Simultaneous improvement of the strength and fracture toughness of MgO-Al2O3-SiO2 glass/Mo composites by the microdispersion of flaky Mo particles

Abstract

The effect of shape and volume percent of Mo particles on theflexural strength and fracture toughness of MgO-Al₂O₃-SiO₂(MAS) glass/Mo composites was investigated. The flexural strengthand fracture toughness of composites depends heavily on Mo particleshapes, and there is greater improvement in composites reinforcedwith flaky rather than massive Mo particles. In the compositesreinforced with flaky Mo particles, fracture toughness increases withvolume percent of Mo and, at 50 vol% Mo, is 11.6 MPa√m,which is approximately 6.7 times higher than that of the matrix. Increases in fracture toughness of composites reinforced with flakyMo particles is greater than with SiC whiskers, SiC platelets, SiC particles or ZrO₂ particles. Fabricating composites reinforcedwith flaky Mo particles is an effective toughening technique capableof simultaneously improving the strength and toughness of brittlematerials, such as monolithic Al₂O₃ and MAS glass, by utilizing plastic deformation of ductile phase.