论文部分内容阅读
采用拉伸、冲击、硬度等力学性能的测试以及金相组织观察、XRD、SEM分析了27SiMn钢在淬火温度为770～830℃、等温温度为360～420℃和等温时间为10～90min时,显微组织和力学性能的变化规律。结果表明,通过790℃加热保温50min,380℃等温20min,空冷到室温后可以得到铁素体+贝氏体+残余奥氏体的三相组织,得到最好的综合性能,Rm×A5为27 225MPa×%,其中抗拉强度Rm为825MPa,伸长率A5为33%,其冲击韧性和硬度分别为47J/cm2和HB 219。此时残余奥氏体含量为15.76%,贝氏体孕育期最短,TRIP效应最明显。
The mechanical properties of the 27SiMn steel such as tensile, impact and hardness, as well as microstructure observation, XRD and SEM were used to analyze the mechanical properties of 27SiMn steel. When the quenching temperature was 770 ~ 830 ℃, isothermal temperature was 360 ~ 420 ℃ and isothermal time was 10 ~ 90min, Microstructure and mechanical properties of the law of change. The results showed that the best comprehensive properties were obtained when the temperature was held at 790 ℃ for 50min and isothermal at 380 ℃ for 20min. After air-cooling to room temperature, the three-phase microstructure of ferrite + bainite + retained austenite was obtained. 225MPa ×%. The tensile strength Rm is 825MPa, the elongation A5 is 33%, the impact toughness and hardness are 47J / cm2 and HB 219, respectively. The retained austenite content was 15.76%, the bainite incubation period was the shortest, and the TRIP effect was the most obvious.