Second Phase Modification and Strengthening Mechanism of Ceo2 Doped Molybdenum Alloy

Abstract

The morphology and size of secondary phase impact greatly on the strengthening effect of the alloys. In this work, a novel nanostructuring strategy is developed to modify the feature of secondary phase of CeO2, and the corresponding influence of particle shape and size on the microstructure and property of the Mo alloy was clarified. It is found that spherical particles with a small size below 205 nm have preferred strengthening effect due to the dominant intragranular distribution of the secondary phases with greater dislocation pinning. The corresponding yield strength can be enhanced about 54.6% compared with pure Mo when the particle size of CeO2 nanospheres is 120 nm. Meanwhile, with similar size (around 110 nm), spherical CeO2 particles exhibit better strengthening effect than the one reinforced by one-dimensional rod-like secondary phase (30.6%).

Keywords: Mo-based alloys, Secondary phase, Cerium oxide, dispersion strengthening