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

Abstract

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 thermomechanical 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 reformation process across the fracture interface. The proposed

Micromechanics-based damage model for liquid-assisted healing

“…With further decreasing values to about ηnormalvisc=0.02normal normalmPas, the radius evolution becomes increasingly non-linear due to lower significance of the viscous term in equation (18). The linear dependence of void radius over healing time is similar to the response reported by Xu et al. (2014) using a phenomenological approach.…”

Compliant Glass Seals for SOFC Stacks

“…CTE mismatch-induced mechanical cracks and changes in seal porosity, are described in detail in Appendix A and Reference. 10 The proposed material model was calibrated with experimentally obtained properties and then implemented in finite element (FE) analyses through user-subroutines in the commercial FE code ABAQUS. The mechanical performance of single-and multi-cell SOFC stacks was then examined.…”

A softening-healing law for self-healing quasi-brittle materials: Analyzing with strong discontinuity embedded approach

“…For numerically simulating the damage-healing behavior, based on Continuum Damage Mechanics (CDM), a consistent thermodynamic framework coined Continuum Damage-Healing Mechanics (CDHM) was firstly presented in [24], which considered healing as a kind of "negative damage" and presented a general framework for describing the degradationhealing of composites. Belong to the family of CDHM, more recent methods are presented in these years [25][26][27][28][29] including a version coined Cohesive Zone Damage-Healing model [30,31]. Based on CDHM, in [32] Fracture Process Zone (FPZ) elements and Shape Memory Polymer (SMP) tendon elements are respectively built and prescribed at the damage domain of the self-healing beam, for predicting the long-term mechanical behaviour of SMP reinforced concrete beam, as a recent engineering application.…”