A continuum thermo-inelastic model for damage and healing in self-healing glass materials

• A continuum damage–healing model is developed for the self-healing glass material.
• Distinct nucleation, growth, and healing kinetics of cracks and pores are included.
• Finite element simulations are presented to analyze the effects of various factors.

Self-healing glass, a recent advancement in the class of smart sealing materials, has attracted great attention from both research and industrial communities because of its unique capability of repairing itself at elevated temperatures. However, further development and optimization of this material rely on a more fundamental and thorough understanding of its essential thermo-mechanical response characteristics, which is also pivotal in predicting the coupling and interactions between the nonlinear stress and temperature dependent damage and healing behaviors. In the current study, a continuum three-dimensional thermo-inelastic damage–healing constitutive framework has been developed for the compliant self-healing glass material with different damage mechanisms, i.e. micro-cracks and micro-pores, taken into account. The important feature of the present model is that different physically-driven evolution kinetics have been unified to represent the distinct inelastic, damage, and healing behaviors associated with the mechanical degradation processes. Coupled with the micro-crack and micro-void models reported in the literature, a continuum description of the healing behavior has been established based on the lower-length scale kinetic Monte Carlo simulations to characterize the local thermal–diffusional bond re-formation process across the fracture interface. The proposed formulations are implemented into finite element analyses and the effects of various loading conditions and material properties on the material’s mechanical resistance are investigated.