The oxidation behaviour of 304 stainless steel in oxygenated hightemperature water

Wenjun Kuang, Xinqiang Wu ⇑, En-Hou HanState Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, 110016 Shenyang, PR China

a r t i c l e i n f o

Article history:Received 20 June 2010Accepted 1 September 2010Available online 7 September 2010

Keywords:A. Stainless steelB. Raman spectroscopyB. XPSB. SEMC. Oxidation

a b s t r a c t

Characteristics of the oxide films formed on 304 stainless steel immersed in 290 �C oxygenated water fordifferent duration time were examined. The results show that the oxide film is mainly composed of outerirregularly shaped a-(Fe, Cr)2O3 and minor spinel in the inner layer. The morphology and chemical com-position of the oxide film evolve with increasing immersion time. The surface layer is first enriched in Crand then enriched in Fe. It is proposed that the oxide nucleated by solid-state reactions with the selectivedissolution of Fe and Ni, and grew up through precipitation of extraneous metallic ions from solution.

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1. Introduction

Type 304 stainless steel (SS) is an important construction mate-rial widely used in the nuclear power industry, which can sufferundesirable degradation after long time service, e.g. the environ-mentally assisted cracking in boiling water reactor (BWR) environ-ments [1]. Although austenitic stainless steels generally showexcellent corrosion resistance in pressurized water reactor (PWR)environments, they are also susceptible to stress corrosion crack-ing (SCC) failures in local occluded volumes where unfavorablyhigh concentration of O2 can accumulate [2].

It is generally accepted that the oxide film formed during ser-vice plays an important role in the performance of material andthe oxidation of austenitic stainless steels in high temperatureand high pressure water has been a subject of interest to manyresearchers. Many researchers [3–5] found that the oxide filmformed on austenitic stainless steels exposed to oxygenated hightemperature water was composed of an outer layer of relativelylarge hematite particles and an inner layer of fine-grained andCr-enriched spinel type magnetite. Up to now, most related workwas focused on the characterization of oxide film after a certainamount of immersion time. But very little work has been done tostudy the oxidation process of related materials and very limitedknowledge was known about how the oxide film evolved withincreasing immersion time.

In the open literature, it was generally accepted that the oxidefilm formed on stainless steels in high temperature water con-

tained more Cr in the inner layer than in the outer layer, no matterthe water was oxygenated, deaerated or hydrogenated [3–10].However, different mechanisms of high temperature aqueous oxi-dization were proposed to rationalize this phenomenon. Severalprevalent models have been reviewed by Stellwag [7]. Robertson[6] thought that because the growth rates of oxides were much fas-ter than diffusion rates of alloying elements in the metals, eachcomponent of the alloy would pass congruently into the oxide filmbefore any preferential diffusion happened and no depletion of theunderlying metal occurred. The location of an alloy componentacross the oxide layer depended on its diffusion rate in the oxide.Faster diffusing impurities will pass through to the outer layer,while slower moving atoms like Cr would be retained and enrichedin the inner layer. Stellwag [7] suggested that the double-layeroxide structure observed on alloy 800 in high temperature watercould be explained by solid state growth of the inner layer and adissolution–precipitation mechanism for the formation of the out-er layer. He also mentioned that the enrichment of Cr in the innerlayer could be explained by preferential dissolution of Fe and Niduring passivation and the low diffusivity and solubility of Cr inthe spinel lattice, but no convincing proof was provided in hiswork. Ziemniak et al. [8] studied the corrosion behaviour of 304stainless steel in 260 �C hydrogenated water and found that themetal composition of corrosion oxide was the same as the metalcomposition of the alloy substrate. Accordingly, they thought thatcorrosion occurred in a non-selective manner and proposed thatthe compositional difference between the two layers was causedby spinel immiscibility. In our previous work [11], it was foundthat the hematite particles formed on 304 stainless steel containedmore Cr in the inner than in the outer part and it was proposed that

0010-938X/$ - see front matter � 2010 Elsevier Ltd. All rights reserved.doi:10.1016/j.corsci.2010.09.001

⇑ Corresponding author. Tel.: +86 24 2384 1883; fax: +86 24 2389 4149.E-mail address: xqwu@imr.ac.cn (X. Wu).

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the oxide particles nucleated first by solid-state reactions with theselective dissolution of Fe and Ni, and then grew by precipitation.So there still exists uncertainty concerning the oxidation mecha-nism of metallic materials in high temperature aqueous environ-ments and more detailed work is needed to clarify it.

The present work investigated the phase structures, morpholo-gies and chemical composition of the oxide films grown on 304stainless steel exposed to 290 �C water containing 3 ppm (byweight) O2 for different duration time, using X-ray diffraction(XRD), Raman spectrum, scanning electron microscopy (SEM) andX-ray photoelectron spectroscopy (XPS). The related corrosionmechanism is also discussed.

2. Experimental

2.1. Apparatus

Exposure experiments in high temperature and high pressurewater were carried out in an autoclave with a water loop. Fig. 1is a schematic diagram of the testing system used in the presentwork, consisting of a high pressure pump, two sets of preheaterand autoclave, a heat exchanger and a back-pressure regulatorvalve. The immersion tests were performed in autoclave 2 whichwas made of 316 stainless steel and had a volume of 2 L. The inletand outlet water chemistry parameters, namely dissolved oxygenconcentration (DO) and conductivity were monitored with MET-TLER TOLEDO Thornton Model 3X7-210 dissolved oxygen sensorsand Model 240-201 conductivity sensors. A computer with Lab-view8.5 software was used to control temperature and DO. Thetemperature fluctuation was well within ±0.5 �C and the DO fluctu-ation in inlet water was within ±10 ppb. This test system has beendescribed in our previous work [11].

2.2. Materials and testing conditions

The chemical composition of the type 304 SS used in the presentwork is listed in Table 1. Specimens were cut from mill annealedplates. They were mechanically abraded with emery paper up to#800 successively and degreased with ethanol before exposuretests. The specimens were immersed in the autoclave for 1, 26,100, 388, 612, 1000 h respectively. The testing conditions are sum-marized in Table 2.

2.3. Methodology

After exposure, the specimens were cleaned and dried. Oxidephase analysis was performed using a D/Max 2400 X-ray diffrac-tion (XRD) analyzer with Cu Ka radiation and a BWS905 customRaman system. The Raman system contains a powerful laser at532 nm with a maximum power of 1.5 W, a deep thermoelectric-cooled back-thinned charge coupled device spectrometer and acustom designed Raman probe which is coupled with spectrometerin free space format. The Raman shift range is 175–2875 cm�1 andthe spectral resolution is 12 cm�1. The integration time used was15 or 20 s depending on the signal intensity of the specimens.The validity of this Raman system was confirmed after many tests.The surface morphology of the specimens was examined by anINSPECT F scanning electron microscopy (SEM). XPS measurementswere performed with ESCALAB250 X-ray photoelectron spectrom-eter. Photoelectron emission was excited by monochromatic Al Kasource operated at 150 W with initial photo energy of 1486.6 eV.The C1s peak from adventitious carbon at 285 eV was used as areference to correct the charging shifts. Depth profiling was per-formed over an area of 2 � 2 mm under 2 keV Ar-ion sputteringand spectra were obtained over a 0.5 mm spot using a focusingX-ray monochromator. Sputtering rate was determined to be about0.2 nm/s with reference to Ta2O5 layer.

3. Results

Fig. 2 shows the XRD patterns of the oxide films formed on type304 SS exposed to 290 �C water containing 3 ppm O2 for differenttime. The positions of characteristic peaks suggest a hematitestructure and are between that for a-Fe2O3 and Cr2O3. So thehematite is non-stoichiometric in composition and could be for-mulated as a-(Fe, Cr)2O3. Weak peaks of spinel are also discernable.It is found that the oxide films are mainly composed of a-(Fe,Cr)2O3 irrespective of the immersion time. The specimens after1 h immersion were only slightly oxidized and the characteristicpeaks can not be detected clearly.

Fig. 3 shows the Raman spectra of the oxide films. The peaks onthe spectra show no obvious change with increasing immersiontime. In order to study the inner oxide, the surfaces of some spec-imens were carefully abraded with #5000 SiC paper to remove theoutermost layer. Fig. 4 shows the Raman spectra of specimens im-mersed for 1000 h before and after abrasion. Hematite structure isresponsible for the Raman peaks at 229, 299, 409, 478, 606, and653 cm�1 and spinel is responsible for the Raman peaks at 215,340, 484, 478, 573, and 693 cm�1 [4,12–15]. It is clear that bothhematite and spinel are detected after abrasion.

Fig. 5 shows the SEM morphologies of the oxide films afterimmersion for different time. Tiny oxide particles were observedafter 1 h immersion (Fig. 5a). The outer particles grew up to a cer-tain size and seemingly ceased to develop and the surface scaleseemed to become more compact with increasing time (Figs. 5b–f and 6 shows the enlarged images of the oxide films after 100and 1000 h immersion. Note that the oxide particles are irregularlyshaped, the sides of particles are rarely straight and the angles aremostly blunt. The size of the oxide particles is inhomogeneous. Thelarge ones are dispersed on the surface with a maximum diameterof about 300 nm and the small ones seem to be subsurface. Withincreasing immersion time, the surface oxide layer seemingly be-came more compact due to the up-growing of subsurface oxideparticles (Fig. 6b).

Fig. 7 shows the XPS spectra of O 1s, Fe 2p3/2, Cr 2p3/2 and Ni2p3/2 for oxide film formed on the specimen after 612 h immer-sion. The main peak in O 1s spectra (Fig. 7a) is at about 530.5 eVwhich is assigned to O2� in M2O3 [16,17]. In Fe 2p3/2 spectraFig. 1. Schematic diagram of the high temperature and high pressure water loop.

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(Fig. 7b), the peak at about 710.6 eV is assigned to Fe3+ [16–18]. Asto Cr 2p3/2 spectra, the peak at about 576.8 eV is assigned to Cr3+

[16–18]. The peak at 853 eV in Ni 2p3/2 spectra is assigned tometallic Ni0 [16–18].

Fig. 8 presents the elemental composition of the surface layer ofoxide films formed on type 304 SS exposed to 290 �C water con-taining 3 ppm O2 for different time. The data for the specimenwithout immersion is also included for comparison purpose, whichis denoted with horizontal dashed lines. In order to remove theoutmost contaminated layer, each specimen was sputtered for30 s before the data was taken. It is apparent that Ni content inthe surface layer of oxide films decreases to a very low level rapidlyafter short-term immersion and then keeps almost constant withincreasing immersion time. Cr is first enriched in the surface layerafter short-term immersion, and then decreases gradually to a lowlevel. On the contrary, Fe is first depleted and then gradually buildsup. The elemental composition of the surface layer of oxide filmsseems to become constant after 100 h immersion.

Fig. 9 shows the XPS depth profile for oxide film on the speci-men after 1 h immersion. The data acquired without sputtering isnot taken into account because of surface contamination. It shouldbe mentioned that the signals after 390 s sputtering are mainlyfrom the matrix. From outer to inner layer, Cr content gradually de-creases to the level similar to the matrix, while Ni content and Fecontent gradually increase to the level similar to the matrix.Fig. 10 shows the XPS depth profile for oxide film on the specimenafter 612 h immersion. With increasing sputtering time, it is foundthat Ni content in the oxide film is very low and keeps almost con-stant, Cr content increases gradually, while Fe content decreases. Itis noteworthy that the trends for Fe and Cr in Fig. 10 are obviouslydifferent from those in Fig. 9.

4. Discussion

The XRD patterns (Fig. 2) and Raman spectra (Fig. 3) in thepresent work suggest that the oxide films formed on type 304 SS

Table 1Chemical composition of type 304 stainless steel used (wt%).

C N Si Mn S P Cu Co B Ni Cr Fe

60.035 60.080 61.00 62.00 60.015 60.030 61.00 60.06 60.0018 9.00–10.00 18.50–20.00 Bal.

Table 2Testing conditions in the present work.

Parameter Parameter range

Inlet waterDO 3000 ± 10 ppbConductivity 55–75 nS/cm

Flow rate 8–9 L/hPressure 10 MPaTemperature in autoclave 290 ± 0.5 �C

12 16 20 24 28 32 36 40

612 h

388 h

100 h

26 h

b

b

bb

Cr2O3a-hematiteb-spinel

a

aa

a

Inte

nsity

(arb

itrar

y un

its)

2θ

a

α-Fe2O3

1 h

Fig. 2. XRD patterns of the oxide films formed on type 304 SS exposed to 290 �Cwater containing 3 ppm O2 for different time (Cu Ka radiation).

100 200 300 400 500 600 700

1000 h

612 h388 h

100 h

26 h

a-hematite

a

a

aa

a

Inte

nsity

(arb

itrar

y un

its)

Raman shift (cm-1)

a

1 h

Fig. 3. Raman spectra of the oxide films formed on type 304 SS exposed to 290 �Cwater containing 3 ppm O2 for different time.

100 200 300 400 500 600 700

Raman shift (cm-1)

1000 h (abraded)

a-hematiteb-spinel

bb

b

b

b aa

aa

a

a

Inte

nsity

(arb

itrar

y un

its)

1000 h

Fig. 4. Raman spectra of the oxide film formed on type 304 SS exposed to 290 �Cwater containing 3 ppm O2 for 1000 h before and after abrasion.

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exposed to 290 �C water containing 3 ppm O2 mainly consist ofhematite phase. The peaks corresponding to hematite in the XRDpatterns (Fig. 2) range between that for a-Fe2O3 and Cr2O3, andXPS spectra (Fig. 7) indicate that the oxidized metallic elementswere mainly Fe3+ and Cr3+, so the hematite structure is non-stoichi-ometric in composition and could be formulated as a-(Fe, Cr)2O3. Itshould be noted that the Raman peaks of hematite appear afteronly 1 h immersion and do not change with increasing immersiontime (Fig. 3). So hematite phase could be formed quickly afterimmersion and kept developing with increasing immersion time.Weak peaks of spinel are detected in the XRD patterns and alsoin the Raman spectra of specimen (immersed for 1000 h) afterabrasion (Fig. 4). So the signals corresponding to spinel must comefrom the inner layer as reported by the previous work [3–5]. Theinner spinel could not be detected with the Raman system beforeabrasion because the laser at 532 nm has low penetrability. Thephase structure of oxide layer in this work agrees well with ourprevious work [11] except for different relative intensity of thesetwo oxides. The present result is basically consistent with the pre-vious work [3–5] and the thermodynamic prediction [19].

According to SEM observation of the oxide films (Fig. 6), theoxide particles appear irregular shape with curving sides and bluntangles [3,4,11]. Apparently, such morphological features of hema-tite oxide particle differ from those of spinel particle havingstraight sides and planar faces [7,8,11]. The size of the oxide parti-cles is inhomogeneous with the large ones dispersed on the surfaceand the small ones developing from the subsurface layer (Fig. 6a).The surface morphology evolved with increasing immersion time.After 1 h immersion, very fine hematite oxide particles nucleated(Fig. 5a). Then the oxide nuclei grew up to certain size and ceasedto develop; while the relatively small particles gradually grew out-wards from the subsurface layer, resulting in a more compact sur-face layer of oxide film (Figs. 5b–f and 6).

At the early stage of oxidization, the concentration of Ni and Fein the surface layer of oxide films decreases remarkably, while Cr isnotably enriched (Fig. 8). Such Cr enrichment is surmised to becaused by selective dissolution of Ni and Fe. After 1 h immersion,it is found that from the outer to inner layer of oxide film, Cr con-tent gradually decreases to the level similar to the matrix, while Nicontent and Fe content gradually increase to the level similar to the

Fig. 5. SEM morphologies of the oxide films formed on type 304 SS exposed to 290 �C water containing 3 ppm O2 for (a) 1 h, (b) 26 h, (c) 100 h, (d) 388 h, (e) 612 h and (f)1000 h.

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matrix (Fig. 9). It is thought that at the early stage of oxidization, Feand Ni dissolved away from matrix prior to Cr and the remnantmetallic elements were oxidized through solid-state reactions,resulting in a Cr-rich surface layer. The enrichment of Cr in the sur-face layer of oxide film cannot be due to the precipitation of Crfrom testing solution, because the construction material of thetesting loop is stainless steel and the Cr concentration in testingsolution should be very low. The preferential outwards diffusionof Cr from underlying matrix could also be excluded because Crhas been proved to move more slowly than Fe or Ni in the oxides[6] and Cr depletion was not detected in the matrix just beneaththe oxide film (Fig. 9). So it is believed that the Cr enrichment inthe oxide film at the early stage of oxidization is due to the selec-tive dissolution of Fe and Ni prior to Cr. Some previous work [20–23] reported that preferential dissolution of Fe or Ni happened inthe passivation of Cr containing alloy at room temperature. Stell-wag [7] also proposed that selective dissolution of metallic ele-ments might play an important role in oxidization of stainlesssteels in high temperature water, though little evidence was pro-vided in his work. With increasing immersion time, Fe content inthe oxide film gradually increases, while Cr content decreases

(Fig. 8), which is believed to be due to the precipitation of dissolvedFe ion from testing solution. According to Fig. 10, it is evident thatafter a long-term immersion, Cr level in oxide film gradually in-creases while Fe level decreases from the outer to inner layer asopposed to Fig. 9. The total sputtering time was 690 s, suggestingan oxide thickness less than 140 nm. Considering the outer parti-cles are almost equiaxed and most of them have a diameter largerthan 140 nm (Fig. 5e), it can be deduced that the elemental compo-sition of a large single particle changes from the outer part to theinner part, which is consistent with our previous findings [11]. Thiscould be due to the different mechanism for nucleation and growthof oxide particles. After a Cr-rich oxide layer was formed by selec-tive dissolution of matrix and solid-state reactions, the subsequentgrowth of the oxide nuclei was accomplished by precipitation ofmetallic ions from testing solution. It has to be borne in mind thatthe testing loop was made of stainless steel, so Fe ion should be amajor part of the metallic ion in testing solution due to its selectivedissolution. As a result, the outer layer formed by precipitationshould be rich in Fe. The dissolution–precipitation mechanism inhigh temperature aqueous environments has been well docu-mented in the literature [7,9,11,24–28] and the Fe-enriched outerlayer was also supported by the previous work [3–5,7–10]. Robert-son [6] proposed that the duplex layered oxide formed in high tem-perature aqueous corrosion of stainless steel was due to non-selective corrosion and variant diffusion rates of metal ions inthe oxide. His proposal, however, could not explain the Cr enrich-ment at the early stage of oxidization and did not take precipita-tion into account. Ziemniak et al. [8] suggested that thecompositional difference between inner and outer oxide layerswas caused by incomplete mixing of normal and inverse spinels.This argument might not be applied here because the main oxidephase is hematite and compositional difference exists across a sin-gle oxide particle in the present work. In another work [29], Ziem-niak et al. found that alloy 600 lost weight during the earlyimmersion in high temperature water, but gained weight in excessof those accountable by the pickup of oxygen required to form cor-rosion oxide after longer time of immersion. Moreover, an excess ofFe and a deficiency of Ni were also found in the oxide layer. It waspossible that the weight loss during the early immersion wascaused by selective dissolution of samples and weight gain afterlong-term immersion was due to precipitation of extraneous ionsfrom testing solution.

Fig. 11 shows schematics of the oxidation process of type 304 SSexposed to oxygenated high temperature water in the presentwork. At first, Fe and Ni dissolved away from matrix prior to Crand the remnant metallic elements were oxidized through solid-state reactions, resulting in a surface layer of Cr enriched hematitenuclei (Fig. 11a). Then the hematite nuclei grew up through theprecipitation of extraneous metallic ions from testing solutionwhich were mainly Fe in the present work. Meanwhile, an innerlayer of spinel gradually developed probably due to the inward dif-fusion of oxidant [6,9,11,26] (Fig. 11b). The outmost oxide particlesgrew to a certain size and ceased to develop while the small parti-cles gradually developed from the subsurface layer and squeezedout, resulting in a more compact outer layer of hematite(Fig. 11c). Based on the present results and our previous work, itshould be mentioned here that the materials of testing equipments(autoclave and loop) may influence the solution conditions and inturn affect the oxidation process of materials in high temperatureaqueous environments [11].

5. Conclusions

The phase structures, morphologies and chemical compositionof the oxide films formed on type 304 SS exposed to 290 �C water

Fig. 6. SEM morphologies of the oxide films formed on type 304 SS exposed to290 �C water containing 3 ppm O2 for (a) 100 h and (b) 1000 h.

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545 540 535 530 525 520

690s180s30s

Inte

nsi

ty (

arb

itra

ry u

nit

s)In

ten

sity

(ar

bit

rary

un

its)

Binding energy (eV) Binding energy (eV)

M2O3

740 730 720 710 700 690

690s

180s30s

Inte

nsi

ty (

arb

itra

ry u

nit

s)

Fe3+(a) (b)

595 590 585 580 575 570 565 560

690s180s30s

Cr3+

Binding energy (eV)

890 880 870 860 850 840

690s

180s

Inte

nsi

ty (

arb

itra

ry u

nit

s)

Binding energy (eV)

Ni0

30s

(c) (d)

Fig. 7. (a) O 1s core level spectra, (b) Fe 2p3/2 core level spectra, (c) Cr 2p3/2 core level spectra, (d) Ni 2p3/2 core level spectra after different sputtering time for oxide filmformed on type 304 SS exposed to 290 �C water containing 3 ppm O2 for 612 h.

0 100 200 300 400 500 6000.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

Ni

Cr

Ato

mic

rat

io

[(F

e, C

r, o

r N

i)/(F

e+C

r+N

i)]

Duration time (h)

Fe%

Cr%

Ni%

Fe

sample without immersion

Fig. 8. Elemental composition of the surface layer of oxide films formed on type304 SS exposed to 290 �C water containing 3 ppm O2 for different time (after 30 ssputtering).

0 100 200 300 400 500 600 700

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

oxide filmAto

mic

rat

io[ (

Fe,

Cr,

or

Ni)/

(Fe+

Cr+

Ni)]

Sputtering time (s)

Fe%Cr%Ni%

matrix

Fig. 9. XPS depth profile for oxide film formed on type 304 SS exposed to 290 �Cwater containing 3 ppm O2 for 1 h.

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containing 3 ppm O2 were investigated and the related growthmechanism is discussed. The following conclusions can be drawn.

The main phase formed in oxide films is irregularly shapedhematite which is non-stoichiometric in composition and couldbe formulated as a-(Fe, Cr)2O3. Minor spinel was also detected inthe inner layer. At the early stage of oxidization, tiny Cr-rich oxidenuclei were formed firstly. Then with increasing immersion time,some oxide nuclei grew up to certain size and ceased to develop;meanwhile, relatively small particles gradually developed fromthe subsurface layer and squeezed out, resulting in a more compactouter layer. During immersion, Cr is first enriched on the surfacelayer after short immersion, and then decreases gradually to alow level. On the contrary, Fe is first depleted and then graduallybuilds up to a high level. It is proposed that the oxide nucleatedby solid-state reactions with the selective dissolution of Fe andNi, and then grew up through precipitation of extraneous metallicions from testing solution.

Acknowledgements

This study was jointly supported by the Science and TechnologyFoundation of China (50871113), the Major Scientific and Techno-logical Special Project (2010ZX06004-009), the Special Funds forthe Major State Basic Research Projects (2006CB605005) and theInnovation Fund of Institute of Metal Research (IMR), ChineseAcademy of Sciences (CAS). The authors are grateful to Peter L.Andresen from General Electric Global Research for his construc-tive suggestions on building the test loop.

References

[1] F.P. Ford, B.M. Gordon, R.M. Horn, Corrosion in the Nuclear Power Industry,ASM Handbook, vol. 13C, ASM International, OH, 2006, pp. 341–360.

[2] P.M. Scott, P. Combrade, Corrosion in the Nuclear Power Industry, ASMHandbook, vol. 13C, ASM International, OH, 2006, pp. 363–385.

[3] Y.-J. Kim, Corrosion 55 (1999) 81–88.[4] T. Miyazawa, T. Terachi, S. Uchida, T. Satoh, T. Tsukada, Y. Satoh, Y. Wada, H.

Hosokawa, J. Nucl. Sci. Technol. 43 (2006) 884–895.[5] T. Terachi, K. Arioka, Corrosion (2006). Houston, TX, NACE, Paper No. 06608.[6] J. Robertson, Corros. Sci. 32 (1991) 443–465.[7] B. Stellwag, Corros. Sci. 40 (1998) 337–370.[8] S.E. Ziemniak, M. Hanson, Corros. Sci. 44 (2002) 2209–2230.[9] X. Gao, X.-Q. Wu, Z.-E. Zhang, H. Guan, E.-H. Han, J. Supercrit. Fluids 42 (2007)

157–163.[10] M.-C. Sun, X.-Q. Wu, Z.-E. Zhang, E.-H. Han, Corros. Sci. 51 (2009) 1069–1072.[11] W.-J. Kuang, X.-Q. Wu, E.-H. Han, J.-C. Rao, Corros. Sci. (2010), doi:10.1016/

j.corsci.2010.07.015.[12] D. Thierry, D. Persson, C. Leygraf, N. Boucherit, A. Hugot-le Goff, Corros. Sci. 32

(1991) 273–284.[13] L.J. Oblonsky, T.M. Devine, Corros. Sci. 37 (1995) 17–41.[14] J.E. Maslar, W.S. Hurst, W.J. Bowers, J.H. Hendricks, M.I. Aquino, J. Electrochem.

Soc. 147 (2000) 2532–2542.[15] C.S. Kumai, T.M. Devine, Corrosion 63 (2007) 1101–1113.[16] J.C. Langevoort, I. Sutherland, L.J. Hanekamp, P.J. Gellings, Appl. Surf. Sci. 28

(1987) 167–179.[17] V.A. Maroni, C.A. Melendres, T.F. Kassner, R. Kumar, S. Siegel, J. Nucl. Mater.

172 (1990) 13–18.[18] H. Sun, X.-Q. Wu, E.-H. Han, Corros. Sci. 51 (2009) 2840–2847.[19] Y.-J. Kim, Corrosion 51 (1995) 849–860.[20] K. Asami, K. Hashimoto, S. Shimodaira, Corros. Sci. 18 (1978) 151–160.[21] H. Gunnar, S. Masahiro, L. Thomas, L. Christofer, S. Norio, Corros. Sci. 27 (1987)

937–946.[22] J.E. Castle, J.H. Qiu, Corros. Sci. 30 (1990) 429–438.[23] A. Kocijan, C. Donik, M. Jenko, Corros. Sci. 49 (2007) 2083–2098.[24] D.H. Lister, R.D. Davidson, E. Mcalpine, Corros. Sci. 27 (1987) 113–140.[25] C.S. Kumai, T.M. Devine, Corrosion 61 (2005) 201–218.[26] M.-C. Sun, X.-Q. Wu, Z.-E. Zhang, E.-H. Han, J. Supercrit. Fluids 47 (2008) 309–

317.[27] H. Sun, X.-Q. Wu, E.-H. Han, Corros. Sci. 51 (2009) 2565–2572.[28] J.-B. Huang, X.-Q. Wu, E.-H. Han, Corros. Sci. 51 (2009) 2976–2982.[29] S.E. Ziemniak, M. Hanson, Corros. Sci. 48 (2006) 498–521.

0 100 200 300 400 500 600 700

Sputtering time (s)

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

Ato

mic

rat

io[(

Fe,

Cr,

or

Ni)/

(Fe+

Cr+

Ni)]

Fe%Cr%Ni%

Fig. 10. XPS depth profile for oxide film formed on type 304 SS exposed to 290 �Cwater containing 3 ppm O2 for 612 h.

Fig. 11. Schematics of oxidation process of type 304 SS exposed to 290 �C watercontaining 3 ppm O2 in this study.

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