The effects of laser process parameters on the weldability of lap joints between aluminum alloy (AA5052) and magnesium alloy (AZ31B)

Abstract

One of the main issues facing the automotive industries is achieving the weight reduction required to meet the demands for reduced fuel consumption, lower air pollution and improved performance. This has generated considerable interest in substituting standard car body materials with light metal alloys. Consequently the technical and economical need for productive and high quality processes suitable for joining dissimilar metals will be increased in the future automotive industry. Aluminium (Al) and magnesium (Mg) alloys are two of the material options being considered because of their advantages of high strength to weight ratio, good recycle-ability and noise and vibration resistance. With this in mind, a research program has been initiated to address some of the technical and scientific issues associated with joining of selected dissimilar metal combinations (Al-Mg, Al-steel, steel-Mg). This paper presents results of an initial study into the laser weldability and mechanical properties for a particular lap joint between aluminium alloy AA5052 and magnesium alloy AZ31B. The aim was to explore the relationships among the process parameters, the formation of inter-metallic compounds and the final strength in the welds. The study confirmed that many potential issues, such as the formation of defects and inter-metallic compounds, can severely impair joint strength.One of the main issues facing the automotive industries is achieving the weight reduction required to meet the demands for reduced fuel consumption, lower air pollution and improved performance. This has generated considerable interest in substituting standard car body materials with light metal alloys. Consequently the technical and economical need for productive and high quality processes suitable for joining dissimilar metals will be increased in the future automotive industry. Aluminium (Al) and magnesium (Mg) alloys are two of the material options being considered because of their advantages of high strength to weight ratio, good recycle-ability and noise and vibration resistance. With this in mind, a research program has been initiated to address some of the technical and scientific issues associated with joining of selected dissimilar metal combinations (Al-Mg, Al-steel, steel-Mg). This paper presents results of an initial study into the laser weldability and mechanical properties for a particular ...