Preparation and Performance of MoSi2 Based Composites Reinforced by Multi-phases

MoSi2 based composites reinforced by multi-phases were prepared by the hot pressure sintering technique.Influence of the multi-phases number and content on the mechanical properties of the composites were studied,and strengthening and toughening mechanism was investigated.The results indicate that properties of the composites reinforced by multi-phases are better than those reinforced by single phase,those reinforced by two phases are better than those reinforced by three phases,and 5%SiC+5%Nb+MoSi2 composites possess the best comprehensive properties among all the test composites.The strengthening mechanism of the composites reinforced by multi-phases is the corporation of dispersion strengthening and grain refining and the toughening mode may be the integration of phase transition,microcrack,crack deflection and grain refining.