Ductilizing Mo alloys via nanoparticle-stabilized microstructural hierarchy

Abstract

Swaged Mo-xLa2O3 alloys (x = 0, 0.3, and 0.6 wt.%) were subjected to different annealing temperatures (Ta), in order to demonstrate the Ta-sensitive La2O3 effect on microstructural evolution and tensile ductility. Although coarse La2O3 particles were detrimental to ductility, nanosized La2O3 particles were found to increase the ductility by highly stabilizing the deformation-induced hierarchical microstructures of lamellar elongated grains with low-angle grain boundaries inside. A competition between the two opposite effects derived from the La2O3 addition led to an unexpected x-dependence of ductility upon different Ta.

Keywords

• Mo alloys
• ductility
• nanoparticles
• microstructural hierarchy
• deformation mechanism