Effect of high-energy attrition milling and La2O3 content on the microstructure of Mo-La2O3 composite powders

Abstract Mo-La2O3 composites are potential high-temperature materials for future technology devices operating at temperatures above 1300 °C because of their excellent thermal stability, high mechanical properties and good creep resistance. In this study, we focused on the preparation of Mo-matrix/lanthanum oxide (La2O3) composite powders using high-energy attrition milling. The effects of rotational milling speed (350 and 800 rpm) and La2O3 content (2.5 and 10 vol. %) on the microstructural evolution, phase composition, morphology, and distribution of the second phase in the produced composite Mo-La2O3 powders were investigated in details. The results show that the most interesting composite powder was Mo-10 vol.% La2O3 produced using a rotational speed of 800 rpm, which exhibited better distribution, smaller particle size and higher amount of ceramic phase introduced in the interiors of the Mo grains.