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| Hot corrosion behaviors of Super 304H austenitic stainless steel precoated in Na2SO4–25%NaCl mixture salt film |
| Ping Li1 . Ting-ju Li1 . Jie Zhao1 . Sheng-jiao Pang1 |
| 1 College of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China |
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Abstract Hot corrosion rates of Super 304H austenitic stainless steel pre-coated in Na2SO4–25%NaCl mixture salt .lm in air at 650 C and 750 C have been investigated by corrosion kinetics curves. The corrosion products are examined by means of X-ray diffraction and scanning electron microscopy coupled with energy-dispersive spectrometer, and electron probe micro-analyzer to analyze the scale structure and element distribution of the cross section. The results indicate that the kinetics curves are similar and display parabolic growth, and the mass gain obviously increases with the increasing temperature. A two-layer oxide scale composed of Fe oxides containing CuFe2O4 and Cr2O3 forms on the surface of the alloy and easily exfoliates with extending corrosion time or with improving corrosion temperature. Moreover, a corrosion-affected zone with micropores and micro-cracks appears beneath the oxide scale. It is concluded that the selective oxidation occurs and a protective oxide scale forms at the early corrosion stage. The melt salts destroy the integrity of the oxide scale and accelerate hot corrosion of the alloy by the cyclical oxidation–chlorination during the further corrosion processing. In addition, internal sulfidation also contributes to the corrosion of the alloy.
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Received: 17 July 2017
Published: 07 January 2019
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| Cite this article: |
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LI Yan-Ju,DIAO Jie,PANG SHENG-JIAO. Hot corrosion behaviors of Super 304H austenitic stainless steel precoated in Na2SO4–25%NaCl mixture salt film[J]. Journal of Iron and Steel Research International, 2018, 25(11): 1149-1155.
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| [1] |
Iseda A, Okada H, Sembaan H and Igarashi M. Long term creep properties and microstructure of SUPER304H, TP347HFG and HR3C for A-USC boilers. Energy Materials.2007, 2(4):199-206.
|
| [2] |
Lai GY. High temperature corrosion of engineering alloys. Metals Park: American society for metals; OH, 1990. 154.
|
| [3] |
Y. Shinata, F. Takahashi, K. Hashiura. NaCl-Induced Hot Corrosion of Stainless Steels.Mater. Sci. Eng. 1987 (87):399-405.
|
| [4] |
QIN Ting-sheng, LI Shu-shan. Study on the mechanism of chlorine Corrosion under high temperature of boiler heating surface in power plant [J]. Coal. 2001,(2): 42-52.
|
| [5] |
Y. Bourhis, C.St. John. Na2SO4-and NaCl-Induced hot corrosion of six nickel-base superalloys. Oxid. Met. 1975,9 (6) :507-528.
|
| [6] |
Y. Niu, F. Gesmundo, F. Viani, W. Wu. The corrosion of Ni3Al in a combustion gas with and without Na2SO4 -NaCl deposits at 600–800°C.Oxid. Met. 1994, 42(3):265-284.
|
| [7] |
HIRAMATSU N, UEMATSU Y, TANAKA T, et al. Effects of alloying elements on NaCl-induced hot corrosion of stainless steel[J].Mater Sci Eng A. 1989，120-121(1):319一328.
|
| [8] |
Y H.WANC F H.WU W T. Corrosion behavior Cr with a solid NaCl deposit in O2 plus water vapor[J]. Oxid Met. 2000,54(5-6):457-471.
|
| [9] |
SHU Y, WANG F.Influence of Cr content on the Corrosion of Fe-Cr alloys: The synergistic effect of NaCl and water vapor [J].Oxid Met. 2003,59(3-4):201-204.
|
| [10] |
D.M. Johnson, D.P. Whittle, J. Stringer. Mechanisms of Na2SO4-induced accelerated oxidation Corros. Sci. 1975,15 (6-12):721-739.
|
| [11] |
Viswanaathan R,Purgert R,Rao U. Materials for Ultra-supercritical coal-fired power plant boilers[A].Proceedings of the 2nd Regional Conference on Energy Technology Towards a Clean Environment[C].Thailand,Phuket:2003.
|
| [12] |
A. Iseda: Proc. 14th Conference on ‘Electric power supply industry’, CEPSI, Fukuoka, Japan, ovember 2002, 350–355.
|
| [13] |
WANG L L, ZHU L H, WANG Q J. Strengthening mechanism of super 304H heat-resistant steel [J]. Trans Mater Heat Treat，2011，32(6):127-131.
|
| [14] |
SMITH G D, SIZEK H W. Introduction of an advanced super heater alloy for coal-fired boilers [D]. Corrosion 2000 [s.l]. Houston: NACE International，2000.
|
| [15] |
ISEDA A, OKADA H, SEMBA H, et al. Long term creep properties and microstructure of SUPER304H,TP347HFG and HR3C for A-USC boilers[J]. Energy Materials: Materials Science and Engineering for Energy Systems，2007，2(4)：199—206.
|
| [16] |
KIM J H, KIM D I, SHIM J H, et al. Investigation into the high temperature oxidation of Cu-bearing austenitic stainless steel using simultaneous electron backscatter diffraction-energy dispersive spectroscopy analysis [J].Corrosion Science.2013 (77):397-402.
|
| [17] |
Deb D, Lyer S R, Radhakrishnan V M. A comparative study of oxidation and hot corrosion of a cast nickel base super alloy in different corrosive environment[J].Materials Letters,1996,29(1):19-23.
|
| [18] |
A.U. Seybolt. Internal oxidation in heat-resisting stainless steels caused by presence of halides. Oxid. Met. 2 (1970) 161-171.
|
| [19] |
Tsaur CC, Rock JC,Wang CJ, Su YH. The hot corrosion of 310 stainless steel with pre-coated NaCl/Na2SO4 mixtures at 750℃. Mater Chem Phys. 2005(89):445–53.
|
| [20] |
Knacke O, Kubaschewski O, Hesselmann K. Thermomechanical properties of inorganic substance. Berlin, Heidelberg: Springer-Verlag; 1991.
|
| [21] |
Shinata Y. Accelerated oxidation rate of chromium induced by sodium chloride[J]. Oxide Met 1987,27(5/6):315–320.
|
| [22] |
ZHAO S Q, XIE X S, SMITH U D, et al. The corrosion of INC'ONEI. alloy 740 in simulated environments for pulverized coal fired boiler[J]. Materials Chemistry and Physics.2005,90(2):275-281.
|
|
|
|
2018, Vol. 25 
