Improving surface hardness of aluminum 6063 alloy using hardfacing

Abstract The paper discusses a trial made for the development of surface composite on the surface of aluminium alloy. Alumina particles were used as reinforcement material in the Al6063 matrix. The gas tungsten arc welding is used for surface melting and formation of surface composite. Composite layer obtained was found to have improved hardness compared to the base metal. The effect of parameters of gas tungsten arc welding on the formation and characteristics of the composite layer was also studied. Empirical relation for resultant hardness of the surface composite in terms of input parameters and their interactions is also developed. Scanning electron microscopy analysis suggested uniform distribution of alumina into the matrix. Electron dispersive X-ray spectroscopy results confirmed the presence of alumina in the composite layer. Microstructural investigation was done to study the grain structure and refinement resulting from recrystallization as well as presence of alumina particles.