Creep Properties Of Heat-Treated Fe-Al-O Ods Alloy

Three different heat treatment regimens were used to modify the microstructure of Fe-Al-O ODS alloy prepared via powder metallurgy. Creep testing at 60 % of alloy state proof stress revealed the highest time to fracture for the bimodal coarse-grained microstructure of the batch heat-treated at 1200 degrees C for 24 h. Heat treatment at 1100 degrees C did not significantly influence the creep resistance of the alloy at 60 % of proof stress creep loading. However, the highest creep resistance was achieved by the strongest hindering of dislocations motion, which can be achieved by decreasing the grain size and increasing the density of dispersed particles, which was the case of the basic state material. Creep damage occurred in the specimens' whole volume, and it was characterized by the growth and coalescence of intergranular cavities.