Effect of characteristic substrate parameters on the deposition geometry of CMT additive manufactured Al-6.3%Cu alloy

During the wire and arc additive manufacturing (WAAM) the temperature distribution and geometry of the deposited layers are usually evolving even with the constant deposition parameters. It is thus essential to find out when and how to adjust the processing parameters according to the characteristic parameters of the deposited part, which could be taken as a generalized substrate. In this paper, a modified heat source was employed to establish a tridimensional finite element transient thermal analysis model (FETTA) for the cold metal transfer (CMT) additive manufacturing of Al-6.3%Cu alloy. After validation, this FETTA model was employed to investigate the effect of characteristic substrate parameters, including the length L-x, width W-y, thickness T-z, and initial temperature T-ini, on the minimum temperature (T-min) during the first pass deposition through the Box-Behnken response surface design (BBD). The results showed that L-x had negligible influence on T-min. The T-min model was then established and helped to come up with a new deposition sequence for the deposition of ribbed slabs on a pipe without raising the heat input.