Study on the Adaptation of Self-healing Microcapsules to Matrix Mechanical Properties Based on Extended Finite Element Method

Microcapsule self-healing resin mineral composites,a type of self-healing intelligent material,have found widespread use. The timely release of healing agents from microcapsules to repair microcracks generated in the matrix is crucial for ensuring self-healing performance. Based on the extended finite element method combined with the cohesive force model,the effects of the mechanical properties ratio between microcapsules and epoxy resin matrix and the interface properties on the crack growth path and microcapsules’crackability under different bias cracks were analyzed in this work. Our findings reveal that:(i)crack propagation paths primarily depend on the fracture property ratio between the microcapsule and matrix,with elastic properties playing a less significant role;(ii)given sufficient adhesive strength at the interface,the fracture strength ratio of the microcapsule to the substrate is the main factor influencing microcapsule cracking relative to the fracture toughness ratio; (iii)a larger crack offset distance makes crack deflection easier and microcapsule cracking more difficult;(iv)the existence of interfacial defects is conducive to the formation of interfacial cracks,which is not conducive to the cracking of microcapsules. These findings offer a theoretical basis for applying self-healing materials in engineering contexts. © 2024 Cailiao Daobaoshe/ Materials Review. All rights reserved.