Mechanical Anisotropy and Failure Analysis of Inconel 625 Parts Manufactured Using Wire and Arc Additive Manufacturing (WAAM)

This paper discusses the mechanical failure analysis of Inconel 625 parts fabricated through the Wire and Arc Additive Manufacturing (WAAM) process. Three additive structures were manufactured with three inter-pass layer temperatures (IPT), such as 100, 200, and 300 °C. The tensile specimens were extracted from the additive structure in three principal orientations to evaluate the failure behavior concerning the deposition layer longitudinal (IN625-L), transversal (IN625-T), and diagonal orientations (IN625-D). Grain morphology and grain size varied with different inter-pass layer temperatures. An electromechanical tensile testing machine was used to conduct standardized testing to evaluate the tensile properties. The tensile curves were plotted to describe the tensile strength of the components in three orientations. The mechanical anisotropy and failure behavior of different orientations were defined with the grain boundaries and grain size. Compared to the other two orientations, IN625-D has a higher tensile strength. Because of their distinct orientations, the IN625-L and IN625-T specimens contain more elongated grains, and the IN625-D specimen has more grain boundaries. The strength obtained from grain boundaries is more significant than individual grains.