Optimization of mechanical part’s quality based on a manufacturing strategy in WAAM process

Abstract

International audienceWire Arc Additive Manufacturing (WAAM) process recently attracted strong interest within different industrial fields because of its capabilities to produce large metal parts dedicated to aeronautics, automotive or energy domain. In WAAM process, a weld bead is deposed layer by layer by a robot. The weld bead is fed through a wire of which the tip is fused by power generator.The present work proposes a strategy to choose suitable welding process parameters (welding torch path and process parameters) to obtain an optimal topology quality. To do so, a numerical model fortopology simulation of deposited material is firstly used for 2D configuration. The model is based on the resolution of the Young-Laplace equation which allows to modelize the assembly of weld beads(superposition and juxtaposition). Geometrical meta models based on 3D scans of each layer of the manufactured specimens are used as inputs of the topological model.This work aims to find the best positions of the welding torch enabling to satisfy quality requirementsin a manufactured part. The part’s quality is based on the gap between its manufactured topology and the geometry specified in its associated CAD file. Such as in 2D configuration of topology simulation, we consider some quality criteria such as the size of the part, and the planarity of some specific layers. The height and width of the simulated part are those of the CAD geometry. An optimization strategy is to establish a number N of layers and a number M of weld beads per layer reaching the targetedheight and width respectively. Another criteria is also to minimize planarity defect at every K layer(which is smaller than N). A parallelepiped part is used as a test case for this study