激光选区熔化成形TC4合金腐蚀行为  

Corrosion Behaviour of Selective Laser Melted TC4 Alloy

作　　者：杨慧慧 杨晶晶[1] 喻寒琛 王泽敏[1] 曾晓雁[1] YANG Hui-hui;YANG Jing-jing;YU Han-chen;WANG Ze-min;ZENG Xiao-yan(Wuhan National Laboratory for Optoelectronics,Huazhong University of Science and Technology,Wuhan 430074,Chin)

机构地区：[1]华中科技大学武汉光电国家实验室,武汉430074

出　　处：《材料工程》2018年第8期127-133,共7页Journal of Materials Engineering

基　　金：国家重点基础研究发展计划(973计划)项目(613281);中央高校基本科研业务费资助项目(HUST:2016YXZD005)

摘　　要：采用激光选区熔化成形技术(Selective Laser Melting,SLM)制备TC4钛合金试样,观察其显微组织,并用电化学腐蚀实验测试不同成形面以及粗糙度对TC4钛合金耐蚀性能的影响,并与传统轧制态进行对比。结果表明:成形方式、成形面和粗糙度均影响TC4钛合金的耐蚀性能。激光选区熔化成形技术制备的TC4钛合金纵截面由原始柱状β晶粒和与生长方向成±45°针状α′马氏体组成,横截面上的晶粒呈棋盘状。传统轧制态由片状α+β相以及等轴α相组成。传统轧制态的耐腐蚀性要强于SLM成形的试样,且SLM成形的纵截面的耐腐蚀性要强于横截面。表面粗糙度小的试样耐腐蚀性要强于表面粗糙度大的试样。激光选区熔化成形态试样腐蚀表面都出现明显的腐蚀坑,腐蚀形态均为点蚀。TC4 alloy samples were built by selective laser melting（SLM）.The microstructure was observed,and electrochemical measurements were performed to investigate the corrosion resistance of SLMed TC4 alloy in different forming surface and roughness.The traditional rolled sample was introduced as a reference.Results show that processing method,forming surface and roughness act a significant role in influencing the corrosion resistance.The microstructure of SLMed TC4 on vertical section consists of the primitive columnarβgrains filled with a large number of acicularα′martensites oriented at approximately ±45°with building direction.Unlike the typicalα＋βphase of traditional rolled sample,a chessboard pattern is observed on cross-section of SLMed TC4.The electrochemical results suggest that the corrosion resistance of traditional rolled sample is superior to that of SLMed sample.SLMed TC4 sample exhibits a better corrosion resistance on the vertical section,compared with the cross-section.Besides,the SLMed sample with rougher surface exhibits poorer corrosion resistance.Obvious etch pit is found on the surface of SLMed sample and the corrosion morphology is pitting.

关 键 词：增材制造 钛合金 耐蚀性能 极化曲线 

分 类 号：TQ150.1[化学工程—电化学工业]