激光选区熔化成形316L不锈钢断裂性能的有限元模拟与试验验证  

Finite Element Simulation and Experimental Verification of Fracture Properties of 316L Stainless Steel Formed by Selective Laser Melting

作　　者：谢卓文 蒋玮[1] 金建行 吴浩楠 杨光辉[1] XIE Zhuowen;JIANG Wei;JIN Jianxing;WU Haonan;YANG Guanghui(National Key Laboratory of High Performance Precision Manufacturing,School of Mechanical Engeering,Dalian University of Technology,Dalian 116000,China)

机构地区：[1]大连理工大学机械工程学院,高性能精密制造全国重点实验室,大连116000

出　　处：《机械工程材料》2023年第6期90-95,102,共7页Materials For Mechanical Engineering

基　　金：国家自然科学基金资助项目(51575076)。

摘　　要：采用晶体塑性有限元法和内聚力模型建立考虑激光选区熔化(SLM)成形316L不锈钢显微组织特征的代表体积单元(RVE)模型,基于模拟得到的应力、应变数据模拟了不同体能量密度SLM成形紧凑拉伸试样的断裂过程,得到J积分曲线并与试验结果进行了对比。结果表明:SLM成形316L不锈钢试样在拉伸过程中内部受力不均匀,在改变内聚力单元最大名义应力后,模拟得到不同体能量密度下各试样的真应力-真应变曲线存在差异,更符合试验结果;不同体能量密度SLM成形试样的J积分模拟值与试验值基本相符,均方根误差在4.66~12.88 kJ·m^(-2),使用的RVE模型和模拟方法能够有效地模拟得到SLM成形316L不锈钢的断裂韧度。Representative volume element(RVE)model of 316L stainless steel formed by laser selective melting(SLM)considering the microstructure characteristics was established by crystal plasticity finite element method and cohesion model.Based on the stress and strain datas,the fracture process of the compact tensile specimens formed by SLM with different volume energy densities was simulated,and the J-integral curve was obtained and compared with the experimental results.The results show that the internal stresses of 316L stainless steel specimen formed by SLM were not uniform during tensile deformation.The true stress-true strain curve of specimen under different volume energy densities was different after the maximum nominal stress of cohesion element was changed,which was more consistent with the experimental results.The simulated J-integral values of specimen formed by SLM with different volume energy densities were basically consistent with the experimental values,and the root mean square error was 4.66-12.88 kJ·m^(-2).The RVE model and the simulation method used could effectively simulate the fracture toughness of 316L stainless steel formed by SLM.

关 键 词：激光选区熔化 316L不锈钢 断裂性能 晶体塑性有限元 代表体积单元 

分 类 号：TG142[一般工业技术—材料科学与工程]