Isothermal fatigue behaviour of a (90 deg)8 SiC/Ti-15-3 composite at 426 C

The transverse fatigue behavior of a unidirectional SiC/Ti-15-3 composite is characterized at 426 C. The fatigue behavior of this composite along the (0 deg)8 fiber direction and that of unreinforced Ti-15-3 alloy is compared. It is found that the (90 deg)8 composite fatigue life is much shorter than that of the (0 deg)8 composite. The (90 deg)8 fatigue life is much lower than that of the unreinforced Ti-15-3 alloy. Results from 1D model and fractographic evidence for the (90 deg)8 fatigue behavior indicate that the short life of the composite in this orientation is caused by weak fiber-matrix bond strength.