Research and Progress in Laser Welding of Wrought Aluminum Alloys. I. Laser Welding Processes

TLDR

Laser welding is a critical joining technique for widely used aluminum alloys in automotive and aerospace, with carbon dioxide and Nd:YAG lasers employed, the latter especially in keyhole mode for 5000 and 6000 series alloys. This review aims to elucidate how welding processes affect joint quality and to establish a scientific foundation for reliable production of aluminum alloy joints. It examines laser welding parameters, metallurgical microstructures, common defects, and mechanical properties to explain their impact on weld quality. The review critically discusses recent research and progress in laser welding of wrought aluminum alloys from multiple perspectives.

Abstract

With the wide application of Al alloys in automotive, aerospace and other industries, laser welding has become a critical joining technique for aluminum alloys. In this review, the research and progress in laser welding of wrought Al alloys have been critically discussed from different perspectives. The primary objective of this review is to understand the influence of welding processes on joint quality and to build up the science base of laser welding for the reliable production of Al alloy joints. Two main types of industrial lasers, carbon dioxide (CO2) and neodymium-doped yttrium aluminum garnet (Nd:YAG), are currently applied but special attention is paid to Nd:YAG laser welding of 5000 and 6000 series alloys in the keyhole (deep penetration) mode. In this part of the review, the main laser welding processing parameters including the laser-, process-, and material-related variables and their effects on weld quality are examined. In part II of this article in this journal, the metallurgical microstructures and main defects encountered in laser welding of Al alloys such as porosity, cracking, oxide inclusions, and loss of alloying elements are discussed from the point of view of mechanism of their formation, main influencing factors, and remedy measures. In part II, the main mechanical properties such as hardness, tensile, and fatigue strength and formability are also discussed.