Friction Stir Welding of Dissimilar 5xxx to 6xxx Al Alloys: A Review

Abstract

Many engineering applications in aerospace and automotive field require joining of dissimilar 5xxx to 6xxx Al alloys. Dissimilar Al alloy joints are used for industrial applications due to technical & economic reasons. However, due to different metallurgical behaviour & mechanical properties, joining of dissimilar Al alloys presents a number of challenges. Due to high temperature generation most of the fusion welding techniques are not suitable. In addition, other pressure welding techniques such as – Ultrasonic welding, Roll bonding, Diffusion bonding and Friction welding have some limitation. Hence, friction stir welding (FSW) can be considered to be the most suitable method to join dissimilar Al alloys due to solid-state nature of the process. Since invention, friction stir welding has been a matter of research and investigation for years. In its history of two decades, Friction Stir welding was investigated for joining dissimilar Al alloys during the last decade. Most of studies demonstrated that good quality joints between dissimilar Al alloys can be produced by the Friction Stir Welding (FSW) process. The present study is a chronological & critical review of recent studies on joining of dissimilar 5xxx to 6xxx Al alloys by friction stir welding.