Optimization of Wire Arc Additive Manufacturing Based Cold Metal Transfer arc length and dynamic correction parameters using geometrical and Digital Image Corelation analysis

Abstract

The control of the heat input and the geometrical characteristics of the joint during and after a layer deposition remains the concern of the manufacturers in Wire Arc Additive Manufacturing, despite the existence of all new technologies such as the Cold Metal Transfer process. The understanding of the effect of arc parameters having a remarkable role in the optimization of the layer deposition heat input is essential. In the following work, we will focus on the influence of the combination of the parameters of Cold Metal Transfer arc length and arc dynamics correction on the geometrical and mechanical characteristics of the final weld bead. Experimental and statistical investigations have been carried out on F57 filler metal for the assembly of S235 thin metal sheets by the butt joining method using the universal Cold Metal Transfer mode. The main parameters: (i) Arc length correction and (ii) Dynamic Arc correction have been varied to investigate the effect of the combination of these parameters using surface response from experimental plan methods under Minitab software. Furthermore, mechanical investigation using tensile tests coupled with Digital Image Correlation analysis has been realized. The obtained results show that the variation of arc length correction affects considerably the geometrical and mechanical characteristics of the one-layer deposition. However, the effect of the variation of the dynamic arc correction doesn’t affect the width of the welded bead but more the penetration. In the same way, the optimization of the arc’s length enabled us to control the wall’s width and appearance. In addition, optimizing the arc’s dynamics enabled us to control the right blend between layers. These results contribute to the optimization of the Wire Arc Additive Manufacturing-Cold Metal Transfer process parameters for future applications.