Modeling effects of temperature, laminated structure, flaws and residual stress on fracture toughness of multilayered and particulate ceramic matrix composites

Considering that the ceramic matrix composites are frequently used in high-temperature applications, it is extremely important to analyze their fracture toughness at high temperatures. At present, there are still few systematic experimental and theoretical studies of temperature-dependent fracture toughness of particulate ceramic matrix composites, especially for the laminated composites. In this work, a series of novel theoretical models of the temperature-dependent fracture toughness of multilayered and particulate ceramic matrix com-posites containing different flaws are developed, by using the stress intensity factor method and the high-temperature fracture strength theory. The work considers the effects of internal and surface flaws, laminated structure and thermal residual stresses within particle and laminate, without the need for fitting to predict high-temperature fracture toughness. The predictions of all models show good agreements with measured data without any fitting parameters. This work provides the potentially efficient methods for obtaining high-temperature fracture toughness and fracture strength of both multilayered and particulate composites that uses only the elastic properties and specific heat capacity, avoiding the traditional destructive experiments such as bending test and single edge notched beam methods.