Finite element analysis of residual stress toughening Al 2 O 3 /TiC/TiB 2 /h-BN@Al 2 O 3 composite ceramic materials

The residual thermal stress of Al 2 O 3 /TiC, Al 2 O 3 /TiC/TiB 2 , and Al 2 O 3 /TiC/TiB 2 /xh-BN@Al 2 O 3 ( x : 5, 10, 15 vol%) composite ceramics during sintering and cooling was studied by the Monte Carlo method and the finite element method to analyze the effect of residual stress on the fracture toughness of the composite ceramic materials after adding h-BN@Al 2 O 3 . The results show that the microstructure of Al 2 O 3 /TiC/TiB 2 / x h-BN@Al 2 O 3 can be accurately simulated by the Monte Carlo method. With the increase of h-BN@Al 2 O 3 content, the maximum residual tensile stress of the composite ceramic material increases, and the maximum residual compressive stress increases first and then tends to be stable. The analysis shows that the residual stress will affect the grain and grain boundary strength of the composite ceramic material, thus affecting the fracture toughness of the composite ceramic material. When the content of h-BN@Al 2 O 3 is 5 vol%, the fracture toughness of the composite ceramic material is improved due to grain refinement and residual stress. Graphical abstract