In this study, a temperature field finite element model of the thin-walled Ti6Al4V alloy component fabricated by double-wire tungsten arc welding-based wire arc additive manufacturing was established. Detailed heat propagation of the molten pool and the deposited layer was analysed systematically. The simulated results illustrate that the heat accumulation of the thin-walled Ti6Al4V alloy component becomes evident step by step as the deposition process proceeds. The height of the specified heat affect zone increases gradually, and then stabilises, and the stable value is ∼14 mm. The molten pool influences two deposition layers when it moves. The heat conduction from the thin-walled to the substrate still plays a major role as the layers are deposited.

The macrostructure, microstructure and wear performance of Al cladding fabricated by cold metal transfer (CMT) technique were investigated. The overlaps were formed on both sides of Al cladding using CMT technique with direct current mode. The weld depth and contact angle increased, and the overlap length reduced with an increase of heat input, which can be realized by increasing wire feed speed (WFS) or arc length correction (ALC). The grain size and thickness of heat affected zone increased with an increase of heat input, which resulted from increasing WFS or ALC. Due to the increase of average grain size, the hardness value of the clad Al alloy reduced with the increase of ALC. Besides, wear rate increases with an increase of ALC under the scope of load between 80 and 120 N and time between 10 and 20 min. The grooves are clearer at the wear surfaces with an increase of ALC at the wear surface.