Z-pin增强陶瓷基复合材料拉伸和层间剪切性能

研究了Z-pin横向增强平纹编织陶瓷基复合材料的拉伸和层间剪切性能。炭纤维平纹编织物和炭纤维Z-pin制备的预成型体, 通过化学气相渗透(CVI)工艺制成Z-pin增强平纹编织陶瓷基复合材料。通过单轴拉伸试验及加-卸载试验研究材料拉伸力学性能参数及破坏规律。采用双切口压缩试验测试材料的层间剪切强度。结果表明, Z-pin增强平纹编织陶瓷基复合材料拉伸应力-应变曲线具有非线性特性; Z-pin嵌入降低了平纹编织陶瓷基复合材料的拉伸强度, 显著提高了陶瓷基复合材料层间剪切强度, 使原来单纯层间基体与织物表面的脱离转变为Z-pin的剪切破坏和层间基体与织物的脱离双重破坏机理。

Investigation on tensile and interlaminar shear of plain woven CMC with Z-pin reinforcement

The tensile and interlaminar shear behaviors of ceramic matrix composite(CMC) with Z-pin reinforcement were investigated.A preform consisting of plain woven fabric and Z-pin through thickness reinforcements was prepared.The process of chemical vapor infiltration(CVI) was used to fabricate the ceramic matrix composite with Z-pins.The tests of uniaxial tensile and unloading-reloading were used to investigate the tensile behavior and the fracture mechanisms of the composite.And a double notch shear(DNS) test was used to investigate the interlaminar shear strength and the fracture mechanism of interlaminar shear.The results show that the tensile stress-strain curve of the plain-woven ceramic matrix composite laminate is nonlinear.Z-pin insertion reduces the tensile strength,and greatly improves the interlaminar shear strength(ILSS) and changes the interlaminar fracture mechanism of the ceramic matrix composite.The debonding of the fabric and the matrix of the interlaminar is changed into double fracture mechanisms of Z-pin shear fracture and the debonding of the fabric and the matrix of the interlaminar.