The modification of fusion welding techniques for successful joining of silicon carbide-reinforced aluminum alloy composites

This research involved the modification of conventional fusion welding techniques in an effort to successfully join discontinuous silicon carbide particulate-reinforced aluminum alloy composites. Based upon a preliminary evaluation of the weldability of several Al-matrix composites with respect to the gas tungsten arc welding (GTAW) and laser beam welding (LBW) processes, a mechanical assembly was designed, constructed, and modified for use during GTAW. Testing of the assembly involved GTA welding in the butt and spot modes with respect to various specimen geometries and welding parameters. It was concluded that the modified fusion welding technique can be used to successfully join SiC/Al during GTA welding in the spot mode, although further work will be required in order to ensure repeatability. Additionally, it was shown that by controlling high temperature exposure during welding, a fusion zone can be produced in which the basic engineered properties of the composite are retained throughout the weld region.