Interfacial phenomena of cold metal transfer (CMT) welding of zinc coated steel and wrought aluminium

The interfacial microstructures and intermetallic compounds produced by cold metal transfer (CMT) welding of wrought aluminium to zinc coated steel have been investigated. The results showed that the reaction layer mainly consists of FeAl3 phase and the thickness of the layer was decreased to 7-8 mu m owing to the low heat input of the CMT method. And the thin reaction layer guarantees the tensile property of the joint. At last, according to the interface characteristic of the dissimilar metal joint, the interfacial reaction process was described in detail.