中文摘要：

研究了添加不同含量La和Ce的5Cr2NiMoVSi热作模具钢的力学性能及耐磨性,分析了试样强度、硬度、塑性、冲击韧度和平均磨损率的变化情况,结果表明,加入适量的La可显著提高5Cr2NiMoVSi钢的力学性能;添加适量的Ce,其耐磨性会得到有效提高。当加入0.2%（质量分数）La和0.2%（质量分数）Ce时,5Cr2NiMoVSi钢的力学性能和耐磨性最好。

英文摘要：

Effect of lanthanum and cerium on mechanical properties and wear resistance of 5Cr2NiMoVSi hot die steel were investigated by analyzing its strength,hsrdness,plasticity,impact toughness and wear rate.The results show that suitable addition of La can significantly improve the mechanical properties of the steel,proper content of Ce can increase wear resistance of the steel effectively,and the optimum addition contents of La and Ce should be 0.2%,separately.