FRACTURE DAMAGE ANALYSIS OF SILICON CARBIDE CERAMIC CYLINDRICAL SHELLS BASED ON STATE-BASED PERIDYNAMICS

Silicon carbide (SiC) ceramic material have excellent mechanical properties and is widely used in various engineering components. However, SiC ceramic is an inherently fragile material that can cause tremendous hazards when brittle fracture occurs. Therefore, accurate prediction of its fracture behavior is extremely important. In order to investigate the fracture damage mechanism of SiC ceramic shells subjected to external loads, this paper firstly obtained the critical energy release rate of SiC ceramic through quasi-static tensile and compression experiments, and an ordinary state-based peridynamic model that is appropriate for tensile and compression damage analysis is established. Then, the numerical simulation of the fracture damage behavior of ceramic shells under linearly increasing external loads is implemented by programming in Fortran language, the correctness of the constructed model is confirmed by comparing the simulation value that is achieved with the theoretical predicted value. At last, the fracture damage propagation evolution process of the shells is revealed in detail. The simulation results show that the initial damage zones originate from the compression fracture of the inner surface of the shell, and uniformly distributed at 90° along the circumferential direction. With the gradual increase of the external loads, the tensile fracture damage zones appear on the external surface of cylinder, and the damage zones on the inner and outer surfaces first extend along the circumferential direction, then slowly propagate to the middle surface of the shell, and penetrate the whole cylinder in the thickness direction. Following that, two mixed zones of tensile-compressive damage appear in the axial direction of the shell, which extend along the axial direction and ultimately divide the shell into four fracture zones. The constructed model can successfully describe the fracture damage evolution process of the SiC ceramic structures under intricate loads, while compensating for the drawbacks of state-based peridynamics in damage analysis.