等温温度对低合金复相钢力学性能的影响

Influence of Austempering Temperature on Mechanical Properties of Low Alloy Dual-phase Steels

研究了质量分数为0.4%C、1.5%Si、1.5%Mn、0.95%Cr、添加微量稀土的试验钢的力学性能,试验钢由真空感应炉熔炼,经扩散退火、等温淬火处理后,利用扫描电子显微镜进行组织观察分析和XRD定量分析。结果表明,试验铸钢经适当的等温淬火处理后,可获得无碳化物析出的奥氏体-贝氏体复相组织,该复相钢残余奥氏体含量约为8%,具有良好力学性能,硬度值为46.5 HRC,冲击韧度值αk=162.843 J/cm2。

Mechanical properties of the medium carbon low alloy tested steel with 0.4% C, 1.5% Si,1.5% Mn, 0.95% Cr and minor rare earth were investigated. Tested steels were meted in vacuum induction furnace. After diffusion annealing and austempering, the microstructure and phases were analyzed by scanning electron microscope and XRD. The results show that the sample can obtain austenite-bainitic microstructure without carbide precipitation through a proper austemper treatment. The fraction of the remained austenite is about 8%, The tested steel has excellent mechanical properties. Its hardness and impact toughness are HRC46.5 and 162.843 J/cm^2 respectively.