TA5钛合金激光焊接头组织与力学性能分析OA

This article uses laser self-fusion welding method to achieve welding of 10mm thick TA5 titanium alloy,and explores the relationship between the microstructure and mechanical properties of laser welded joint.It has shown that laser self-welding can achieve high-quality welding of TA5 titanium alloy,with continuous and uniform formation of the weld surface,and no obvious defects such as pores,cracks,and inclusions inside;The microstructure of the base metal consists of small and uniform equiaxed α phase and point like intergranular β phase.The center of the weld seam is mainly composed of coarse β columnar crystals,with small cross distributed needle like martensite inside the crystals;The microstructure of the coarse-grained region is mainly composed of primary block shaped α phase and needle shaped martensite α'phase,while the microstructure of the fine-grained region is mainly composed of equiaxed α phase,a small amount of needle shaped martensite α'phase,and residual β phase;Tensile fracture occurs at the base material far from the weld seam,which is directly related to the formation of needle like martensite,with an average tensile strength of 783MPa;The microhardness of the laser welded joint is the highest at the weld seam,and the overall distribution is saddle shaped.