
60C
in W
ater
(D
ays)
Tabl
e 1:
Mea
sure
d ch
emic
al c
ompo
sitio
n of
the
mat
eria
ls.
Allo
y Al
loyi
ng E
lem
ents
Zr
Fe
[wt%
] Sn
[wt%
] N
b[w
t%]
Hyd
roge
n [w
t.ppm
] ZI
RLO
®ba
lanc
e0
090
920
9110
p(
y)
ZIR
LO
bala
nce
0.09
0.92
0.91
10
A-0.
0%Sn
ba
lanc
e 0.
1 0.
01
1.00
17
Syn
chro
tron
X-R
ay D
iffra
ctio
ny
y
ZIR
LO®
A0
0%S
n
Evolution of Residual stress and ph
ase fractio
n
ZIR
LO®
A-0
.0%
Sn
Ex-
situ
XR
DE
x-si
tu X
RD
Ex
situ
XR
DE
xsi
tu X
RD
Exp
osur
e at
360
C in
Wat
er (
Day
s)E
xpos
ure
at 3
60C
in W
ater
(D
ays)
p(
y)
Measure sam
ples after different len
gths of autoclave exposure
Syn
chro
tron
XR
D: P
enet
ratio
n de
pth
H
igh-
ener
gy a
nd h
igh
flux
S
uffic
ient
pen
etra
tion
to s
ampl
e en
tire
oxid
e as
oxi
de th
icke
nsp
p
Labo
rato
ry X
RD
Syn
chro
tron
XR
D
Thin
oxi
deM
tl
(~ 3
µm)
Met
al
Thic
ker o
xide
Syn
chro
tron
XR
D:
H
igh-
ener
gy a
nd h
igh
flux
S
uffic
ient
pen
etra
tion
to s
ampl
e en
tire
oxid
e as
oxi
de th
icke
nsp
p
Fast
cou
ntin
g tim
es
G
ood
sign
al, l
ow b
ackg
roun
dP
hf
ti
Pha
se fr
actio
n
Res
idua
l Stre
ss M
onoc
linic
& T
etra
gona
l pha
ses
Syn
chro
tron
XR
D R
esul
ts: E
ffect
of S
ny
Te
trago
nal P
hase
Fra
ctio
n
ZIR
LOA
-0.0
%S
n
Oxi
deO
idO
xide
Met
alM
etal
Oxi
de
Met
alM
etal
Oxi
de
The
effe
ct o
f Sn:
Res
idua
l stre
ssZ
IRLO
A-0
.0%
Sn
Mon
oclin
ic
Tet
rago
nal
The
effe
ct o
f Sn:
Res
idua
l stre
ssZ
IRLO
A-0
.0%
Sn
Mon
oclin
ic
Not
str
ess
stab
ilise
do
ses
ss
abse
d
Tet
rago
nal
Ex-
situ
syn
chro
tron
XR
DI
id
b
ZIR
LO®
Allo
y
Interesting tren
ds, but…
ZIR
LO®
Allo
y A
Ex-
situ
XR
DE
x-si
tu X
RD
Ex
situ
XR
DE
xsi
tu X
RD
Exp
osur
e at
360
C in
Wat
er (
Day
s)E
xpos
ure
at 3
60C
in W
ater
(D
ays)
p(
y)
Only few points, different sam
ples
relatively high
scatter
No inform
ation from
early in
corrosion
In-S
itu E
xper
imen
t
Sample he
ated
in air at 5
50C during XR
D
Fast eno
ugh grow
th fo
r 12 ho
ur experim
ent
Nid
li
i?
Not ideal com
parison to ex‐situ m
easuremen
ts?
Manydata
pointsfrom
singlepo
into
nsinglesample!
Many data points from
single po
into
n singlesample!
ZIRLO
Hihiii
llh
d
ihi
Tet
rago
nal p
hase
evo
lutio
n at
550
C
ZIRLO: H
igh initial te
tragon
al phase
redu
ces with
time
tion ase fract nal pha Tetrago T
Oxi
datio
n tim
e at
550
C
Tet
rago
nal p
hase
evo
lutio
n at
550
C
Hihiii
llh
d
ihi
Lower te
tragon
al con
tent fo
r A‐0%Sn
High initial te
tragon
al phase
redu
ces with
time
tion ase fract nal pha Tetrago T
Oxi
datio
n tim
e at
550
C
Tet
rago
nal p
hase
evo
lutio
n at
550
C
Plb
df
A0%
S
Plateau ob
served
for A
‐0%Sn
tion ase fract nal pha Tetrago T
Oxi
datio
n tim
e at
550
C
Effe
ct o
f red
uced
Sn
Lower te
t. pha
seA
ihE
ib
if
360C
Agrees with
Ex‐situ observatio
n for 3
60C
Sn
stabilises tetragon
al phase in
engineering
ceram
ics
Plateau with prolon
ged oxidation
Agrees with
Ex‐situ observatio
n for 3
60C
g
Tet. phase uniform
ly distributed
, i.e. not stress stabilised
Hihiitilt
th
didl
High initial tet. p
hase, red
uces ra
pidly
Not observed previously!!!
Tilti
tibl
itTime resolutio
n no
t possible ex‐situ
Mon
oclin
ic r
esid
ual s
tres
s at
550
C
Co
nstant m
onoclinic stress for ZIRLO
Mon
oclin
ic r
esid
ual s
tres
sLower Snalloy –lower stresses that re
lax over time
Re
duced creep strength (impo
rtant b
enefit of Sn!)
pg
(p
)
Mon
oclin
ic r
esid
ual s
tres
sLower Snalloy –lower stresses that re
lax over time
Re
duced creep strength (impo
rtant b
enefit of Sn!)
pg
(p
)
Sh
arp
dro
p in
T
et F
ract
ion
Tet
. Fra
ctio
n
Ph
ase
tran
s?
Tet
rago
nal r
esid
ual s
tres
sg
ZIRLO –large compressive stress, som
e relaxatio
n
Lower te
tpeak intensity
–larger scatter
Re
duced creep strength
Tet
rago
nal r
esid
ual s
tres
sg
A‐0%Sn
–Lower com
pressive stress
Even
lower te
tpeak intensity
–Even
larger scatter!
Tet
rago
nal r
esid
ual s
tres
sg
Stress canno
t be stabilising
mechanism
With
low Sn, only grain size stabilised
tetragon
al present
Not
stressstabilised
Not stress stabilised
Sum
mar
yy
O
bser
vatio
nsat
550
Cco
rrel
ates
wel
lwith
360
CO
bser
vatio
ns a
t 550
C c
orre
late
s w
ell w
ith 3
60C
S
imila
r mec
hani
sm d
espi
te d
iffer
ent e
nviro
nmen
t
R
educ
ed S
n
Low
er te
trago
nal p
hase
frac
tion
N
otst
ress
stab
ilise
d
Not
stre
ss s
tabi
lised
D
elay
ed tr
ansi
tion
with
redu
ced
Sn
R
elat
ed to
lack
of s
tress
sta
bilis
ed T
etra
gona
l
redu
ced
trans
form
atio
n
Pro
pose
d m
odel
Wha
t hap
pens
aro
und
trans
ition
?
Pre
-tra
nsiti
on:
Larg
er T
et g
rain
sLa
rger
Tet
. gra
ins,
Str
ess
stab
ilise
d
Gra
dual
tran
sfor
mat
ion
U
ncon
nect
ed N
ano
poro
sity
Wha
t hap
pens
aro
und
trans
ition
?
Pre
-tra
nsiti
on:
Larg
er T
et g
rain
sT
rans
ition
:R
apid
tran
sfor
mat
ion
Larg
er T
et. g
rain
s,S
tres
s st
abili
sed
Tra
nsfo
rmed
Rap
id tr
ansf
orm
atio
nLo
calis
edin
com
patib
ilitie
s
Lo
wer
str
ess
tr
ansf
orm
atio
n
Vo
lum
e in
crea
se
Gra
dual
tran
sfor
mat
ion
U
ncon
nect
ed N
ano
poro
sity
Wha
t hap
pens
aro
und
trans
ition
?
Pre
-tra
nsiti
on:
Larg
er T
et g
rain
sT
rans
ition
:R
apid
tran
sfor
mat
ion
Larg
er T
et. g
rain
s,S
tres
s st
abili
sed
Tra
nsfo
rmed
Rap
id tr
ansf
orm
atio
nLo
calis
edin
com
patib
ilitie
s
Lo
wer
str
ess
tr
ansf
orm
atio
n
Vo
lum
e in
crea
se
Gra
dual
tran
sfor
mat
ion
U
ncon
nect
ed N
ano
poro
sity
Rap
id tr
ansf
orm
atio
n
Inte
rcon
nect
ed p
oros
ityF
E c
ourt
esy
of P
. Pla
tt
Fur
ther
opt
ions
p
Low
er te
mpe
ratu
re o
xida
tion
S
low
er o
xida
tion
O
xida
tion
in s
team
A
pply
stea
mdu
ring
test
ing
A
pply
ste
am d
urin
g te
stin
g
H
igh
tem
ps. &
Tra
nsie
nts
~
LOC
A co
nditi
ons
Ali
dl
dd
iid
ti
App
lied
load
dur
ing
oxid
atio
n
Effe
ct o
n ox
idat
ion
rate
Ack
now
ledg
men
ts
g
MU
ZIC
par
tner
s:
ED
F, N
atio
nal N
ucle
ar L
abor
ator
y, R
olls
-Roy
ce, A
mec
and
,y,
y,
Wes
tingh
ouse
D
iam
ond
Ligh
t Sou
rce
I12
bli
I1
2 be
am li
ne
Eve
ryon
e th
at h
elpe
d on
Exp
erim
ent!
Fu
ndin
gg
Than
ks to
the
Eng
inee
ring
and
Phy
sica
l Sci
ence
Res
earc
h C
ounc
il (E
PS
RC
) and
MoD
in
the
UK
for f
undi
ng th
e re
sear
ch a
s pa
rt of
the
Mat
eria
ls fo
r Ene
rgy
call
(res
earc
h co
de:
EP
/E03
6171
/1).