中低碳铬硅锰马氏体铸钢热处理工艺研究

Technical Research of Heat Treatment for Medium-Low Carbon Cr-Si-Mn Martensitic Cast Steel

摘要：研究了不同热处理工艺对铬硅锰马氏体钢性能的影响。将铸钢件在830--860℃的温度下保温2h；在180～230℃温度下进行等温淬火或者不完全淬火，保温0．5h；在340--430℃的温度区间内，保温1h；然后淬火至室温。最后采用激光器对钢件表面进行扫描式加热。结果表明，中低碳铬硅锰马氏体铸钢在保持一定强度水平的前提下塑韧性明显改善，拉伸强度达1600MPa以上，伸长率为10％以上，平均硬度为HV570～600，明显高于基体硬度HV450，且综合力学性能比传统淬火回火热处理工艺显著提高。

The effect of different heat treatment processes on Cr-Si-Mn martensitic steel was studied. The steel castings were held at 830-860 ℃ for 2 h, isothermally quenched or incompletely quenched at 180-230 ℃ and held for 0.5 h, and kept warm between 340 ℃ and 430 ℃ for 1 h; and quenched to room temperature. At last, the surface of the casting was heated by using of the scanning lasers. The result shows that ductility and toughness of the medium-low carbon steel can be improved obviously with certain strength, and the tensile strength is more than 1 600 MPa, the elongation is more than 10%, and the average hardness is HV 570-600, which is obviously higher than matrix hardness HV 450. Compared with traditional q-tempering heating treatment process, the comprehensive mechanical properties of the casting by the new process are silmificantlv imoroved.