连续碳纤维增强的聚芳醚酮复合材料的层间破坏

用双悬臂梁和端开口弯曲试件分别研究了连续碳纤维增强的聚芳醚酮复合材料(CF/PEK-C)的Ⅰ型和Ⅱ型的层间破坏。CF/PEK-C的Ⅰ型层破坏的线弹性断裂判据G_(Ⅰc)和弹塑性断裂判据J_(Ⅰc)分别为0.69KJ/m~2且与裂纹长度无关。CF/PEK-C的Ⅱ型层间破坏的稳定性,与裂纹和半距之比α/L有关。当α/L小于0.7时,表现为不稳定的Ⅱ型层间破坏的断裂韧性G_(Ⅱc)为1.62KJ/m~2。当α/L大于0.7时,则为稳定的Ⅱ型层间破坏。此时的G_(Ⅱc)与临界点的选择有关。由亚临界点和0.95点法得出的G_(Ⅱc)值分别为1.73和2.74KJ.M~2。

DELAMINATION OF CONTINUOUS CARBON FIBER REINFORCED POLY (PHENYLENE ETHER KETONE)

Mode Ⅰ and Ⅱ delamination of continuous carbon fiber reinforced poly (phenylene ether ketone) were studied by using, respectively, double cantilever beam (DCB) specimens and end notched flexure (ENF) specimens. Mode I fracture criteria based on the linear elastic theory, GIC,and that on the elastic-plastic theory, JIC, were 0.69 and 0.63 kJ/m2, respectively. Both G/c and JIC was independent of the crack length. Stability of Mode Ⅱ delamioation depended on the ratio of crack length to half span α/L. Unstable Mode Ⅱ delamination occured at α/L less than 0.7 and the critical energy release rate for it was 1.62kJ/m2. The critical energy release-rate for stable Mode Ⅱ delamination depended on determination of the critical load at which crack started to grow and ranged from 1.74 to 2.74 kJ/m2.