Effect of heat treatment variations on the mechanical properties of Inconel 718 selective laser melted specimens

The wide usage of Inconel 718 alloy is based on its fusion weldability and its availability in many different forms including cast, wrought and powder. Thus with the emergence of additive manufacturing (AM) techniques for metals, Inconel 718 is a prime candidate for materials to be considered. Powders that have been developed for powder metallurgy are readily available for use in various AM processes such as selected laser melting (SLM) powder bed. While much research has focused on optimizing the deposition parameters to achieve fully densified specimens, subsequent heat treatments and their effect on the microstructure also need to be understood. This study evaluated the microstructure of SLM specimens of Inconel 718 after various heat treatments and compared the resulting effect on the quasi-static mechanical properties.