Creep characteristics of MoSi2 based composite materials

Creep resistance and microstructure changes Of two MOSi2 based materials were studied. The first one was MOSi2 with 15 vol.% of SiC and the second one MOSi2 with 15 vol.% of HfO2 particles. Creep tests were realized in 4-point bending mode in ambient air at temperatures 1100-1400 degreesC under a stress of 100 MPa. The microstructure and its response to high temperature load were investigated by TEM using thin foil technique. Comparison of the creep resistance of both materials at each particular testing temperature shows that the performance Of MOSi2-15%HfO2 was about one order of magnitude better than that Of MoSi2-15%SiC.