热处理对选区激光熔化成形AlSi10Mg合金显微组织及力学性能的影响  

Effects of heat treatment on microstructures and mechanical properties of AlSi10Mg alloy produced by selective laser melting

作　　者：余开斌[1] 刘允中[1] 杨长毅 YU Kaibin;LIU Yunzhong;YANG Changyi(National Engineering Research Center of Near-net-shape Forming Technology for Metallic Materials,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]华南理工大学国家金属材料近净成形工程技术中心,广州510640

出　　处：《粉末冶金材料科学与工程》2018年第3期298-305,共8页Materials Science and Engineering of Powder Metallurgy

基　　金：国家重点研发计划资助项目(2017YFB0305800);广东省科技计划资助项目(2014B010129002;2016B090913001)

摘　　要：采用选区激光熔化成形法制备Al Si10Mg合金,然后分别进行退火、固溶以及T6处理,研究热处理工艺对合金显微组织与力学性能的影响,优化其热处理工艺。结果表明:选区激光熔化成形Al Si10Mg合金的物相主要为α-Al基体和共晶Si。共晶体组织[α-Al+单质Si]在α-Al基体上呈连续网络状分布。XOY和XOZ截面的组织均有粗晶区、细晶区和热影响区。经退火处理后,连续网络状分布的共晶Si发生部分溶解和断裂,合金的强度降低,但硬度略微升高。经T6处理后,共晶体呈规则几何形状零散地镶嵌在α-Al基体上,合金的抗拉强度下降,但屈服强度略有提升,塑性明显增强。综合比较,T6处理更适合作为选区激光熔化成形Al Si10Mg合金的后续热处理。AlSi10Mg alloy was prepared by selective laser melting(SLM)process,and then treated by annealing,solid solution and T6 treatment,respectively.The effects of heat treatment on microstructures and mechanical properties of AlSi10Mg alloy produced by SLM were investigated in order to improve heat treatment process of the alloy.The results show that the phases in as-built AlSi10Mg SLM products areα-Al matrix and eutectic Si.The eutectic structure[α-Al+Si]is continuous network distribution on the matrix ofα-Al.The sections of both XOY and XOZ have coarse grain,fine crystal and heat affected zones.After annealing treatment,the eutectic Si network is partial dissolution and fracture,the strength decreases and the hardness increases slightly.While after T6 treatment,the eutectic Si appears with scattered and regular geometry inlays in theα-Al matrix,the tensile strength of the alloy decreases,yield strength slightly increases,and ductility significantly increases.In a comprehensive comparison with respect to strength and ductility,the T6 treatment is more suitable for the AlSi10Mg SLM products.

关 键 词：选区激光熔化 AlSi10Mg合金 热处理 显微组织 力学性能 

分 类 号：TG164.4[金属学及工艺—热处理]