选区激光熔化碳化钒颗粒强化316L不锈钢的点阵结构及性能  

Structure and Properties of 316L Stainless Steel Lattice Reinforced via Selective Laser Melting Using Vanadium Carbide Particles

作　　者：付旺琪 钱波[1] 刘志远[1] 李博 Fu Wangqi;Qian Bo;Liu Zhiyuan;Li Bo(School of Mechanical and Power Engineering,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学机械与动力工程学院

出　　处：《激光与光电子学进展》2019年第24期147-153,共7页Laser & Optoelectronics Progress

基　　金：国家重点研发计划（2018YFB1105301）;上海市“科技创新行动计划”政府间国际科技合作项目（19110712500）

摘　　要：通过球磨混粉的方式在316L不锈钢3D打印专用粉体表面引入纳米V8C7颗粒,利用选区激光熔化(SLM)技术制备了V8C7/316L复合材料试样及点阵结构件。在优化的SLM工艺参数下获得的复合材料实体件的致密度高达99.4%;在激光熔化-凝固过程中,V8C7通过分解-析出机制生成的VCx增强相成为纳米级形核质点,其在细化奥氏体相晶粒的同时沿奥氏体晶界分布,可以阻止奥氏体晶粒在快速凝固过程中的长大;纳米尺度的VCx增强相及超细的近等轴晶金属基体均有助于大幅提升增材制造V8C7/316L结构的比强度。Herein,V8C7nanoparticles were mixed with 316Lstainless steel powder via ball-milling for selective laser melting(SLM)-assisted three-dimensional(3D)printing.Then,a lattice structural V8C7/316Lcomposite was printed via SLM.Using optimized SLM process parameters,the density of composite solid parts as high as 99.4%was achieved.In addition,during the laser melting-solidification process,VCx reinforcements were generated via the decomposition-precipitation mechanism of V8C7as the nanoscale nucleation sites.Consequently,the dispersed VCxnanoparticles were preferentially distributed along the austenite grain boundaries,thereby further inhibiting the grain-coarsening of austenite during rapid solidification.The nano-VCx reinforcements and the ultrafine metalmatrix grains that were nearly equiaxed,contributed to a significant increase in the specific strength of V8C7/316L lattice structures.

关 键 词：激光技术 选区激光熔化 工艺优化 点阵结构 性能强化机理 

分 类 号：TG115.5[金属学及工艺—物理冶金]