Numerical and Experimental Investigation on the Self-Healing Potential of Interpenetrating Metal–Ceramic Composites

Abstract

An interpenetrating metal ceramic composite (IMCC) has been investigated regarding the potential as well as the feasibility of self-healing. Triggered by heating, cracks in the damaged composite located mainly in the Al2O3 ceramic or at the interface could be filled and closed by the liquid AlSi10Mg metal alloy. This healing procedure promises to reduce stress concentrations at crack tips and to improve the mechanical properties compared to the predamaged composite. Two different numerical approaches have been introduced to investigate this assumption and the potential of self-healed IMCCs for a best case scenario: 1) A simple 2D model to analyze the reduction of stress concentrations in front of a crack tip within the ceramic due to healing and 2) a 3D model based on CT-scan reconstructed microstructures to study how macroscopic mechanical properties can be restored depending on the amount of predamage. Further, the self-healing approach has been investigated experimentally for the same composite. Despite the fact that experimental self-healing of the investigated IMCC is only moderately feasible so far, the study shows the great potential that can still be exploited in order to extend the service life time of IMCC engineering components.