Effect of Pre-oxidation on Corrosion Behavior of Three Kinds of Superalloys in Impure Helium of High-temperature Reactor

被引：0
|
作者：
Li H. [1 ]
Zheng W. [1 ]
Yin H. [1 ]
Wang Q. [1 ]
He X. [1 ]
Ma T. [1 ]
Yang X. [1 ]
机构：
[1] Institute of Nuclear Energy and New Energy Technology, Tsinghua University, Beijing
来源：
Yuanzineng Kexue Jishu/Atomic Energy Science and Technology | 2022年 / 56卷 / 06期
关键词：
Carburizing; High-temperature gas cooled reactor; Oxidation; Pre-oxidation; Superalloy;
D O I：
10.7538/yzk.2021.youxian.0486
中图分类号：
学科分类号：
摘要：
Nuclear energy is a clean, efficient and high-quality modern energy. It is of great significance to alleviate energy shortage, improve ecological environment and optimize energy structure. As a kind of the fourth generation nuclear power system, high-temperature reactor has good inherent safety and economy, high power generation efficiency and wide application of process heat. The superior performance of high-temperature reactor is closely related to the excellent alloy materials. Due to the high temperature of helium in the primary circuit of high-temperature reactor, a trace of graphite dust generates certain gas impurities after chemical reaction. At the same time, due to the introduction of impure helium and gas leakage, the helium in the main coolant of high-temperature reactor contains trace gas impurities such as CO, H2O, CH4, CO2, N2 and O2, and the concentration of impurities is in the order of ppm. Impurities in high-temperature environment will cause corrosion, oxidation, carburization and decarburization of alloy materials in high-temperature reactor steam generator and intermediate heat exchanger, and affect the reliability and safety of equipment. Inconel 617, Hastelloy X and Incoloy 800H are three candidate materials for high-temperature reactor intermediate heat exchanger and steam generator equipment. According to the studies, it shows that the chromium rich oxide layer formed on the surface of NiCr alloy at high temperature is an important factor to prevent serious corrosion of the alloy at high temperature. In this paper, the corrosion behavior of three alloys in high temperature helium containing ppm impurity was studied, and the effect of pre-oxidation in extremely low oxygen partial pressure He-1 atmosphere on the corrosion behavior of three alloys was explored. After the test, the corrosion results of the alloy with or without pre-oxidation were analyzed by weighing, scanning electron microscope, X-ray energy spectrum analysis, electron probe microanalyzer and carbon sulfur analyzer. The results show that the three alloys have different oxidation and carburization phenomena, and the carburization behavior has ended when they are corroded for 50 h. CH4 plays an important role in the carburizing corrosion process of alloys. Pre-oxidation has no obvious improvement on the corrosion resistance of Hastelloy X alloy, less improvement on the oxidation resistance and carburizing capacity of Inconel 617 alloy and less improvement on the carburizing corrosion resistance of Incoloy 800H alloy. According to the test results, it can be concluded that the oxide layer formed by short-time pre-oxidation in extremely low oxygen partial pressure He-1 atmosphere is not necessary to improve the corrosion resistance of the alloy. © 2022, Editorial Board of Atomic Energy Science and Technology. All right reserved.
引用
收藏
页码：1069 / 1077
页数：8
相关论文
共 15 条
  • [1] 2, pp. 40-41, (2017)
  • [2] ZHANG Zuoyi, WU Zongxin, WANG Dazhong, Et al., Development strategy of high temperature gas cooled reactor in China, Engineering Science, 21, 1, pp. 12-19, (2019)
  • [3] QUADAKKERS W J., Corrosion of alloys in the primary circuit helium of high temperature gas cooled reactors, Part Ⅱ: Experimental results, Materials and Corrosion, 36, 8, pp. 335-347, (1985)
  • [4] HAMAMOTO S, SAKABA N, TAKEDA Y., Control method of purification system of helium coolant for suppressing decarburization of heat-resistant alloy used in very high temperature gas cooling reactors, Transactions of the Atomic Energy Society of Japan, 9, 2, pp. 174-182, (2010)
  • [5] LI Jufeng, YANG Sengai, YU Liyuan, Et al., First time localization practice of steam generator tubes of Incoloy 800H for nuclear power plant, Hot Working Technology, 44, 18, pp. 92-94, (2015)
  • [6] KURATA Y, OGAWA Y, NAKAJIMA H., Effect of carburizing helium environment on creep-behavior of Ni-base heat-resistant alloys for high-temperature gas-cooled reactors, Tetsu to Hagane-Journal of the Iron and Steel Institute of Japan, 74, 11, pp. 2185-2192, (1988)
  • [7] KURATA Y, OGAWA Y, NAKAJIMA H., Effect of decarburizing helium environment on creep-behavior of Ni-base heat-resistant alloys for high-temperature gas-cooled reactors, Tetsu to Hagane-Journal of the Iron and Steel Institute of Japan, 74, 2, pp. 380-387, (1988)
  • [8] QUADAKKERS W J, SCHUSTER H., Corrosion of high temperature alloys in the primary circuit helium of high temperature gas cooled reactors, Part Ⅰ: Theoretical background, Materials and Corrosion, 36, 8, pp. 141-150, (1985)
  • [9] WANG Qiuhao, LI Haoxiang, ZHENG Wei, Et al., Research and model analysis on the effect of coolant impurities on high temperature properties of superalloys in high temperature gas cooled reactor, Nuclear Techniques, 43, 4, pp. 37-42, (2020)
  • [10] ZHU Jiang, LI Zhihui, Research on quality of helium gas in primary system of 10 MW High-Temperature Gas-Cooling Reactor, Atomic Energy Science and Technology, 44, pp. 274-278, (2010)
12