Based upon the microphotographs of the needled ceramic matrix composites(CMCs)

appropriate representative volume elements(RVE) were selected to establish a single-cell model for predicting the elastic properties of needled ceramic matrix composites.The effect of porosities on the elastic properties of matrix and fiber bundles was considered

and the elastic constants of fiber bundles were calculated by mixed rate

then elastic constants of fiber bundles and matrix were taken into the single-cell model.The elastic properties of needled ceramic matrix composites were calculated by the finite element method(FEM) at last.At the same time

the tests for tensile strength and determination of porosities were carried.Through the experiment

the materials' open porosity of 7.33% and closed-cell porosity of 10.67% were acquired.Numerical results of the elastic properties obtained by the proposed method agree well with the experimental results

and the error is 3.1%.