Interfacial Behaviors in SiC Fiber Reinforced Titanium Matrix Composites during Thermal Exposure

Abstract

Interfacial behaviors of SiC fiber reinforced titanium matrix composites during thermal exposure were investigated by SEM, EDS and XRD. The effect of C coating was mainly analyzed. The results showed that C coating can be an effective barrier of the diffusion of Si element. And the C coating of SCS-6 SiC reinforced Ti6Al4V will be almost completely consumed after thermal exposure for 25 hours at 925°C. TiC will be found in the interface when the C coating exists. After C coating is completely consumed, there is Ti3SiC2 occurring besides TiC and the interfacial debonding strength is high. However, without the protection of C coating, the fibers will be consumed and their longitudinal tensile strength will be decreased, and this will affect the service performance of the composites.