Thermal stability and influence of Y2O3 dispersoids on the heat treatment response of an additively manufactured ODS Ni–Cr–Al–Ti γ/γ′ superalloy

The post-processing treatment response of a Y2O3 oxide-dispersion-strengthened (ODS) and γ/γ′-strengthened Ni–8Cr–5.5Al–1Ti (wt.%) model alloy, produced by laser powder bed fusion (L-PBF) is studied. solutionizing at 1260 °C induces significant recrystallization the initial elongated grain microstructure, characteristic L-PBF processing. Grain-boundary pinning dispersoids affects efficiency, leaving behind pockets fine 1–10 μm grains in-between 200–400 large with complex shapes. Y2O3/Y2O2S exhibit excellent coarsening resistance during solutionizing, are stable subsequent aging heat treatments 850 °C. slow cooling from promotes formation secondary tertiary γ′ precipitates, ODS particles located within γ channels. Within timescale isothermal aging, up to ∼1000 h, rate precipitates slightly faster in material. This allows independently optimize volume fraction size for balanced properties. Additionally, capability hot isostatic pressing (HIP) close heal cracks investigated under various consolidation parameters. post-process significantly widen processing window alloy.