Smoothed particle hydrodynamics simulation of SiC _f /SiC composite scratching mechanism

The SiC fiber-reinforced SiC matrix (SiC f /SiC) composite keeps the high hardness, strength, and high-temperature resistance and overcomes the low fracture toughness of the SiC ceramic due to the reinforcement of the SiC fibers. However, those fiber structures also make the material removal process of SiC f /SiC complex to understand. To reveal the material removal mechanism, a single grit scratching of SiC f /SiC composite model based on smoothed particle hydrodynamics (SPH) was built to discuss the material removal modes of the fiber and matrix with scratching force in different fiber orientations. The results indicate that the matrix is mainly removed in the powdery mode with lateral and median crack propagation. The fibers exhibit shearing, bending, and tension fracture in the transverse and normal directions. In the longitudinal direction, the compression fracture and peel-off modes dominate the material removal process. The maximum and minimum scratching force are in the normal and transverse fiber direction, respectively. The SPH simulation results are validated by the single grit scratching of the 2D SiC f /SiC composite experiments. This research gives a micro-scale insight into the SiC f /SiC composite removal mechanism and damage modes.