Effect of Quenching Temperature on the Microstructure and Compression Behavior of U-2.5Nb Alloy

The compression behavior of U-2.5wt%Nb (U-2.5Nb) alloy with different heat treatment condition was investigated. The microstructure and phase composition were analyzed by OM, XRD and SEM. Results show that the microstructure and phase composition are closely related to the quenching temperature. With the quenching temperature decreased from 800℃ to 620℃, the nb-containing supersaturation monoclinic evolved into α+γ₂ two-phase. The yield strength decreased with decreasing quenching temperature, while the ductility increased significantly. The 655℃ quenched specimen exhibited the lowest yield strength, which may be related to the considerable content of α″ phase obtained by quenching of γ₁ phase.