Microstructure of composites consolidated at 1000, 1100 and 1200 C is shown in Fig. 3. It can be seen that fibers without curvature distribute uniformly in the matrix of all the composites. This is attributed to the excellent preform. The straightness of the fibers indicates that the preform is compact without pores; otherwise,the fibers will be pressed to bend at the pores during consolidation.