WANG Gang, ZHAO Shike, JIANG Wan

( Shanghai Institute of Ceramics,Chinese Academy of Science,＊Tsinghua University)

Abstract: In this paper, the mechanism of low temperature oxidation of MoSi₂ was reviewed, and several old routes improving the resistance of the low -temperature oxidation were discussed .On these bases, taking into consideration the effect of grain boundary of MoSi₂ on pesting, a novel method has been proposed to design composite microstructure to enhance low -temperature oxidation resistance of MoSi₂ .The network microstructure of the second phase was formed along the“edge” grain boundaries of MoSi₂ matrix .As a result, the path of oxygen diffusion which causes pesting was blocked by the second phase .Meanwhile, thermal shock resistance and conductivity of materials were less effected .The approach has proved to be effective .

Keywords: molybdenum disilicide, low -temperature oxidation, assumption