The aim of this work was to study the effect of two different welding processes and postweld heat treatment on the microstructure and mechanical properties of Ti-6Al-4V castings. Gas tungsten arc welding (GTAW) and electron beam welding (EBW) processes were undertaken in this paper. After welding and heat treatment,  the specimens were characterized using macrostructural and microstructural investigations. In addition to that tensile, Charpy impact toughness and Vickers microhardness tests were also conducted. The joints fabricated by EBW process exhibited better mechanical properties than the GTAW joints. Postweld heat treatment cycle was designed and conducted. The designed postweld heat treatment improved the mechanical properties of both types of the weldments. The enhancement of the mechanical properties of the heat treated joints was correlated to the weld metal microstructures.

Ti-6Al-4V, GTAW, EBW, postweld heat treatment, microstructure, mechanical properties.