Process parameter determination in wire arc additive manufacturing using parameter gradients and multi-sensor data fusion

Abstract In wire arc additive manufacturing (WAAM), identifying the influence of process parameters on part properties is essential when introducing a new material or machine. Conventional parameter studies, where one parameter set per specimen is used, become experimentally expensive for large parameter spaces. In this study, a gradient-based method for determining the influence of the welding parameters on the weld bead height and width for walls manufactured with an oscillating path strategy is introduced to reduce the experimental effort. This is done using parameter gradients along the length of the weld beads instead of welding specimens with only one parameter combination per specimen. The gradient-based method is validated by comparing the results of a conventional parameter study with a parameter study using the parameter gradients. For this, the wire feed speed, the torch speed, and the oscillation amplitude were systematically varied. Additionally, to be able to record the actual parameters during the parameter study, a multi-sensor data fusion approach on the basis of a programmable logic controller is introduced. The approach enables the synchronous measurement of all recorded process data and shows that the set parameters and the actual values during welding can differ, especially for the wire feed speed. The parameter gradient and the conventional approach show similar results, with a difference in height and width of the weld beads below 5%. The experimental effort is reduced by 66%.