| Abstract Scope |
IN718 with high Si-scrap offers cost-saving potential, but microstructure control is vital to prevent micro-segregation and Laves phase formation. To achieve this, a homogenization treatment is employed. In this study, as-cast IN718 containing 0.2 and 0.4 wt.% Si were subjected to experimental investigation at 1100, 1150, and 1175 °C for 12, 36, 60, and 96 hours. A unique characterization and analysis scheme ascertains the extent of solute redistribution in the as-cast and heat-treated alloys. Using an area-grid scan method, around 2000 points were examined, allowing data collection from dendritic and inter-dendritic regions. Composition data were ranked, sorted using WIRS and plotted against solid fractions, generating concentration profiles. Homogenization extent was evaluated by observing changes in delta values, representing the difference between maximum and minimum solute concentrations, as a function of temperature and time. Furthermore, a diffusion-based homogenization model was developed, which predicted the degree of homogenization and Laves phase dissolution. |