Microstructural Characterization of Nb-Al Base ODS Alloys

Nb, Al and Y2O3 powders were mechanically alloyed together with 5 wt% stearic acid. The heavy plastic deformation of the powders by mechanical alloying led significant hardening to 970 Hv and the reduced grain size to 10 nm. Nb-Al base ODS alloys consolidated by HIP at 1500 °C and 150 MPa for 0.5 h gave the dual phase of Nb solid solution and Nb3Al compound. The oxide particles are of the hexagonal type YAlO3 (YAH), with the size of 50 nm to 200 nm. The high-temperature ductility at 1200 °C and capability of the grain growth at 2000 °C were confirmed.