- Email: [email protected]
High temperature gaseous and molten salt corrosion
High temperature corrOSIon K Natesan-
rnr\1nn~
Q:as~eOllS
and molten salt
National Laboratory, USA
7.1 Introduction
7.2 Corrosion in single oxidant environments
C011slcleralbie research on the causes, corrosion bas been kinetics that n'U\lI",h,,,,,
such as 113
Em.!ineeril1fg Casebook
114
MO the oxygen
pressure
for the MIMO eQUlllbrlUill
e
at
atMIMO
In 5v.lJlv~
(.ILl,
element or>T"n,nc, in an
IS
by
as such as time and reactant in the exposure en'V1f(mnlentt. An enormous amount of literature exists on nucleation scales
temperature gaseous and molten salt corrosion
Temperature (Oe)
I Standard free energy of formation of metal oxides as a function
1327
Temperature (oe)
Standard free energy of formation of metal carbides as a function
115
116
127
7,3 Standard
7.3 Thermodynamic
327
527
727
927
1127 1327
energy of formation of metal nitrides as a function
of reaction in mixed oxidants
1tpT'~tnJP
detjermme gas COl1(}POSltliOns energy for the S, 0 and the total pressure ~n~:lhl'!;!PC have been used to establIsh gaSlmc~tal
mt~eraiCtl()nS
proc:edure:s to muumum free
~t"'flV11r\l in the in mixed gas attlrtos:phleres, it
temperature gaseous and molten salt corrosion
117
mO:leCluar gas snelCtes
OY'JfTp.n/<':llllnhnr
en'V'lr()DDleI1lt, on POSislble on a
[7.6} where AO and AS are <::!ulnhllT
are defined
e
RT
e
+
If we assume unit
2
10 can be reduced to
tlI'Tl'111"'1.1
e hxalIDlflatl()D of
I
[7.11 ]
7.8 and 7.11 oenmts the IQeJtlt111cal:lOn of various
118
situations that
corrOSIon
nl"A.I1UI''tl:!
that can be ">J"JlU..,'...." as
both AO and AS should be
11 mallcat4es
a.
This condition will cause reaction to nroicee~a is in contact
stahle
b.
will be the
and molten salt corrosion
log
(Pa)
7.4 Thermochemical dla~~anls for M-S-O systems at 875"C M Fe,
119
120
UQ.
-11
-7
Log
7.5 Thermochemical
for Cr-C-O systems at 982°C.
7.4 Scaling of alloys i.n bioxidant atmospheres
7.4.1 Behaviour ojCrzOrjormin6 aUoys
temperature gaseous and molten salt corrosion
121
Log pO;? (Pa)
7.6 UX'va:e:nlsulDhurthermochemical for type 310 stainless steel at 727, 927 and 1127 environments calculated for several coal processes.
122
-25
-20
10
15
Log p02 (Pa)
Oxvilf:nlsulnhurthermochemical d1a~uanlS
to chromium oxide/chromium Sul)lhl(le the
e.Cluil1bllU1Jn~
for IN 671 at 727, 927 and several coal gas.lllcatlClfl processes. n~Sl}iectJlveJ[y
ratio on the scale thlclIDe:ss and h exposure, at ten[}pt7alturc~s to gas mixtures with a range nt ()xv:llen pressures. Results from these tests also indicate the "transition" or "kinetic" isata pOz»
temperature
salt corrosion
123
0
-2
boundary
,
,0
~
-4
N
(fJ
Q.
g>
...J
I
-6
I
I
I
Cr:z03
• 0
0
ALLOY
-8
I
I
I
1oc$bo
-20
Cr/Fe SULPHIDE SULPHIDE/OXIDE OXIDE
TYPE 310 SS (875°C)
15
log p02 (Pa)
7.8
7.4.2
On the
develoloed on 310 stainless steel as a function pressures in gas environment at 875°C.
of corrosion behaviour for high chromium alloys
and
124
stainless steel
s:orne\Nh::I.t.
favour oxide scale formation. The scale but the most differences between the
temperature ga.fJeOU:i and molten salt corrosion
pO:!p02(eq)
7. 10 Variation in scale thickness and as a function of excess oxygen parameter 800 to (\'!nJopn/!::1ulnhnr mixed gas environments.
126
2
:>
3
Threshold pOz for oxide-scale formation pS2 for base metal sulphidation 8ulphidation
1--_ _ _ _ _ _+-_ _-'---...;B;.,;.8;.;.s&-;;....,.metal suI phi dation
Kinetic boundary
7.11 Schematic
corrosion resistance.
of material behaviour.
temperature gaseous and molten salt corrosion
I
II III
IV
127
Competition
& internal sulphidation is molten at test tenlperatlJre, outer scale after COOling
oxides and Cr boundarY attack by the
7.12 Schematic reaction sequence for corrosion
w
in
3.
Exposure time (h)
7. 13 Compan!son or1:helrIn()grlivune1:nc test data for several nX'vaf~nhmh'}h1]lr mixed gas.
tested at 871 "C in
128
(:j'
E
~ g
0.8
c
'mC»
0.4
:E
,2> Q)
3t
Exposure time (h) Test temperature 87100
7, 14 A COl1lpafJlSOn
7.4.3 Behaviour ofAl10] alloys
n ..r~n""ri
tenloe:rature corrosion, .. \x.,hp'rph,v either AI or may be mobile, Based on bulk self diffusion scale formation be to exceed the rate of ,.CI
temperature gaseous and molten salt corrosion
7. 15 electron mlc:rOS>COJ>V pJnot!01iU'aptls side of scale/metal interface on
129
130
7. 16 electron at different of scale and metal sides of scale/metal interface on Fe25Cr20Ni3Zr after exposure to low oxygen, environment.
reSllstaJllce is Ol>ta:mc:~
temperature gaseous and molten salt corrosion
131
amooot of
scales grown in sulphurwhich amlostm~res,iliewmmJnJurrl-ccmmmm~
7.4.4 Behaviour o/SiOt/orming alloys
7. 4. 5 Breakdown
environments
132
• • • •
•
Nucleation and sutlSe(IUell1t
eXlJlOse:d to mixed gas atrrloslphe:res second reactant in the gas scales can be
temperature gaseous and molten salt corro~jon
133
clUlmgces in an
1) Particles of Cr appear on the surface of the oxide scale.
grow into islands of richer in Fe.
3)
7.17 o","r~ertlsuIDhllr
mixed
Zr
in
134
Fe 25Cr20Ni Preoxidised for 72 h in tI"' ..... rii.Qoori in - 4 x 10-3 Pa for preoXl,d:ls~~d: in low atrrlOSI)here for different times at
7. 18 MorphllloftPcal atrrlOSl)helre and SUblSeQllently
sut>str'ate O,U, mdllc~ltUJlg some a 7h exposure, the continuous oxide scale has been OreaCtllea~ SUl]pnt,aallon at the substrate/oxide interface is noted. The "'uJ,IJuu• Plirtl(;les to increased sulphur pe11et1eatlon. After u ...,,,......
.l....
temperature
salt corrosion
Internal oxidation in
7.19 Morphc)lo~;tcaj
800
sp~:;;lm4~n
after 500 h
135
136
corrosion .
.... "" ...""'" 7.20 and 7.21
DOlmaam~s aC(~epltal:l e
in
to
lifetimes for high Cr
temperature gaseous and molten salt corrosion
Ga.
Sulfide
Sa.e Meta' Sulfide
(a)
Gas
(d) Oxide
Alloy (b)
le)
Gas Oxide Sulfide
S Channel (1)
(c)
Table 7.1 Bubble
AbOJ
Al:z03
SiOl Fel 03
Cao
Alkalis Other
chemical COJ1rlPOsltU)n Castables Deuse AJ20 J
SiC
Alloy
Gas
Sulfide
of candidate refractories
Fused cast
SiC
137
138 G ••
Ga,
(b)
Sulfide
grain boundary sulfides
represent:aticm of reaction sequences for cnr'OmllR-][Onrnm!!l environments cOllltauung
alumurJUllm sI.llpl111de
n<:lirh£>I,o.C'
interface.
in the
in
7.S Gaseous corrosion of
The fonns of gaseous reaction of
"1£"1ntlrU
materials
materials include reactions
tem'ner'ature gaseous and molten salt corrosion
139
7.6 Deposit-induced corrosion
Corrosion in the presence materials selection and in their a(1(;:Qwacv ot ,)entOf1tnaltlCe
a concern in in several of
140 Gas temperature OC
152 377 Phosphorus pentoxide·rich slags
,Sodium
Alkali iron trisulphates
Alkali sul~lhabas I
Boilersieam generation tubes
..
.. 127
327
572
727
927
Metal temperature (OC) Ke~~m~es
of fireside corrosion
coal-fired boilers.
7. 6.1 Corrosion due to deposits containing alkali, sulphur and oxygen
tubes but may not be a cause Because boiler tube matefllals
TrlCkht',",
of
temperature Direction
7.23
salt corrosion
J41
flow
structure on sUDerbeatc~r
tubes in nulverlsec1-ccJal··bUlmU1IQ boilers.
Intcludmlg sulphur, chlorine in air level used in the combustion process, and metal tel1[1P€~ra1turc~. LUi""'\-"'''';>,
excess detefl1[1me the
142
Temperature
1.24
7.6.2 Corrosion in
environments.
to coal-fired boiler
temperature gaseous and molten salt corro,vion
5
F---~----~~------~~
15 Cr
-25
-45
5
10 Cr -20~------~~----~~~--~------~~
- 35
-25
977 and of various oxide and Phase fields system are also shown.
143
144
to oxygen and
<:!nl'ntuIT
pressures
Qlctatl.:~Q
Mixture 1 CaS
Mixture
2
Mixture 3
:Spc~ClJneJ1S
these
coated with mixtures 1, whereas the
and 4 exhibited coated with mixture 3 still
attack in a
salt corrosion
145
x
146
K
can be used to calculate chromium actIVlty/con,~enltratlOn level of carbide
in the austenite
up to
salt corrosion
carburized to gas mixtures with
7.28 MOltl)hclloglleS 800 spe<~imen!l
7.6.3 Corrosion in
nrll'C'bJ'IPb
147
of alkali slIJphates
matenlals in the presence of sodium sulph~ite, in cOInb1uatlon with sodium has been a Df(}bllem in gas turbmles: this corrosion process "hot corrosion" to dltten~nt1ate gas corrosion have been
148 100r---------------------------------~
Without bed deposit
•
II
IJ
h
1000h 1980h
Corrosion peIiletr;atlo,n presence
sullphldatlOn by inward diffusion of Qnl'nhl1r rates. Extensive of 1 hot corrosion have been pulolH;hed f'nl .....n<'U1' ....
also known as "low tp.1Irln"~rl1t1J'I'·p.hot
oa:se-mt:lat sullphaltes and sodium
tenloeratlures.
e~iPeC::lalIY
corrosion'~
1Tnl,n""p'Q
and occurs in the eftluent of the FBC
temperature
salt
149
Table 7.2 Process environments and modes of material Process! component Pulverised coal boilers Fluidised bed combustion Gasification
Gas enviroument
Gas
Deposit type
Oxidising
1227-1527
377-727
Oxidising locally reducing Reducing sulphur
827-1027
377-927
Ash CaS04, CaO Carbon
927-1127
377-677
Fly ash
Alkali sulphates
Chlorides
Magneto hydro dynamics Gas turbines
777-927
Alkalis Alkali sulphates Chlorides Cock
827-927
Nitric acid production
Oxidising
Refinery plant
Oxidising
Municipal waste incmeration Pulp and paper
Oxidising Oxidising spent liquor
727-827
Heat treating
Oxidising
927-1327
727-927
Chlorides Sulphates
mtriding Aluminium remelting
Oxidising
Fibreglass
Oxidising
oxides
827-1027
Carbonates
Carbon
Halides
Mode of degradation Alkali corrosion
Alkali corrosion Fouling Hot corrosion Erosion
Carburisation Oxidation Oxidation Carburisation Nitridation Oxidation Acid dew point Oxidation Chlorination Stress corrosion Molten salt attack Oxidation Metal Thenual Salt attack Oxidation Chlorination Glass attack
150
7.7 Service environments of interest
7.8 Summary
References
L
2. 3.
temperature gaseous and molten salt corrosion
151
4. 5.
1980.
6.
7. 8.
9.
II. 12. 13.
FE-90/2.
14. 15.
17.
UX:ydeSCl1eC111en auf
Melall,"Q .., 53, 18. Pivin J C et al. "Oxidation Mechanism of t'e--I'Il--Lt'-L.:,)Llr-:,).AI Influence Small Amounts
152
20.
21. 22.
23.
24.
25.
26. 27.
Ceram.
UeltJoslts", American
t"4;;!,f>V14F>r
28.
29.
30. 31. 32.
33. Natesan Bed Combustion AppJl(;attons,".
1990. 34. Natesan K and Podolski W "Materials for FBC COlB:enera1tlon ;::)v~;terns· on Heat Re~~ist,ant f\AEJ·to~JrEJ/f.· 23-26 Sel)!temtber Proc. first Int.
New
temperature
eds, K Natesan 35. 36.
37.
1991.
1Vlarenru ~cu!nc(~",
and molten salt {Y)YI'o.'i:IIJn
153
ASM Internat:lOmlJ, 7,
R A HU~~g1l1IS,
Hot Corrosion
rnr\1nn~
Q:as~eOllS
and molten salt
National Laboratory, USA
7.1 Introduction
7.2 Corrosion in single oxidant environments
C011slcleralbie research on the causes, corrosion bas been kinetics that n'U\lI",h,,,,,
such as 113
Em.!ineeril1fg Casebook
114
MO the oxygen
pressure
for the MIMO eQUlllbrlUill
e
at
atMIMO
In 5v.lJlv~
(.ILl,
element or>T"n,nc, in an
IS
by
as such as time and reactant in the exposure en'V1f(mnlentt. An enormous amount of literature exists on nucleation scales
temperature gaseous and molten salt corrosion
Temperature (Oe)
I Standard free energy of formation of metal oxides as a function
1327
Temperature (oe)
Standard free energy of formation of metal carbides as a function
115
116
127
7,3 Standard
7.3 Thermodynamic
327
527
727
927
1127 1327
energy of formation of metal nitrides as a function
of reaction in mixed oxidants
1tpT'~tnJP
detjermme gas COl1(}POSltliOns energy for the S, 0 and the total pressure ~n~:lhl'!;!PC have been used to establIsh gaSlmc~tal
mt~eraiCtl()nS
proc:edure:s to muumum free
~t"'flV11r\l in the in mixed gas attlrtos:phleres, it
temperature gaseous and molten salt corrosion
117
mO:leCluar gas snelCtes
OY'JfTp.n/<':llllnhnr
en'V'lr()DDleI1lt, on POSislble on a
[7.6} where AO and AS are <::!ulnhllT
are defined
e
RT
e
+
If we assume unit
2
10 can be reduced to
tlI'Tl'111"'1.1
e hxalIDlflatl()D of
I
[7.11 ]
7.8 and 7.11 oenmts the IQeJtlt111cal:lOn of various
118
situations that
corrOSIon
nl"A.I1UI''tl:!
that can be ">J"JlU..,'...." as
both AO and AS should be
11 mallcat4es
a.
This condition will cause reaction to nroicee~a is in contact
stahle
b.
will be the
and molten salt corrosion
log
(Pa)
7.4 Thermochemical dla~~anls for M-S-O systems at 875"C M Fe,
119
120
UQ.
-11
-7
Log
7.5 Thermochemical
for Cr-C-O systems at 982°C.
7.4 Scaling of alloys i.n bioxidant atmospheres
7.4.1 Behaviour ojCrzOrjormin6 aUoys
temperature gaseous and molten salt corrosion
121
Log pO;? (Pa)
7.6 UX'va:e:nlsulDhurthermochemical for type 310 stainless steel at 727, 927 and 1127 environments calculated for several coal processes.
122
-25
-20
10
15
Log p02 (Pa)
Oxvilf:nlsulnhurthermochemical d1a~uanlS
to chromium oxide/chromium Sul)lhl(le the
e.Cluil1bllU1Jn~
for IN 671 at 727, 927 and several coal gas.lllcatlClfl processes. n~Sl}iectJlveJ[y
ratio on the scale thlclIDe:ss and h exposure, at ten[}pt7alturc~s to gas mixtures with a range nt ()xv:llen pressures. Results from these tests also indicate the "transition" or "kinetic" isata pOz»
temperature
salt corrosion
123
0
-2
boundary
,
,0
~
-4
N
(fJ
Q.
g>
...J
I
-6
I
I
I
Cr:z03
• 0
0
ALLOY
-8
I
I
I
1oc$bo
-20
Cr/Fe SULPHIDE SULPHIDE/OXIDE OXIDE
TYPE 310 SS (875°C)
15
log p02 (Pa)
7.8
7.4.2
On the
develoloed on 310 stainless steel as a function pressures in gas environment at 875°C.
of corrosion behaviour for high chromium alloys
and
124
stainless steel
s:orne\Nh::I.t.
favour oxide scale formation. The scale but the most differences between the
temperature ga.fJeOU:i and molten salt corrosion
pO:!p02(eq)
7. 10 Variation in scale thickness and as a function of excess oxygen parameter 800 to (\'!nJopn/!::1ulnhnr mixed gas environments.
126
2
:>
3
Threshold pOz for oxide-scale formation pS2 for base metal sulphidation 8ulphidation
1--_ _ _ _ _ _+-_ _-'---...;B;.,;.8;.;.s&-;;....,.metal suI phi dation
Kinetic boundary
7.11 Schematic
corrosion resistance.
of material behaviour.
temperature gaseous and molten salt corrosion
I
II III
IV
127
Competition
& internal sulphidation is molten at test tenlperatlJre, outer scale after COOling
oxides and Cr boundarY attack by the
7.12 Schematic reaction sequence for corrosion
w
in
3.
Exposure time (h)
7. 13 Compan!son or1:helrIn()grlivune1:nc test data for several nX'vaf~nhmh'}h1]lr mixed gas.
tested at 871 "C in
128
(:j'
E
~ g
0.8
c
'mC»
0.4
:E
,2> Q)
3t
Exposure time (h) Test temperature 87100
7, 14 A COl1lpafJlSOn
7.4.3 Behaviour ofAl10] alloys
n ..r~n""ri
tenloe:rature corrosion, .. \x.,hp'rph,v either AI or may be mobile, Based on bulk self diffusion scale formation be to exceed the rate of ,.CI
temperature gaseous and molten salt corrosion
7. 15 electron mlc:rOS>COJ>V pJnot!01iU'aptls side of scale/metal interface on
129
130
7. 16 electron at different of scale and metal sides of scale/metal interface on Fe25Cr20Ni3Zr after exposure to low oxygen, environment.
reSllstaJllce is Ol>ta:mc:~
temperature gaseous and molten salt corrosion
131
amooot of
scales grown in sulphurwhich amlostm~res,iliewmmJnJurrl-ccmmmm~
7.4.4 Behaviour o/SiOt/orming alloys
7. 4. 5 Breakdown
environments
132
• • • •
•
Nucleation and sutlSe(IUell1t
eXlJlOse:d to mixed gas atrrloslphe:res second reactant in the gas scales can be
temperature gaseous and molten salt corro~jon
133
clUlmgces in an
1) Particles of Cr appear on the surface of the oxide scale.
grow into islands of richer in Fe.
3)
7.17 o","r~ertlsuIDhllr
mixed
Zr
in
134
Fe 25Cr20Ni Preoxidised for 72 h in tI"' ..... rii.Qoori in - 4 x 10-3 Pa for preoXl,d:ls~~d: in low atrrlOSI)here for different times at
7. 18 MorphllloftPcal atrrlOSl)helre and SUblSeQllently
sut>str'ate O,U, mdllc~ltUJlg some a 7h exposure, the continuous oxide scale has been OreaCtllea~ SUl]pnt,aallon at the substrate/oxide interface is noted. The "'uJ,IJuu• Plirtl(;les to increased sulphur pe11et1eatlon. After u ...,,,......
.l....
temperature
salt corrosion
Internal oxidation in
7.19 Morphc)lo~;tcaj
800
sp~:;;lm4~n
after 500 h
135
136
corrosion .
.... "" ...""'" 7.20 and 7.21
DOlmaam~s aC(~epltal:l e
in
to
lifetimes for high Cr
temperature gaseous and molten salt corrosion
Ga.
Sulfide
Sa.e Meta' Sulfide
(a)
Gas
(d) Oxide
Alloy (b)
le)
Gas Oxide Sulfide
S Channel (1)
(c)
Table 7.1 Bubble
AbOJ
Al:z03
SiOl Fel 03
Cao
Alkalis Other
chemical COJ1rlPOsltU)n Castables Deuse AJ20 J
SiC
Alloy
Gas
Sulfide
of candidate refractories
Fused cast
SiC
137
138 G ••
Ga,
(b)
Sulfide
grain boundary sulfides
represent:aticm of reaction sequences for cnr'OmllR-][Onrnm!!l environments cOllltauung
alumurJUllm sI.llpl111de
n<:lirh£>I,o.C'
interface.
in the
in
7.S Gaseous corrosion of
The fonns of gaseous reaction of
"1£"1ntlrU
materials
materials include reactions
tem'ner'ature gaseous and molten salt corrosion
139
7.6 Deposit-induced corrosion
Corrosion in the presence materials selection and in their a(1(;:Qwacv ot ,)entOf1tnaltlCe
a concern in in several of
140 Gas temperature OC
152 377 Phosphorus pentoxide·rich slags
,Sodium
Alkali iron trisulphates
Alkali sul~lhabas I
Boilersieam generation tubes
..
.. 127
327
572
727
927
Metal temperature (OC) Ke~~m~es
of fireside corrosion
coal-fired boilers.
7. 6.1 Corrosion due to deposits containing alkali, sulphur and oxygen
tubes but may not be a cause Because boiler tube matefllals
TrlCkht',",
of
temperature Direction
7.23
salt corrosion
J41
flow
structure on sUDerbeatc~r
tubes in nulverlsec1-ccJal··bUlmU1IQ boilers.
Intcludmlg sulphur, chlorine in air level used in the combustion process, and metal tel1[1P€~ra1turc~. LUi""'\-"'''';>,
excess detefl1[1me the
142
Temperature
1.24
7.6.2 Corrosion in
environments.
to coal-fired boiler
temperature gaseous and molten salt corro,vion
5
F---~----~~------~~
15 Cr
-25
-45
5
10 Cr -20~------~~----~~~--~------~~
- 35
-25
977 and of various oxide and Phase fields system are also shown.
143
144
to oxygen and
<:!nl'ntuIT
pressures
Qlctatl.:~Q
Mixture 1 CaS
Mixture
2
Mixture 3
:Spc~ClJneJ1S
these
coated with mixtures 1, whereas the
and 4 exhibited coated with mixture 3 still
attack in a
salt corrosion
145
x
146
K
can be used to calculate chromium actIVlty/con,~enltratlOn level of carbide
in the austenite
up to
salt corrosion
carburized to gas mixtures with
7.28 MOltl)hclloglleS 800 spe<~imen!l
7.6.3 Corrosion in
nrll'C'bJ'IPb
147
of alkali slIJphates
matenlals in the presence of sodium sulph~ite, in cOInb1uatlon with sodium has been a Df(}bllem in gas turbmles: this corrosion process "hot corrosion" to dltten~nt1ate gas corrosion have been
148 100r---------------------------------~
Without bed deposit
•
II
IJ
h
1000h 1980h
Corrosion peIiletr;atlo,n presence
sullphldatlOn by inward diffusion of Qnl'nhl1r rates. Extensive of 1 hot corrosion have been pulolH;hed f'nl .....n<'U1' ....
also known as "low tp.1Irln"~rl1t1J'I'·p.hot
oa:se-mt:lat sullphaltes and sodium
tenloeratlures.
e~iPeC::lalIY
corrosion'~
1Tnl,n""p'Q
and occurs in the eftluent of the FBC
temperature
salt
149
Table 7.2 Process environments and modes of material Process! component Pulverised coal boilers Fluidised bed combustion Gasification
Gas enviroument
Gas
Deposit type
Oxidising
1227-1527
377-727
Oxidising locally reducing Reducing sulphur
827-1027
377-927
Ash CaS04, CaO Carbon
927-1127
377-677
Fly ash
Alkali sulphates
Chlorides
Magneto hydro dynamics Gas turbines
777-927
Alkalis Alkali sulphates Chlorides Cock
827-927
Nitric acid production
Oxidising
Refinery plant
Oxidising
Municipal waste incmeration Pulp and paper
Oxidising Oxidising spent liquor
727-827
Heat treating
Oxidising
927-1327
727-927
Chlorides Sulphates
mtriding Aluminium remelting
Oxidising
Fibreglass
Oxidising
oxides
827-1027
Carbonates
Carbon
Halides
Mode of degradation Alkali corrosion
Alkali corrosion Fouling Hot corrosion Erosion
Carburisation Oxidation Oxidation Carburisation Nitridation Oxidation Acid dew point Oxidation Chlorination Stress corrosion Molten salt attack Oxidation Metal Thenual Salt attack Oxidation Chlorination Glass attack
150
7.7 Service environments of interest
7.8 Summary
References
L
2. 3.
temperature gaseous and molten salt corrosion
151
4. 5.
1980.
6.
7. 8.
9.
II. 12. 13.
FE-90/2.
14. 15.
17.
UX:ydeSCl1eC111en auf
Melall,"Q .., 53, 18. Pivin J C et al. "Oxidation Mechanism of t'e--I'Il--Lt'-L.:,)Llr-:,).AI Influence Small Amounts
152
20.
21. 22.
23.
24.
25.
26. 27.
Ceram.
UeltJoslts", American
t"4;;!,f>V14F>r
28.
29.
30. 31. 32.
33. Natesan Bed Combustion AppJl(;attons,".
1990. 34. Natesan K and Podolski W "Materials for FBC COlB:enera1tlon ;::)v~;terns· on Heat Re~~ist,ant f\AEJ·to~JrEJ/f.· 23-26 Sel)!temtber Proc. first Int.
New
temperature
eds, K Natesan 35. 36.
37.
1991.
1Vlarenru ~cu!nc(~",
and molten salt {Y)YI'o.'i:IIJn
153
ASM Internat:lOmlJ, 7,
R A HU~~g1l1IS,
Hot Corrosion