棒状共晶体, 纤维夹杂, 桥联应力, 桥联增韧, 尺度效应

According to the microstrcture characteristics of composite ceramic with eutectic interphase, considering the micro slipping on the boundaries of eutectic rods, the bridging stress of eutectic rod was determined. Considering the random orientation of the eutectic rods, the bridging load of eutectic rods was computed by the bridging stress. The bridging load can make crack closure and reduce the stress concentration of the crack tip, the energy dissipative value of the bridging load was obtained. Based on the relationship between fracture toughness and energy dissipation, the bridging toughening result of the eutectic rod and its size dependence were analyzed.The results show that as the diameter of fiber inclusion increases,the bridging toughening value may lessen,

especially when the diameter is in nanometer scale, the size dependence can be more apparent.

eutectic rod, fiber inclusion, bridging stress, bridging toughening, size dependence