Tensile mechanical behavior of notched 2D-Cf/SiC composites

The influence of notch types on tensile mechanical behavior of 2D-Cf/SiC composite laminates was studied by experimental and numerical methods. Specimens with symmetrical V shape, half round shape and hairline shape notches were tested respectively. The relationship between net stress and tensile deformation closed to the notches was obtained with extensometer. With strain gauges on the surface of notched specimens, the strain variation between notches was obtained. And strain concentration effect was also clearly expressed. In accordance with the law of strain variation, the damage evolution and failure process of the notched specimens were analyzed. By comparing results with that of standard specimens, the failure mechanism of the notched 2D-Cf/SiC composites was discussed, the main influencing factors to the tensile strength were also determined. Furthermore, by finite element analysis (FEA), the strain distribution of notched specimens was simulated. The results indicate that there exists asynchronous damage evolution and failure process on material between notches during tensile process, and the specimen's net tensile strength decreases to some extent with different notch types; the FEA results have good agreement with experimental data.