The Influence of Magnetic Arc Oscillation on the Deposition Width Variation along the Length of Multi-layer Single-Pass Walls Produced by Wire Arc Additive Manufacturing Process

Abstract

In this work, a wall printer system was developed, and multi-layer single-pass walls of low carbon steel were produced by the Gas Tungsten Arc Welding-based Wire Arc Additive Manufacturing process with and without Magnetic Arc Oscillation. The influence of the longitudinal oscillating movement of the welding arc during the layer deposition process on the wall geometry was evaluated using cross-sectional macrographs from samples removed from the arc striking point, arc extinguishing point, and middle of the wall. The results show that the wall becomes thinner, and the width variation along the wall length decreases when Magnetic Arc Oscillation is applied. The weld penetration also becomes less deep. A physical model based on the arc force and the magnetic force that acts on the weld pool during layer deposition was proposed to explain the influence of Magnetic Arc oscillation on the width variation noted along the wall length. Because of the alternating movement of the welding arc, the plasma jet and molten metal flow change the direction continuously. As a result, the molten metal does not concentrate at the beginning or end of the deposition length, and the width variation problem is minimized.