Abstract: Continuous fiber-reinforced ceramic composites (CFCC) have excellent properties at high temperature, which is a new type of high temperature components in aerospace field, and has entered the actual use stage in recent years. It is of great significance to study the parameter control in the preparation process, the quality of the product and optimization and the characterization of the material properties. Analysis of production methods and material properties of CFCC shows that this material has coarse grain and high attenuation characteristics. So original ultrasonic method was modified to transmission method to get an accurate understanding of the acoustic characteristics of the material. The measurement of sound velocity, sound attenuation and other parameters was carried out by image. And, the coefficient of variation of "sound" and "amplitude gray-scale map" were selected as two indicators to characterize the uniformity of the material. The results show that velocity uniformity caused by density and acoustic attenuation uniformity caused by pore results are consistent, indicating that the uneven density of the material is caused by pore. Finally, control of the material quality could be realized through the control of the porosity in the material.

Key words: CFCC, ultrasonic evaluation, homogeneity of the material, coefficient of variation