Enhanced mechanical properties of molybdenum alloy originating from composite strengthening of Re and CeO2

Abstract

To enhance the mechanical properties of molybdenum alloys at both room and high temperatures, Mo−14Re−1CeO₂ alloy was synthesized using the powder metallurgy method, and the corresponding microstructure and mechanical properties were characterized. The results indicate that the ultimate tensile strength of Mo−14Re−1CeO₂ reaches 657 MPa, with a total elongation of 35.2%, significantly higher than those of pure molybdenum (453 MPa, and 7.01%). Furthermore, the compression strength of Mo−14Re−1CeO₂ at high temperature (1200 °C) achieves 355 MPa, which is still larger than that of pure molybdenum (221 MPa). It is revealed that there is a coherent interface between CeO₂ and the Mo−14Re matrix with CeO₂ particles uniformly distributed in both intergranular and intragranular regions. The improvements in mechanical properties are primarily attributed to the formation of Mo−Re solid solution, grain refinement, and dispersion strengthening effect of CeO₂.