Tian Yan, Zhao Mingchun, Liu Wenjian, Zhang Jimou, Zhang Min, Li Hongying, Yin Dengfeng, Atrens Andrej
School of Materials Science and Engineering, Central South University, Changsha 410083, China.
Xiangtan Iron & Steel Co., Ltd. of Hunan Valin, Xiangtan 411101, China.
Materials (Basel). 2021 Apr 29;14(9):2309. doi: 10.3390/ma14092309.
This work investigated the tensile characteristics of plain C-Mn steel with an ultrafine grained ferrite/cementite (UGF/C) microstructure and coarse-grained ferrite/pearlite (CGF/P) microstructure. The tensile tests were performed at temperatures between 77 K and 323 K. The lower yield and the ultimate tensile strengths were significantly increased when the microstructure was changed from the CGF/P to the UGF/C microstructures, but the total elongation and the uniform elongation decreased. A microstructural change from the CGF/P microstructure to the UGF/C microstructure had an influence on the athermal component of the lower yield and the ultimate tensile strengths but not on the thermal component. The UGF/C microstructure with a higher carbon content provided a higher strength without losing ductility because cementite particles restrained necking.
本研究调查了具有超细晶粒铁素体/渗碳体（UGF/C）微观结构和粗晶粒铁素体/珠光体（CGF/P）微观结构的普通C-Mn钢的拉伸特性。拉伸试验在77 K至323 K的温度范围内进行。当微观结构从CGF/P转变为UGF/C微观结构时，下屈服强度和抗拉强度显著提高，但总伸长率和均匀伸长率降低。从CGF/P微观结构到UGF/C微观结构的微观结构变化对下屈服强度和抗拉强度的无热分量有影响，但对热分量没有影响。具有较高碳含量的UGF/C微观结构在不损失延展性的情况下提供了更高的强度，因为渗碳体颗粒抑制了颈缩。
