激光成形车用CrNiMo合金钢的组织及成形性能分析

Microstructure and Properties Analysis of CrNiMo Alloy for Car by Laser Deposition

选择车轻量化用合金材料作为研究对象,开发得到CrNiMo合金。依次采用直接激光沉积方法(DLD)与选区激光熔融(SLM)两种增材加工方法实现了CrNiMo试样的原位合金化。研究结果表明:采用DLD和SLM进行增材处理时,获得了接近等原子比的原位合金;持续提高DLD激光功率,试样密度增大,到达1340 W时获得7.48 g/cm^(3)的最大密度值;DLD激光功率在1140 W以上时,制备CrNiMo试样达到电弧熔炼程度;DLD与SLM试样都出现了元素富集的情况,在DLD试样内存在残留的Ni,SLM试样内则存在部分Mo富集现象;在车轻量化用CrNiMo合金的制备方面,DLD相对SLM表现出更好的原位合金化加工适性。

CrNiMo alloy was developed by selecting the alloy material for vehicle lightweight.In situ alloying of CrNiMo samples was achieved by direct laser deposition(DLD)and selective laser melting(SLM).The results show that in situ alloys close to equal atomic ratio are obtained by DLD and SLM additive treatments.The DLD laser power was continuously increased,and the sample density increased.When it reached 1340 W,the maximum value of 7.48 g/cm3 was obtained.Arc melting of CrNiMo samples prepared by DLD with laser power above 1140 W is achieved.Element enrichment occurs in both DLD and SLM samples.Residual Ni exists in DLD samples,while partial Mo enrichment exists in SLM samples.Compared with SLM,DLD showed better in situ alloying performance in the preparation of CrNiMo alloy for vehicle lightweight.