| Abstract Scope |
This study optimizes the high-energy ball milling and spark plasma sintering (SPS) parameters to improve the microstructure and mechanical properties of IN718 and IN718-GNP composites. Various milling times (1–24 hr) and routes (dry/solution ball milling) were examined, alongside sintering conditions (900°C–1200°C, 5–60 min dwell time, 50 MPa pressure, 100°C/min heating rate). Optimal microstructure and mechanical properties were achieved with 6 hr of dry ball milling route and SPS temperature of 1100°C and 5 min dwell. The microstructure of samples was characterized using XRD, SEM/EDS, and the mechanical properties were evaluated using Vickers indentation and uniaxial tensile testing. GNP-reinforced IN718 sample showcased enhanced hardness, yield strength, and ultimate tensile strength by ~29%, ~43%, and ~8%, respectively, compared to pure IN718 alloy owing to the grain refinement, dislocation strengthening, and solid solution strengthening. These findings underscore the potential of processing IN718-based composites in structural applications. |