Effect of post-weld heat treatment on microstructure and properties of Ti-23Al-17Nb alloy laser beam welding joints

The mechanical properties of Ti-23Al-17Nb (mole fraction, %) laser beam welding alloy joint at room temperature are comparable to that of the base materials. However, the strength and ductility of the as-welded joint deteriorate seriously after high temperature circulation. The effect of post-welded heat treatment on the microstructure and mechanical properties of the joint was investigated. The heat treatment was taken at 980 °C for 1.5 h, then furnace cooling and air cooling were performed separately. The results indicate that proper post-welded heat treatment improves the ductility of the joint at high temperature.