Debonding of particle/matrix interfaces can significantly affect the macroscopic behavior of composite material. We have used a nonlinear cohesive law for particle/matrix interfaces to study interface debonding and its effect on particulate composite materials subject to uniaxial tension. The dilute solution shows that, at a fixed particle volume fraction, small particles lead to hardening behavior of the composite while large particles yield softening behavior. Interface debonding of large particles is unstable since the interface opening (and sliding) displacement(s) may have a sudden jump as the applied strain increases, which is called the catastrophic debonding. A simple estimate is given for the critical particle radius that separates the hardening and softening behavior of the composite.
This research was supported by the US Department of Energy and the US Department of Defense/Office of Land Warfare and Munitions under the Joint DoD/DOE Munitions Technology Development Program, the ASCI Center for Simulation of Advanced Rockets at the University of Illinois supported by US Department of Energy through the University of California under subcontract B523819, and ONR Composites for Marine Structures Program (Grants N00014-01-1-0205, Program Manager Dr. Y.D.S. Rajapakse).
- Interface debonding
- Size effect
- Particulate composites
- Constitutive equation