Finite element simulation of stress distribution and development of C _f/SiC ceramic-matrix composite coated with single layer SiC coating during thermal shock

The distribution and development of the thermal-shock-induced stress in C_f/SiC ceramic-matrix composites with single layer SiC coating is investigated by finite element analysis. The simulation results indicate that the most dangerous position where the failure may occur in the C_f/SiC ceramic-matrix composite coated with single layer SiC coating during thermal shock is at or near the head part of the fibers and the failure may occur abruptly and easily in the initial period of the cooing stage of a thermal cycle. And the stress distribution characteristic of every single fiber is nearly the same with each other, and shows no evident relationship with the orientation of the orthogonal arranged fibers in the two-dimensional C _f/SiC ceramic-matrix composite coated with single layer SiC coating. And at the same time, the possible failure patterns and failure mechanism for the C_f/SiC composite coated with and without single layer SiC coating has also been discussed in detail.