High?Temperature Creep Properties of an Additively Manufactured Y ₂ O ₃ Oxide Dispersion?Strengthened Ni–Cr–Al–Ti ?/?’ Superalloy

The effects of the modification a high-?' Ni-8.5Cr-5.5Al-1Ti (wt.%) model superalloy with 0.5 wt.% Y2O3, manufactured by laser powder-bed fusion, on microstructure and compressive creep resistance were investigated. Compared to base alloy, oxide-dispersion strengthened (ODS) alloy exhibits 8-10 times slower rates at 800 °C, over wide range stresses (35-250 MPa). Two regimes observed: diffusional creep, hypothesized be due grain boundary sliding, dislocation stress exponents n=2 n=5, respectively. A creep-resistance anisotropy was observed. horizontal direction, vertical build direction is characterized lower rates, vertically elongated structure. Nonetheless, ODS alloy’s weakest (horizontal) shows better than non-ODS in its strongest (vertical) despite higher number as-built defects (slag, cracks) alloy. strengthening potential additively nickel-based superalloys thus demonstrated. development successful commercial nickel for additive manufacturing processing however requires further additions grain-boundary elements as oxide dispersoids did not significantly increase strength, since cracking still prevalent This article protected copyright. All rights reserved.