车轻量化用CrNiMo钢激光成形性能及机理分析

Laser Forming Properties and Mechanism Analysis of CrNiMo Steel for Vehicle Lightweight

车轻量化研究的关键是对其材料性能的开发。选择车轻量化用合金材料作为研究对象,设计了一种激光成形CrNiMo合金材料,同时采用直接激光沉积方法(DLD)与选区激光熔融(SLM)增材进行加工。研究结果表明:DLD与SLM试样都呈现单相BCC的晶体结构特征;试样的温度逐渐提高后,硬度持续降低,CrNiMo合金比热容与热导率都出现了增大的趋势;在车轻量化用CrNiMo合金制备方面,DLD相对SLM表现出更好的原位合金化加工适性。该研究开发的CrNiMo合金钢具有很高的力学性能以及机加工性能,为后续高性能零件的开发设计奠定了很好的理论基础,为实际生产过程提供了相关指导。

The key of vehicle lightweight research is the development of its material properties.A laser forming CrNiMo alloy material for vehicle lightweight was designed.Direct laser deposition(DLD)and selective laser melting(SLM)were used for processing.The results show that both DLD and SLM samples exhibit the crystal structure characteristics of single-phase bcc.After increasing the temperature gradually,the hardness decreased continuously,and the specific heat capacity and thermal conductivity of CrNiMo alloy showed an increasing trend.Compared with SLM,DLD showed better in situ alloying performance in the preparation of CrNiMo alloy for vehicle lightweight.The CrNiMo alloy steel developed in this study has high mechanical properties and machining properties,which lays a good theoretical foundation for the subsequent development and design of high-performance parts,and provides guidance for the actual production process.