This study investigated deposition parameters for ER70S-6 solid wire deposited using the Wire Arc Additive Manufacturing process. In addition, the microstructure and mechanical properties of deposits fabricated using optimized deposition parameters were compared and analyzed. As the wire feed rate increased, the width and height of the beads tended to increase together. The analysis of effective rectangle area revealed the highest value when the inter-pass overlap was set to 72 % for the first layer and 68 % for subsequent layers. Additionally, the ratio of effective rectangle area tended to in1crease with longer inter-layer dwell times. As a result of the microstructural analysis, the fusion zone exhibited fine grains regardless of the deposited height, but the heat-affected zone was relatively narrow and fine grained as the deposited height increased. It is expected that the bottom heat-affected zone is relatively non-uniform and forms a large microstructure compared to the top due to the repeated thermal cycles occurring in the WAAM process and the heat accumulation occurring in the previous layer. Tensile tests in horizontal and vertical directions showed that the yield strength and ultimate tensile strength were similar, but the elongation was relatively higher in the horizontal direction than in the vertical direction due to the anisotropy of the microstructure that is mainly observed in additive manufacturing.
Park et al. (Wed,) studied this question.