Thermal Analysis of Micro Plasma Wire Arc Additive Manufacturing Deposition Process

Additive manufacturing (AM) is rapidly developing with emerging technology of wire arc additive manufacturing (WAAM) process due to its ability to manufacture large components and high deposition rate. However, WAAM faces mechanical properties problems like porosity, distortion, and strength due to the large heat affected zone (HAZ) from commonly used heat sources such as metal inert gas (MIG) and tungsten inert gas (TIG). Utilization of micro plasma as the heat source should reduce this problem since it has a smaller heat source diameter. Therefore, this study investigates the thermal distribution of micro plasma wire arc additive manufacturing (MPWAAM) by developing a finite element method (FEM) model. This paper focuses on the fabrication of single-layer multitrack deposition and tool path planning of multi-layer multitrack depositions by MPWAAM process. The melt pool size and peak temperature are mainly governed by heat input per unit travel speed of the worktable, with current and voltage being the significant factors. Besides, tool path planning strategy influences the properties and quality of the final product, where parallel tool path design with longer interlayer cooling time minimized part distortion and residual stresses.