抄録
The SiC/Al graded composite was fabricated by powder metallurgy processing and its fatigue crack growth behavior was studied. Fatigue crack growth was in direction of from 5% to 30%SiC layers under sinusoidal wave-form. The retardation of fatigue crack growth was found when crack propagated from low volume fraction of SiC to high volume fraction of SiC. The crack deflection and branching at interfaces were observed, which decreased crack growth rates. In view of crack tip driving force, the plasticity mismatch between the lavers shielded crack tip driving force, i.e., decreased the effective J-integral at the tip of the crack as the plastic zone of the crack tip spread across the interface from the weaker material into the stronger material.
