Research on the microstructure and properties of weld repairs in TA15 titanium alloy

This paper presents repeated weld repairs of TA15 titanium alloy rolled plates using gas tungsten arc welding with filler metal. The purpose of this work is to examine and quantify the effects of repeated repair cycles of TA15 titanium alloy plates on the microstructure features, elemental distribution, phase composition and mechanical properties. The results demonstrated that sound joints without defects could be obtained after weld repairs. With increasing repair cycles the amount of the acicular α phase in the weld seam increased, the size became larger and the alloy elements were distributed more unevenly between the weld seam and base metal. The hardness and fatigue properties of the joints decreased with increasing repair cycles, especially for the joint after the fourth welding repair.