Finite Element Model Developed for Coupled Chemical-Mechanical-Thermal Contact with Bonding and Debonding
Researchers have developed a finite element formulation that simultaneously models chemical, mechanical, and thermodynamic interactions at the contact interface between deforming bodies. The work extends prior contact theory by Sauer et al. (2022) to incorporate bonding and debonding evolution coupled with thermal and mechanical states. This advance enables more realistic simulation of complex interfacial phenomena such as exothermic bonding reactions, thermal hardening, and simultaneous bonding and debonding.
A new computational framework presented on arXiv introduces a finite element formulation for coupled chemo-mechano-thermodynamical large deformation contact, targeting the simulation of bonding and debonding processes at material interfaces. The approach builds on a six-field contact theory—covering deformation and temperature of two contacting bodies, an interfacial bonding field, and interfacial temperature—where the interfacial temperature is driven by both chemical and mechanical energy dissipation. Several elementary models based on a quadratic contact potential are proposed to capture pressure- and gap-dependent bonding, exothermic reactions, thermal hardening, and thermal expansion. The implementation is monolithic, employing both classical and isogeometric finite element shape functions with implicit time integration, and includes full linearization for Newton-Raphson solution. A notable efficiency feature is that when bonding sites correspond to material points, the bonding variable can be condensed out locally, reducing computational cost. The formulation is validated through multiple challenging numerical examples demonstrating its generality and versatility across a range of coupled interfacial scenarios.
What's missing
As a preprint, this work has not yet undergone formal peer review. The paper does not report computational cost benchmarks or comparisons against experimental data, leaving open questions about real-world validation and scalability to large-scale engineering problems.
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- arXiv physicsCenter
A coupled finite element formulation for chemo-mechano-thermodynamical contact and its application to bonding and debonding
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