Liu Guolong, Liu Jingbao, Zhang Jie, Zhang Minghe, Feng Yunli
College of Metallurgy and Energy, North China University of Science and Technology, Tangshan 063210, China.
Technology Center, HBIS Group Tangsteel Company, Tangshan 063016, China.
Materials (Basel). 2021 Nov 15;14(22):6900. doi: 10.3390/ma14226900.
The microstructure evolution and mechanical properties of medium carbon martensitic steel during the warm rolling and annealing process were studied by scanning electron microscope (SEM), electron back scattering diffraction (EBSD), and electronic universal testing machine. The results showed that the microstructure of ferrite matrix with mass dispersive cementite particles was obtained by decomposition of martensitic in medium-carbon martensitic steel after warm rolling. The grain size of ferrite was ~0.53 μm, the yield strength and tensile strength were 951 MPa and 968 MPa, respectively, and the total elongation rate was 11.5% after warm rolling at 600 °C. Additionally, after the next 4 h of annealing, the grain size of ferrite and particle size of cementite increased to ~1.35 μm and ~360 nm and the yield strength and tensile strength decreased to 600 MPa and 645 MPa, respectively, with a total elongation increases of 20.9%. The strength of the material increased with increasing strain rate in tension, and the yield-to-tensile strength ratio increased from 0.92 to 0.94 and maintained good plasticity.
采用扫描电子显微镜（SEM）、电子背散射衍射（EBSD）和电子万能试验机研究了中碳马氏体钢在温轧和退火过程中的微观组织演变及力学性能。结果表明，中碳马氏体钢温轧后马氏体分解得到铁素体基体加大量弥散渗碳体颗粒的组织。600℃温轧后铁素体晶粒尺寸约为0.53μm，屈服强度和抗拉强度分别为951MPa和968MPa，总伸长率为11.5%。此外，随后4h退火后，铁素体晶粒尺寸和渗碳体颗粒尺寸分别增大到约1.35μm和约360nm，屈服强度和抗拉强度分别降至600MPa和645MPa，总伸长率提高到20.9%。拉伸时材料强度随应变速率增加而提高，屈强比从0.92提高到0.94，并保持良好的塑性。
