Thermal cycling on microstructure and mechanical properties of laser powder bed fusion manufactured IN738LC alloy  

作　　者：Yong Hu Hui-Bin Jia Yong-Qi Hu Cheng Chu Xu Zhang Li-Hua Wang Dong Zhang 

机构地区：[1]School of Material Science and Engineering,Lanzhou University of Technology,Lanzhou,730050,China [2]State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals,Lanzhou University of Technology,Lanzhou,730050,China [3]State Key Laboratory of Nickel and Cobalt Resources Comprehensive Utilization,Jinchang,737100,China

出　　处：《Rare Metals》2024年第12期6649-6672,共24页稀有金属(英文版)

基　　金：financially supported by Gansu Key Research and Development Program(No.22YF7GA156);the Major Science and Technology Project of Gansu Province(No.22ZD6GA008);Hong Liu First-Class Discipline Construction Plan of Lanzhou University of Technology(No.CGZH001)。

摘　　要：This study investigated the impact of thermal cycling effects on the microstructure and mechanical properties of IN738LC alloy manufactured by laser powder bed fusion,considering different volumetric energy densities(VEDs)and interlayer times(ILTs)as part of the experimental parameters.The results show that low VED and long ILT samples displayed superior quality,with an average grain size of 10.97μm and relatively low strain accumulation level.In contrast,samples with high VED and long ILT exhibit increased cracking and porosity,the average grain size is 14.63μm and present higher strain accumulation degree.The nano-primary MC phase within the alloy transformed into a spherical secondary MC phase inside the grain and a polygonal secondary MC phase on the grain boundary.In the low VED and long ILT,the mean equivalent diameter(MED)of MC carbide within the grain and on the grain boundary was 63 and 140 nm,respectively,the tensile strength was 1072±21 MPa.By contrast,for the high VED and long ILT,the MED of MC carbide in the grain and on the grain boundary were 47 and105 nm,respectively,and the tensile strength was794±31 MPa.The tensile strength of high VED and long ILT decreased by 26%compared with low VED and long ILT.

关 键 词：Laser powder bed fusion(L-PBF) IN738LC alloy Thermal cycling MICROSTRUCTURE Mechanical properties 

分 类 号：TG132.3[一般工业技术—材料科学与工程] TG665[金属学及工艺—合金]