Precipitation behaviors of second phase in toxic stainless steel shielding material

doi:10.13251/j.issn.0254-6051.2020.05.007

Abstract

Abstract: Precipitation behaviors of the second phase of toxic stainless steel was carried out by means of optical microscope (OM), scanning electron microscope (SEM) and X-ray diffraction (XRD), and the influence mechanism of the second phase precipitation on the stability of the matrix and rolling cracking was also analyzed. The results show that the second phase in the tested stainless steel is mainly Gd-Ni system, and its amount increases with the increase of Gd content. When the mass fraction of Gd increases from 1.87% to 7.87%, the area fraction of the second phase increases from 5.5% to 20.3%. Then, the precipitation of the second phase destroys the stability of the matrix structure. With the increase of Gd content, the matrix structure undergoes the transformation from single-phase austenite to austenite plus ferrite, and finally to single-phase ferrite. The precipitation of the second phase reduces the plasticity of the stainless steel and promotes the initiation and development of rolling cracks.

Key words: toxic stainless steel, second phase, precipitate

CLC Number:

TL34

Zhao Yong, Liu Yunming, Gu Mingfei, Pan Qianfu, Zhang Hongzhi, Qiang Rui, Wang Luquan. Precipitation behaviors of second phase in toxic stainless steel shielding material[J]. Heat Treatment of Metals, 2020, 45(5): 34-39.

References

[1]韩毅, 陈法国, 于伟跃, 等. 中子屏蔽材料研究现状[J]. 材料导报, 2015, 29(2): 483-488.
Han Yi, Chen Faguo, Yu Weiyue, et al. Investigation of the research status of neutron shielding materials[J]. Materials Review, 2015, 29(2): 483-488.
[2]Kurban M, Erb U, Aust K T. A grain boundary characterization study of boron segregation and carbide precipitation in alloy 304 austenitic stainless steel[J]. Scripta Materialia, 2006, 54(6): 1053-1058.
[3]Bastürk M, Arztmann J, Jerlich W, et al. Analysis of neutron attenuation in boron-alloyed stainless steel with neutron radiography and JEN-3 gauge[J]. Journal of Nuclear Materials, 2005, 341(2): 189-200.
[4]Özbek I, Konduk B A, Bindal C, et al. Characterization of borided AISI 316L stainless steel implant[J]. Vacuum, 2002, 65(3): 521-525.
[5]Williams T M, Stoneham A M, Harries D R. The segregation of boron to grain boundaries in solution-treated type 316 austenitic stainless steel[J]. Metal Science, 1976, 10(1): 14-19.
[6]Khan Z. Influence of gadolinium on the microstructure and mechanical properties of steel and stainless steel[J]. Journal of the Southern African Institute of Mining and Metallurgy, 2012, 112(4): 309-321.
[7]Robino C V, Michael J R, DuPont J N, et al. Development of Gd-enriched alloys for spent nuclear fuel applications—part Ⅰ: Preliminary characterization of small scale Gd-enriched stainless steels[J]. Journal of Materials Engineering and Performance, 2003, 12(2): 206-214.
[8]DuPont J N, Robino C V, Michael J R, et al. Physical and welding metallurgy of Gd-enriched austenitic alloys for spent nuclear fuel applications—part Ⅰ: Stainless steel alloys[J]. Welding Journal, 2004, 83(11): 289-300.
[9]DuPont J N, Robino C V, Stephens Jr J J, et al. Preliminary microstructural characterization of gadolinium-enriched stainless steels for spent nuclear fuel baskets (title change from A)[R]. Sandia National Labs, Albuquerque, NM (US); Sandia National Labs, Livermore, CA (US), 2000.
[10]Schmidt M L, Del Corso G J, Klankowski K A, et al. Review of the development and testing of a new family of boron and gadolinium-bearing dual thermal neutron absorbing alloys-13026[C]//United States: N. p., 2013. https://www.osti.gov/biblio/22224834.
[11]DuPont J N, Robino C V, Anderson T D. Influence of Gd and B on solidification behaviour and weldability of Ni-Cr-Mo alloy[J]. Science and Technology of Welding and Joining, 2008, 13(6): 550-565.
[12]Susan D F, Robino C V, Minicozzi M J, et al. A solidification diagram for Ni-Cr-Mo-Gd alloys estimated by quantitative microstructural characterization and thermal analysis[J]. Metallurgical and Materials Transactions A, 2006, 37(9): 2817-2825.
[13]Choi Y, Moon B M, Sohn D S. Fabrication of Gd containing duplex stainless steel sheet for neutron absorbing structural materials[J]. Nuclear Engineering and Technology, 2013, 45(5): 689-694.
[14]Lim J, Ahn J H, Moon B M, et al. Influence of gadolinium addition on mechanical and corrosion properties of 2205 duplex stainless steel[J]. Journal of Korea Foundry Society, 2015, 35(6): 163-169.
[15]Lim J, Jung H D, Ahn J H, et al. Microstructure and fracture property of 1A grade duplex stainless steel with the addition of gadolinium[J]. Journal of Korea Foundry Society, 2016, 36(1): 24-31.
[16]张阳, 王福明, 唐郑磊, 等. SXQ500/550D钢奥氏体晶粒长大行为及其影响因素[J]. 金属热处理, 2019, 44(8): 110-118.
Zhang Yang, Wang Fuming, Tang Zhenglei, et al. Austenite grain growth behavior and its influencing factors of SXQ500/550D steel[J]. Heat Treatment of Metals, 2019, 44(8): 110-118.
[17]张迎晖, 谢健明, 刘欣, 等. 微合金化S355钢的第二相析出行为[J]. 金属热处理, 2018, 43(8): 55-59.
Zhang Yinghui, Xie Jianming, Liu Xin, et al. Secondary phase precipitation behavior of microalloyed S355 steel[J]. Heat Treatment of Metals, 2018, 43(8): 55-59.
[18]韩世绪, 冯运莉, 白敏, 等. 含铌取向硅钢第二相沉淀析出相变动力学计算[J]. 金属热处理, 2019, 44(7): 194-197.
Han Shixu, Feng Yunli, Bai Min, et al. Dynamics calculations of secondary phase precipitation in Nb-bearing oriented silicon steel[J]. Heat Treatment of Metals, 2019, 44(7): 194-197.
[19]武绍文, 张彩军, 郑非凡, 等. EH40钢中第二相粒子对奥氏体尺寸的影响[J]. 金属热处理, 2019, 44(7): 88-92.
Wu Shaowen, Zhang Caijun, Zheng Feifan, et al. Effect of second phase particles on austenite grain size in EH40 steel[J]. Heat Treatment of Metals, 2019, 44(7): 88-92.