Effect of microstructure on impact toughness of pulsed current GTA welded α-β titanium alloy

The preferred welding process for titanium alloys is frequently gas tungsten arc (GTA) welding due to its comparatively easier applicability and better economy. In the case of gas tungsten arc welding, the pulsed current has been found to be beneficial primarily due to its advantages over the conventional continuous current process. Design of Experiments concept has been used to optimize the experimental conditions. Grain size has profound influence on impact toughness. However, impact toughness is inversely related to grain size. Boundaries of primary alpha grains were observed to be preferential sites for crack nucleation and provide easy path for fracture propagation. (c) 2007 Elsevier B.V. All rights reserved.