Jiang Wen, Zhao Kunyu
School of Chemistry and Chemical Engineering, Kunming University, Kunming 650214, China.
Department of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093, China.
Materials (Basel). 2023 Feb 3;16(3):1302. doi: 10.3390/ma16031302.
We investigated the effect of Cu on the formation of reversed austenite in super martensitic stainless steel by using X-ray diffraction (XRD), a transmission electron microscope (TEM) and an energy-dispersive spectrometer (EDS). Our results showed that the microstructure of the steels comprised tempered martensite and diffused reversed austenite after the steels were quenched at 1050 °C and tempered at 550-750 °C. The volume fraction of reversed austenite in the steel with 3 wt.% of Cu (3Cu) was more than that with 1.5 wt.% of Cu (1.5Cu). The transmission electron microscope results revealed that the reversed austenite in 1.5Cu steel mainly had the shape of a thin strip, while that in 3Cu steel had a block shape. The nucleation points and degree of Ni enrichment of reversed austenite in 3Cu steel were higher than those in 1.5Cu steel. The reversed austenite was more likely to grow in ε-Cu enriched regions. Therefore, Cu can promote reversed austenite nucleation and growth. The mechanical properties of 3 Cu steel are obviously better than those of 1.5Cu steel when tempered at 550-650 °C.
我们通过使用X射线衍射（XRD）、透射电子显微镜（TEM）和能量色散光谱仪（EDS），研究了铜对超级马氏体不锈钢中逆奥氏体形成的影响。我们的结果表明，在1050℃淬火并在550 - 750℃回火后，钢的微观结构由回火马氏体和弥散的逆奥氏体组成。含3 wt.%铜（3Cu）的钢中逆奥氏体的体积分数高于含1.5 wt.%铜（1.5Cu）的钢。透射电子显微镜结果显示，1.5Cu钢中的逆奥氏体主要呈细条状，而3Cu钢中的逆奥氏体呈块状。3Cu钢中逆奥氏体的形核点和镍富集程度高于1.5Cu钢。逆奥氏体更倾向于在富ε - Cu区域生长。因此，铜可促进逆奥氏体的形核和生长。在550 - 650℃回火时，3Cu钢的力学性能明显优于1.5Cu钢。
