Interfacial Heterogeneous Microstructure and Subsequent Machinability of 316L/CuSn10 Bimetallic Structure Manufactured by Laser Powder Bed Fusion  

作　　者：Jie Chen Zhongpeng Zheng Di Wang Guijun Bi Yuchao Bai 

机构地区：[1]Institute of Intelligent Manufacturing,Guangdong Academy of Sciences,Guangzhou,510070,China [2]Guangdong Key Laboratory of Modern Control Technology,Guangzhou,510070,China [3]State Key Laboratory of Tribology in Advanced Equipment,Department of Mechanical Engineering,Tsinghua University,Beijing,100084,China [4]School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou,510640,China [5]School of Mechanical Engineering and Automation,Harbin Institute of Technology,Shenzhen,518052,China

出　　处：《Additive Manufacturing Frontiers》2024年第3期100-112,共13页增材制造前沿(英文)

基　　金：supported by Guangdong Basic and Applied Basic Research Foundation(Grant.Nos.2023A1515110594,2024A1515012049);GDA Project of Science and Technology De-velopment(Grant.Nos.2022GDASZH-2022010107,2022GDASZH-2022010108);the China Postdoctoral Science Foundation(Grant.No.2022M711807)。

摘　　要：Additively manufactured bimetallic structures combine the advantages of dissimilar materials and can achieve localized properties through a customized composition distribution.However,additively manufactured parts may still lack the dimensional accuracy and surface integrity essential for precision mechanical assemblies that the post-machining process can address.Therefore,this study aims to systematically investigate the microstructure and machinability of 316L/CuSn10 bimetallic structures fabricated using laser powder bed fusion.The results show that the fusion zone of the bimetallic structure had refined grains of microscale size owing to the mixture of the primary elements of the bimetals,which resulted in the highest microhardness of 3.4 GPa.The difference in microstructure and microhardness between the single-material and fusion zones also causes significant differences in the cutting response during the ultraprecision process.The 316L stainless steel side exhibited the highest cutting force and more severe material accumulation in the chips.The cutting force drops when cutting through the fusion zone,with an observable fracture in the chips and separation of dissimilar materials on the machined grooves,indicating that the heterogeneous properties of additively manufactured 316L/CuSn10 bimetallic structures pose challenges to the improvement of surface quality.The simulation results also showed that stress accumulation occurred in the tool path through the fusion zone owing to the higher yield strength and hardness of stainless steel,indicating that lower cutting speeds and depths of cut are favorable for reducing cutting force and improving surface quality.This study provides deep insight into the microstructure evolution mechanism and a theoretical basis for improving the surface quality of additively manufactured bimetallic structures using an ultraprecision machining process.

关 键 词：Laser powder bed fusion Bimetallic structure Heterogeneous microstructures Ultra-precision machining MACHINABILITY 

分 类 号：TG6[金属学及工艺—金属切削加工及机床]