Post heat treatment optimization of cold spray additive manufactured Inconel 718

The cold spray technique has recently emerged as an additive manufacturing method for producing free-standing parts, in addition to its use in repair and coating applications. Manufacturing relatively hard alloys such as Inconel 718 remains challenging and requires careful optimization of process parameters and post-heat treatment (HT) conditions. This work investigates the optimal post-heat treatment procedure for cold-sprayed Inconel 718 parts, focusing on both temperature and duration of the heat treatment process. Cold-sprayed parts are initially heat-treated at 968°C, 1066°C, and 1200°C for 1 hour, followed by a conventional aging procedure. Results indicate that heat treatment at 1200°C reduces porosity and enhances ductility in tensile tests. Furthermore, to assess the effect of HT closer to the material's melting point, samples are heat-treated above 1200°C. Further analysis of the HT temperatures reveals that heat treatment at 1260°C yields the lowest porosity values and shows strong potential to meet manufacturing standards.