EFFECTS OF WELDING PARAMETERS ON MICROSTRUCTURE AND MECHANICAL PROPERTIES OF FRICTION WELDED AZ91 MG ALLOY

Abstract

The AZ91T5 Mg alloy was bonded by applying continuous drive friction welding machine. The friction load, time and speed were used as friction welding parameters, and the effects of these parameters on the microstructure and mechanical properties of the welding interface were investigated. Characterization of welding interface microstructure and fractured surfaces of joints was carried out by optical microscopy and scanning electron microscopy. Microstructural investigations revealed that the welding interfaces have a smooth and continues morphology. The micro hardness and shear strength of matrix and the welding interfaces were measured in order to determine the mechanical properties of the joints. The results showed that the welding interfaces have higher hardness than the matrix and the shear strengths of welding interfaces increased with increasing pressure and speed while time has different effect