基于SEVNB法对层压陶瓷复合材料断裂韧性的研究

Fracture Toughness of Laminated Ceramic Composites Based on SEVNB Method

采用简单模压工艺制备了Al_(2)0_(3)/铁丝网夹层层压陶瓷复合材料,采用基于飞秒激光的SEVNB法测试了其在不同切口位置的断裂韧性值,分析了切口尖端半径对该材料断裂韧性测试值的影响。结果表明,Al_(2)0_(3)/铁丝网夹层层压陶瓷复合材料表现出近似脆性断裂行为,切口尖端最低点在第4层铁丝网夹层时的断裂韧性值达6.88MPa·m^(1/2),高于在第3层时的5.51 MPa·m^(1/2),略低于介于第3与第4层之间时的7.01 MPa·m^(1/2),且切口尖端半径对该材料断裂韧性测试值影响小。

In this paper,the Al_(2)0_(3)/steel mesh laminated ceramic composite was prepared by simple molding process,using alumina ceramic sheet,steel mesh and epoxy binder as starting materials.SEVNB method based on femtosecond laser was used to test the fracture toughness of this composite at different notch positions.The influence of notch tip radius on the fracture toughness of this composite was analyzed by comparing with the test results of SENB method.Experimental results show that the Al_(2)0_(3)/steel mesh laminates ceramic composite exhibit approximately brittle fracture behavior.The fracture toughness of this composite at the fourtti steel interlayer is 7.01MPa·m^(1/2),which is higher than 5.51 MPa·m^(1/2) at the third interlayer,and slightly lower than the 6.88MPa·m^(1/2) between the third and fourth interlayers.And the radius of notch tip has little effect on the fracture toughness test value of the composite.