Recent Developments and Research Progress on Friction Stir Welding of Titanium Alloys: An Overview

[摘要] Titanium and its alloys are joined by various welding processes. However, Fusion welding of titanium alloys resulted solidification problems like porosity, segregation and columnar grains. The problems occurred in conventional welding processes can be resolved using a solid state welding i.e. friction stir welding. Aluminium and Magnesium alloys were welded by friction stir welding. However alloys used for high temperature applications such as titanium alloys and steels are arduous to weld using friction stir welding process because of tool limitations. Present paper summarises the studies on joining of Titanium alloys using friction stir welding with different tool materials. Selection of tool material and effect of welding conditions on mechanical and microstructure properties of weldments were also reported. Major advantage with friction stir welding is, we can control the welding temperature above or below β-transus temperature by optimizing the process parameters. Stir zone in below beta transus condition consists of bi-modal microstructure and microstructure in above β-transus condition has large prior β- grains and α/β laths present in the grain. Welding experiments conducted below β- transus condition has better mechanical properties than welding at above β-transus condition. Hardness and tensile properties of weldments are correlated with the stir zone microstructure.

[发布机构] Defence Research and Development Laboratory, Telangana; 500058, India^1;Department of Mechatronics Engineering, Kyungsung University, Busan; 48434, Korea, Republic of^2;Department of Mechanical Engineering, Marri Laxman Reddy Institute of Technology and Management, Telangana; 500043, India^3

[效力级别] 机械制造

[关键词] Bi-modal microstructures;Conventional welding process;Microstructure properties;Process parameters;Solid-state welding;Welding conditions;Welding process;Welding temperatures