Characterization of Fatigue Behavior in Cross-Ply Laminate of SCS-6/Ti-15-3 Metal Matrix Composite at Elevated Temperature

A study was conducted to investigate the fatigue behavior of a cross-ply, [0/90]2s, laminate of silicon fiber reinforced titanium matrix composite, SCS-6/Ti-15-3 at an elevated temperature of 427°C. Two sets of tests, at frequencies 0.02 and 2 Hz, were run at different stress levels. Fatigue damage initiation and growth patterns were dependent on the specific test conditions of frequency and stress level. Microscopic analysis of the fatigued specimens revealed matrix failure mechanisms ranging from ductile failure to cleavage fracture. The results of this study showed that temperature and frequency, as well as stress levels, are important design considerations for this composite in fatigue loading applications.