Abstract:During the process of laser welding for Ti6Al4V alloy, there is large temperature gradient in the weld and the narrow area nearby because of high heat source density, which causes a large gradient of microstructure, properties and residual stress across welded joint. Based on the domestic and foreign literatures, this paper synthetically researches the heterogeneous gradient features of temperature, microstructure, mechanical properties and residual stress of titanium alloy with laser welding. The results show that the studies for large gradient features of welded joint mainly focus on the heterogeneity analysis but not on quantitative analysis and evaluation. Therefore, the method of making a quantitative characterization efficiently and intuitively for the gradient of microstructure, properties and residual stress after welding is very significant for evaluation of overall performance and safety of laser welded joints.