Microstructures and Properties Analysis of Dissimilar Metal Joint in the Friction Stir Welded Copper to Aluminum Alloy

摘要

The paper mainly concentrates on the feasibility of friction stir welding of dissimilar metal of aluminum alloy to copper (T2) and a preliminary analysis of welding parameters influence on the microstructures and properties of joint was carried out. The study show that the thickness of workpiece plays an important role in the welding parameters which could succeed in the friction stir welding of dissimilar metal of copper to aluminum alloy, which was proved to been have a narrow choice. The interfacial region between copper and aluminum in the dissimilar joint was not totally uniformly mixed, but constituted with part of incomplete mixture, complete mixing, dispersion area and mainly the area where the intersection line was obvious. Meantime a kind banded structure with inhomogeneous width was formed. The intermetallic compounds generated during friction stir welding in the interfacial region were mainly Cu9A14 ,A12Cu etc, and its hardness value was high than others.