Modeling oxidation damage of continuous fiber reinforced ceramic matrix composites  

作　　者：Cheng-Peng Yang Gui-Qiong Jiao Bo Wang 

机构地区：[1]Department of Engineering Mechanics, Northwestern Polytechnical University, 710129 Xi'an, China

出　　处：《Acta Mechanica Sinica》2011年第3期382-388,共7页力学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (90405015)

摘　　要：For fiber reinforced ceramic matrix composites（CMCs）,oxidation of the constituents is a very important damage type for high temperature applications. During the oxidizing process,the pyrolytic carbon interphase gradually recesses from the crack site in the axial direction of the fiber into the interior of the material. Carbon fiber usually presents notch-like or local neck-shrink oxidation phenomenon,causing strength degradation. But,the reason for SiC fiber degradation is the aw growth mechanism on its surface. A micromechanical model based on the above mechanisms was established to simulate the mechanical properties of CMCs after high temperature oxidation. The statistic and shearlag theory were applied and the calculation expressions for retained tensile modulus and strength were deduced,respectively. Meanwhile,the interphase recession and fiber strength degradation were considered. And then,the model was validated by application to a C/SiC composite.For fiber reinforced ceramic matrix composites（CMCs）,oxidation of the constituents is a very important damage type for high temperature applications. During the oxidizing process,the pyrolytic carbon interphase gradually recesses from the crack site in the axial direction of the fiber into the interior of the material. Carbon fiber usually presents notch-like or local neck-shrink oxidation phenomenon,causing strength degradation. But,the reason for SiC fiber degradation is the aw growth mechanism on its surface. A micromechanical model based on the above mechanisms was established to simulate the mechanical properties of CMCs after high temperature oxidation. The statistic and shearlag theory were applied and the calculation expressions for retained tensile modulus and strength were deduced,respectively. Meanwhile,the interphase recession and fiber strength degradation were considered. And then,the model was validated by application to a C/SiC composite.

关 键 词：CMCs- Oxidation- Interface- Mechanical properties - Micromechanical model 

分 类 号：TB332[一般工业技术—材料科学与工程] X503.1[环境科学与工程—环境工程]