1 School of Materials and Metallurgy, Wuhan University of Science and Technology, Wuhan 430080, Hubei, China 2 Wuhan Branch of Baosteel Central Research Institute (R&D Center) of Wuhan Iron & Steel Co., Ltd., Wuhan 430080, Hubei, China 3 Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China
Influence of inclusions on hydrogen-induced delayed cracking in hot stamping steels
1 School of Materials and Metallurgy, Wuhan University of Science and Technology, Wuhan 430080, Hubei, China 2 Wuhan Branch of Baosteel Central Research Institute (R&D Center) of Wuhan Iron & Steel Co., Ltd., Wuhan 430080, Hubei, China 3 Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China
摘要 The hydrogen-induced delayed cracking (HIDC) behaviors of two types of 1500 MPa grade hot stamping steels (HSSs) have been investigated by the method of slow strain rate tensile test and hydrogen permeation, where one is manufactured by compact strip production (CSP) process which is a revolution to the traditional HSS and the other by the traditional cold rolling process. The results show that the performance of HSS produced by CSP is superior to that of the traditional HSS, due to lower hydrogen embrittlement index, lower hydrogen diffusion coefficient and lower hydrogen content. It has been found that HIDC behavior is closely associated with inclusions. The inclusions of HSS produced by CSP are mainly spherical Al–Ca–O and CaS, while the inclusions in the traditional HSS are TiN 1 Al2O3 ? MnS with sharp edges and corners. Based on these results, the influence of composition, shape and distribution of inclusions in HSS on HIDC and the mechanism of HIDC from the perspective of inclusions were analyzed and discussed.
Abstract:The hydrogen-induced delayed cracking (HIDC) behaviors of two types of 1500 MPa grade hot stamping steels (HSSs) have been investigated by the method of slow strain rate tensile test and hydrogen permeation, where one is manufactured by compact strip production (CSP) process which is a revolution to the traditional HSS and the other by the traditional cold rolling process. The results show that the performance of HSS produced by CSP is superior to that of the traditional HSS, due to lower hydrogen embrittlement index, lower hydrogen diffusion coefficient and lower hydrogen content. It has been found that HIDC behavior is closely associated with inclusions. The inclusions of HSS produced by CSP are mainly spherical Al–Ca–O and CaS, while the inclusions in the traditional HSS are TiN 1 Al2O3 ? MnS with sharp edges and corners. Based on these results, the influence of composition, shape and distribution of inclusions in HSS on HIDC and the mechanism of HIDC from the perspective of inclusions were analyzed and discussed.
Yong Chen,Jing Liu,Feng Huang, et al. Influence of inclusions on hydrogen-induced delayed cracking in hot stamping steels[J]. Journal of Iron and Steel Research International, 2019, 26(11): 1199-1208.