Rotary Friction Welding of Ti-64 Alloy: A Review

Rotary Friction Welding (RFW) is a solid-state joining technique used to weld symmetrical and circular components. The joining process is obtained through the rotary motion of two workpieces, one which is stationary and the other rotating while undergoing an axial load. During the welding process, the mechanical energy (rotation) is transformed into heat energy through friction. This results in softening of the materials in the weld interface of both pieces, promoting material mixing through rotation and consolidation through forging. In this review paper, a critical analysis of the weld formation and different microstructures achievable in friction welding of high-temperature material, Ti-64, is provided. The main focus of the paper is the comparison of mechanical properties and microstructure of the weld joint, i.e. tensile strength, microhardness, residual stresses, and microstructure of the weld center.