Bend properties and failure mechanism of a carbon/carbon composite with a 3D needle-punched preform at room and high temperatures

作者：Li Dian-sen^*; Yao Qian-qian; Jiang Nan^*; Jiang Lei

来源：New Carbon Materials, 2016, 31(4): 437-444.

DOI：10.1016/S1872-5805(16)60023-9

• 3D needle-punched C/C composites
• High temperature
• Bending properties
• Failure mechanism

A 3D needle-punched C/C composite with a high density was fabricated and its bend properties were investigated at room and high temperatures. Macro-fracture and SEM micrographs were examined to understand the deformation and failure mechanism. Results show that the load-deflection curves below 400 degrees C exhibit a linear elastic and brittle fracture failure, while the curves at temperatures above 500 degrees C show an obvious tough and plastic failure. The bend strength and modulus decrease significantly with increasing temperature due to severe carbon oxidation. Below 500 degrees C, the main damage to the composite is in the form of matrix cracking, 90 degrees fiber/matrix debonding, local twisting and fracture of the 0 degrees fibers. Above 500 degrees C, the oxidation of the composite is significant and the interfacial adhesion between fibers and matrix is decreased significantly.

• 出版日期2016-8
• 单位北京航空航天大学; 北京农学院; 东华大学