Technology Development for Producing Inconel 625 in Aerospace Application Using Wire Arc Additive Manufacturing Process

As the manufacturing sectors are leaning toward additive manufacturing, leaving the traditional methods behind. Wire arc additive manufacturing (WAAM) technique is the growing technique to fabricate the aerospace, defense, and automotive sector components. The major problem associated with the WAAM technique is establishing the process parameters to acquire the defect-free components. In this research work, an attempt has been carried out to establish a wire arc additively manufactured component using Inconel 625 filler. A successful attempt has been made to build the thick slab wall component using Inconel 625. The microstructure analysis was studied in both longitudinal and transverse direction to check the homogeneity. The transverse microstructure at the near substrate region has a cellular structure. The columnar structure is observed in the layer bands between the layers, and the topmost layer revealed equiaxed with a dendritic structure. The longitudinal microstructure varies from a columnar structure in the inter-pass boundaries to fine equiaxed structures between the passes, and at the end, it is an equiaxed structure. Microsegregation in the dendritic core and interdendritic regions was evaluated along with microhardness measurement. The microhardness values along the different layers were increased when taken from bottom to top. Similarly, it increases across the passes due to the formation of an equiaxed dendritic structure. The EBSD investigation was performed to evaluate the manufactured component’s grain size (25.48 ± 61.02 μm), and misorientation angle, low boundary rotation angle (2–5°) and high boundary rotation angle (15–180°). Further, the local dislocation sites were observed through KAM mapping.