Micromechanical modeling cyclic loading/unloading hysteresis loops of 3D needle-punched C/SiC ceramic-matrix composites

In this paper, the 3D needle-punched C/SiC composite was fabricated using the chemical vapor deposition and reactive infiltration method. Four different fiber preforms were formed using the needled-punch technology. The PyC interphase was deposited on the surface of the fibers to increase the toughness of the composite under tensile loading. Cyclic loading/unloading tensile tests were conducted at different peak stresses. A micromechanical hysteresis constitutive relationship was developed considering damage mechanisms of matrix cracking, interface debonding and slip, and fiber’s fracture and pullout. Using the developed hysteresis loops models and damage models, the hysteresis loops of four different types of 3D needle-punched C/SiC composites were predicted for different peak stresses. The hysteresis parameters of unloading residual strain, peak strain, hysteresis loops width, hysteresis loops area, interface slip ratio, and inverse tangent modulus were adopted to characterize the tensile damage evolution inside of composites. Relationship between composite’s hysteresis behavior and microstructure damage evolution is established. It was found that the composite’s hysteresis loops depend on the fiber’s preform and interface properties.