Trans-twins stress corrosion cracking behaviors of Alloy 690TT in lead-containing caustic solution at 330 degrees C

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	Trans-twins stress corrosion cracking behaviors of Alloy 690TT in lead-containing caustic solution at 330 degrees C; Trans-twins stress corrosion cracking behaviors of Alloy 690TT in lead-containing caustic solution at 330 degrees C
	Z. M. Zhang; J. Q. Wang; E. H. Han; W. Ke
	2011 ; 2011
发表期刊	Nuclear Engineering and Design ; Nuclear Engineering and Design
ISSN	0029-5493 ; 0029-5493
卷号	241 期号:12 页码:4944-4952
摘要	Twin grain boundaries (GBs) are found to be inherently resistant to stress corrosion cracking (SCC), which has become one of the main failure mechanisms of steam generator (SG) tubing since the 1980s and brings huge economic losses to the nuclear power plants. As it is a widely used material for SG tubing, the SCC-resistance of the twins in Alloy 690TT in 10 wt.% sodium hydroxide solution with 100 ppm litharge at 330 degrees C was studied using C-ring samples. The relationship between the crack paths, twin GBs and the residual strains in the studied areas were analyzed using an environmental scanning electron microscope (ESEM) equipped with electron backscatter diffraction (EBSD) equipment. A continuously stressed C-ring sample without immersion was used to evaluate the effect of residual stress or strain on the microstructure of the twin GBs. The oxides at the crack paths were analyzed by an energy dispersive spectroscopy (EDS). The results show that many twin GBs are cracked during crack propagation. There are more twins with large deviations from the ideal Sigma 3 twin misorientation in the studied area where the residual strain is high. In situ EBSD analyses verify that higher residual strain causes twins to deviate from the ideal twin microrientation and can even promote twins transiting into random high angle grain boundaries, when the residual strain is high enough. The EDS result illustrates that litharge accelerates the dissolution of the chromium and nickel in the matrix. Overall, the SCC-resistance of the twins in Alloy 690TT in the studied solution is reduced by the destruction of the ideal microrientation of the twin GBs and the preferential dissolution of chromium and nickel at the crack paths. Higher residual strain on the Alloy 690TT and deleterious impurities in the circulating secondary water should be eliminated during the operation of nuclear power plants. (C) 2011 Elsevier B.V. All rights reserved.; Twin grain boundaries (GBs) are found to be inherently resistant to stress corrosion cracking (SCC), which has become one of the main failure mechanisms of steam generator (SG) tubing since the 1980s and brings huge economic losses to the nuclear power plants. As it is a widely used material for SG tubing, the SCC-resistance of the twins in Alloy 690TT in 10 wt.% sodium hydroxide solution with 100 ppm litharge at 330 degrees C was studied using C-ring samples. The relationship between the crack paths, twin GBs and the residual strains in the studied areas were analyzed using an environmental scanning electron microscope (ESEM) equipped with electron backscatter diffraction (EBSD) equipment. A continuously stressed C-ring sample without immersion was used to evaluate the effect of residual stress or strain on the microstructure of the twin GBs. The oxides at the crack paths were analyzed by an energy dispersive spectroscopy (EDS). The results show that many twin GBs are cracked during crack propagation. There are more twins with large deviations from the ideal Sigma 3 twin misorientation in the studied area where the residual strain is high. In situ EBSD analyses verify that higher residual strain causes twins to deviate from the ideal twin microrientation and can even promote twins transiting into random high angle grain boundaries, when the residual strain is high enough. The EDS result illustrates that litharge accelerates the dissolution of the chromium and nickel in the matrix. Overall, the SCC-resistance of the twins in Alloy 690TT in the studied solution is reduced by the destruction of the ideal microrientation of the twin GBs and the preferential dissolution of chromium and nickel at the crack paths. Higher residual strain on the Alloy 690TT and deleterious impurities in the circulating secondary water should be eliminated during the operation of nuclear power plants. (C) 2011 Elsevier B.V. All rights reserved.
部门归属	[zhang, z. m.; wang, j. q.; han, e. -h.; ke, w.] chinese acad sci, inst met res, state key lab corros & protect, shenyang 110016, peoples r china.;wang, jq (reprint author), chinese acad sci, inst met res, state key lab corros & protect, 62 wencui rd, shenyang 110016, peoples r china;wangjianqiu@imr.ac.cn ; [zhang, z. m.; wang, j. q.; han, e. -h.; ke, w.] chinese acad sci, inst met res, state key lab corros & protect, shenyang 110016, peoples r china.;wang, jq (reprint author), chinese acad sci, inst met res, state key lab corros & protect, 62 wencui rd, shenyang 110016, peoples r china;wangjianqiu@imr.ac.cn
关键词	High-temperature Water High-temperature Water Grain-boundary Misorientation Grain-boundary Misorientation Ni-base Alloys Ni-base Alloys Chromium Depletion Chromium Depletion Quantitative Assessment Quantitative Assessment Secondary-side Secondary-side Heat-treatment Heat-treatment Resistance Resistance Oxide Oxide Microstructure Microstructure
URL	查看原文 ; 查看原文
WOS记录号	WOS:000298764900040 ; WOS:000298764900040
引用统计	被引频次：16[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/30946
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	Z. M. Zhang,J. Q. Wang,E. H. Han,et al. Trans-twins stress corrosion cracking behaviors of Alloy 690TT in lead-containing caustic solution at 330 degrees C, Trans-twins stress corrosion cracking behaviors of Alloy 690TT in lead-containing caustic solution at 330 degrees C[J]. Nuclear Engineering and Design, Nuclear Engineering and Design,2011, 2011,241, 241(12):4944-4952, 4944-4952.
APA	Z. M. Zhang,J. Q. Wang,E. H. Han,&W. Ke.(2011).Trans-twins stress corrosion cracking behaviors of Alloy 690TT in lead-containing caustic solution at 330 degrees C.Nuclear Engineering and Design,241(12),4944-4952.
MLA	Z. M. Zhang,et al."Trans-twins stress corrosion cracking behaviors of Alloy 690TT in lead-containing caustic solution at 330 degrees C".Nuclear Engineering and Design 241.12(2011):4944-4952.