Deformation and microstructural analysis of fiber laser and TIG welding of thin Ti6Al4V sheet by coordinate measurement machine (CMM)
Abstract
This paper reports on a study to compare the mechanical and deformation properties of Ti6Al4V titanium alloy joints between apulsed fiber laser source and a tungsten inert gas (TIG) welding. Ti6Al4V alloy sheets - 0.8 mm thick-deformation modificationswere investigated via a 3D laser scanner integrated to a portable-arm Coordinate Measurement Machine (CMM) and PC-DMISsoftware. Deformation pattern, residual distortions, weld geometry, microstructure and microhardnes properties of the jointsproduced with fiber laser source and tungsten inert gas welding were compared. Compared with the TIG, the welded by fiber laserhas narrow heat affected zone (HAZ), small overall residual distortion, fine microstructure, high Vickers hardness. It can beconcluded that fiber laser welding is more suitable for welding the thin Ti6Al4V titanium alloy plate than TIG welding; due to thesmall beam focus characteristics of fiber lasers enabiling deep penetration welding.