利用选区激光熔化技术制备梯度结构的Ti-6Al-4V合金  

Additive Manufactured Ti-6Al-4V Alloy with Graded Micro-structure by Selective Laser Melting

作　　者：刘世超 雷鹏飞[3] 刘敏 张耕铭[1,2] 陈超 周科朝 Liu Shichao;Lei Pengfei;Liu Min;Zhang Gengming;Chen Chao;Zhou Kechao(Powder Metallurgy Research Institute,Central South University,Changsha 410083,China;State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China;Department of Orthopaedics,Xiangya Hospital,Central South University,Changsha 410083,China)

机构地区：[1]中南大学粉末冶金研究院,湖南长沙410083 [2]中南大学粉末冶金国家重点实验室,湖南长沙410083 [3]中南大学湘雅医院骨科,湖南长沙410083

出　　处：《稀有金属材料与工程》2021年第10期3543-3549,共7页Rare Metal Materials and Engineering

基　　金：National Key R&D Program of China(2018YFB0704100);Key-Area Research and Development Program of Guangdong Province(2019B010943001);Natural Science Foundation of Hunan Province(2018JJ3654);Fund of State Key Laboratory of Powder Metallurgy,Central South University;International Exchange Program of China Postdoctoral Science Foundation。

摘　　要：采用选区激光熔化技术(SLM)制备了梯度Ti-6Al-4V合金。随着样品沉积厚度的逐渐增加,控制激光功率或扫描速率逐步升高或降低,以此研究了梯度结构Ti-6Al-4V合金的相变及结构演变。结果表明:由于选取激光熔化过程中的高冷却速率,SLM制备的Ti-6Al-4V合金的主要组织结构为初始β柱状晶里的针状马氏体。β柱状晶会随着激光功率的增加或扫描速率的降低而增宽。激光功率和扫描速率的变化会引起马氏体择优取向的变动。最后,由于局部不同的能量变化,随样品沉积厚度增加而逐步升高或降低的扫描速率会引发2种不同的空洞缺陷。Graded Ti-6 Al-4 V alloys were produced by selective laser melting(SLM).Regulation of laser power and scanning speed was applied separately on each sample along the building direction.The microstructure transformation and phase transition in the graded Ti-6 Al-4 V were investigated.Results show that due to the rapid cooling rate of the SLM process,the microstructure of Ti-6 Al-4 V is mainly acicularα’martensite in priorβcolumn grains.Theβcolumn grains are enlarged with the increase of laser power or the decrease of scanning speed.The preferential orientation ofα’grains changes due to the variation of laser power and scanning speed.Moreover,the ascending scanning speed or descending scanning speed during the process may lead to two different defects.

关 键 词：增材制造 选区激光熔化 TI-6AL-4V 梯度结构 柱状晶 

分 类 号：TG665[金属学及工艺—金属切削加工及机床] TG146.23[一般工业技术—材料科学与工程]