Effect of Intermetallic Compound Formation in Friction Welded Al Alloy Rods

This study was carried out to evaluate the development of microstructures and mechanical properties on friction welded dissimilar materials with a light weight. For this work, Al6063 and Duralumin alloys with a shape of rod were selected as experimental materials, and friction welding was performed under conditions with a rotation speed of 2,000 RPM, a friction load of 12 kgf/cm2 and an upset force of 25 kgf/cm2, respectively. After welding, the microstructural analysis such as the grain boundary characteristic distributions and the formation of intermetallic compounds was analyzed by electron back-scattering diffraction method and transmission electron microscopy, respectively. In addition, the evaluation of mechanical properties on welded materials was conducted by Vickers microhardness and tensile test. As a result, applying the friction welding led to the significant grain refinement from 50 μm in base material to 2 μm in welded zone, respectively. In case of mechanical properties, Vickers micro-hardness and tensile strength of the welded material occupied 81% and 96% in fraction relative to the base material, respectively, which was attributable to the formation and growth of intermetallic compounds during the welding.