The work performed is part of a broader research effort aimed at describing the behavior of a nuclear fuel used in fast neutron reactors. Complex multiphysics phenomena take place in these fuels [1] and previous work has shown that, under certain circumstances, brittle cracks and healing can occur during thermomechanical cycles undergone by the fuel [3]. In this contribution, we propose a new damage-healing model to simulate the behavior of a brittle elastic solid in a strongly coupled thermomechanical context. In this context, the simulated healing phenomenon is similar to contact welding, depending on the thermo-mechanical state and without external material input. Based on the standard material framework, the Helmotz free energy is defined with the introduction of a state variable called "healing reserve", which allows the damage of a material to be restored. The Clausius-Duhem inequality is satisfied on the basis of a careful choice of appropriate evolution laws. The potential of this model to describe the thermo-mechanical behavior of a brittle-elastic material can be demonstrated with applications that reproduce different healing scenario. This model can be implemented in a cohesize zone framework (for instance using Abaqus or other FEM codes). In parallel to CZM, we are also studying the possibility of extending this approach in a non-local context using the phase-field approach such as proposed by [2]. We have seen from the experimental data that crack patterns can be very complex (and 3D) and not easy to capture with CZM. REFERENCES [1] Y. Guerin. Fuel performance of fast spectrum oxide fuel In Comprehensive Nuclear Materials, Elsevier, page547-page578, 2012. [2] C. Miehe, F. Welschinger & M. Hofacker. Thermodynamically consistent phase-field models of fracture : Variational principles and multi-field FE implementations. International Journal for Numerical Methods in Engineering, 2010. [3] M. Temmar, B. Michel, I. Ramiere & N. Favrie. Multi-physics modelling of the pellet-to-cladding gap closure phenomenon for SFR fuel performance codes. Journal of Nuclear Materials, 2020.