Constructing a novel bi-lamellar microstructure in selective laser melted Ti-6Al-4V alloy via electropulsing for improvement of strength and corrosion resistance  

作　　者：Xudong Yan Xiaofeng Xu Yachong Zhou Zhicheng Wu Lai Wei Dayong Zhang 

机构地区：[1]School of Ocean Science and Technology,Dalian University of Technology,Panjin 124221,China [2]Key Laboratory of Automobile Materials,Ministry of Education,and Department of Materials Science and Engineering,Jilin University,Changchun 130025,China

出　　处：《Journal of Materials Science & Technology》2024年第26期37-50,共14页材料科学技术(英文版)

基　　金：supported by the Provincial Key Research and Development Program of Jilin(No.20230201158GX);the National Key Research and Development Program of China(Nos.2020YFB2008300,2020YFB2008303,and 2020YFB2008304);the Shandong Provincial Natural Science Foundation(Grant No.ZR202102220408);the National Natural Science Foundation of China(Grant No.51701080);the Talent Development-Excellent Young Talents Fund Project,China(Grant No.20190103053JH).

摘　　要：Traditional heat treatments may cause deterioration in the yield strength and corrosion resistance of the selective laser-melted(SLM)Ti-6Al-4V alloy due to the coarsening ofαlath and alloy element partitioning(AEP).However,electropulsing has been found to inhibit the growth of primaryαand the process of AEP.It also introduces finerαlath in the transformedβregion and generates a novel bi-lamellar microstructure.This microstructure has minimal element concentration difference between the primaryαand transformedβ.As a result,the transformedβregion exhibits a higher content of Al element and finerαlath,leading to a higher overall yield strength(952 MPa)compared to the heat-treated sample(855 MPa).The novel microstructure induced by electropulsing enhances the polarization resistance,improves the stability and thickness of the passive film,and ultimately enhances the corrosion resistance.Additionally,this technology can be extended to other SLMα+βtitanium alloys to simultaneously improve their mechanical properties and corrosion resistance.

关 键 词：SLM Ti-6Al-4V alloy Alloy element partitioning Mechanical properties Corrosion resistance 

分 类 号：TG1[金属学及工艺—金属学]