Coupling Residual Stress Field to Enhance the Simulation Accuracy of Crack Propagation and Mechanical Responses of High Entropy Ceramics Reinforced by Graphene and Alumina

High entropy carbide (HEC) has attracted significant attention as a function of its exceptional properties for state-of-art engineering structural as well as functional applications. However, the poor toughness dramatically limited the practical application of HEC. Herein, the effects of graphene (G) and Al₂O₃ on crack propagation and mechanical properties of (HfNbTaTiZr)C were investigated through establishing microstructure model and simulating the mechanical responses employing Voronoi mosaic and Python language. The residual stress field was coupled into the simulation process to take into careful account the significant elastic modulus and thermal expansion coefficient differences between the doping phase and the HEC matrix. It was shown that the coupling of residual stress performed critically on retarding the crack propagation through contribution to the frequency of crack deflection, consequently influencing the mechanical properties of the matrix. Furthermore, it is concluded that the residual compressive stress enhanced the mechanical properties of the composites, while the residual tensile stress deteriorated the mechanical responses of the composites. Besides, it is noted that the coupling of residual stress further enhanced the accuracy of the numerical simulation results. The results presented in this paper constitutes a step forward in developing high-performance HEC composites.