Deposition geometrical characteristics of wire arc additive-manufactured AA2219 aluminium alloy with cold metal transfer pulse advance arc mode

Abstract

A cold metal transfer pulse advance (CMT-PA) arc mode was employed in this paper for the wire arc additive manufacturing of Al alloy. The effects of process parameters on deposition surface morphologies and geometrical characteristics were investigated. And a deposition width model was built by the multiple linear regressions. Based on the principle that the volume of the sample is equal to that of filler wire, a deposition height model was simultaneously derived. The results indicate that the disparity between two trends of droplet spreading in horizontal and molten pool tangential direction determines directly the final deposition geometrical characteristics. And two trends would be mainly affected by the heat input and arc force closely related to process parameters. The influences of three factors on the effective width percentage show a trend of first increasing and then decreasing. So, it provides an optimal process window for good deposition forming. The effective width percentage reaches 83% and the machining allowance is only 0.71 mm, which significantly improves material utilization and reduces manufacturing costs. Besides, the error rates of deposition width and height models are less than 4% and 6%, respectively. Two models can facilitate fabricating different size complex parts and make a profit for the actual production.