针对汽车轻量化的要求,对汽车用铸钢进行研究.首先进行了成分设计,然后通过实验和软件模拟计算主要分析了Mo,V及Si-Ca对钢力学性能与显微组织的影响,最后获得了能达到较好综合力学性能的铸钢成分.实验结果表明:铸钢中质量分数为0.15%~0.20%的Mo和0.08%~0.10%的V以及RE-Ca进行复合变质处理时,加入质量分数为0.1%的Si-Ca,其综合力学性能达到最佳,其抗拉强度、屈服强度分别为1 306和1 245MPa,伸长率为12.7%. In order to reduce the weight of automobile, the cast steel was researched in this paper.First, the composition design was carried out, and then the effects of Mo, V and Si-Ca on the mechanical properties and microstructure of steel were analyzed mainly through the experiment and software simulation. Finally, The results show that when the mass fraction of Mo in the cast steel is 0.15% ~ 0.20% and V and RE-Ca of 0.08% ~ 0.10% in the cast steel are compound metamorphic treatment, The mechanical properties of Si-Ca with the mass fraction of 0.1% are optimized. The tensile strength and yield strength of Si-Ca are 1 306 and 1 245MPa respectively, and the elongation is 12.7%.