Contrary to polymer matrix composites, where the reinforcement is introduced in order to increase the strength, the main reason for the manufacturing of c ceramic matrix composites is their damage tolerance (or catastrophic failure preventing ability or fracture toughness). The property of catastrophic failure prevention is achieved by the compliant fiber-matrix interface. The interfacial compliance can be characterized by the increased internal friction, or specific damping capacity.

Other qualities of interest which can be characterized by vibration measurements are the composite density (indication of porosity) and the interlayer fiber orientation. Both properties were extensively investigated in polymer matrix composites, but much less in ceramic matrix ones.

In the work presented here, the possibilities of rapid non-destructive evaluation of the properties mentioned above for Nickalon/SiC composites, by vibration tests is demonstrated. The vibration method chosen for this set of experiments was the IAR (Impact Acoustic Resonance) method.