以萘为基体碳源,Lewis酸为催化剂,通过对芳烃小分子的催化缩聚建立了一种新型原位聚合C/C复合材料的增密方法.分别对两种不同密度的炭纤维增强C/C复合材料预制体进行致密化处理,研究了原位增密次数对材料体积密度、电阻率、弯曲强度和断面形貌的影响.结果表明:经过五次致密化循环,样品密度分别由原来的1.05 g/cm3和1.68 g/cm3提高到1.52 g/cm3和1.83 g/cm3,电阻率由4.44mΩ·cm和0.84mΩ·cm降至1.09 mΩ·cm和0.28 mΩ· cm,弯曲强度由26 MPa和86 MPa增至95 MPa和211 MPa,说明原位聚合增密方法非常有利于快速提高复合材料的密度和其他物理性能,是一种有前途的增密新途径.%A rapid densification approach for the fabrication of C/C composites was developed by in-situ polymerization of naphthalene with a Lewis acid as catalyst in two preforms of 3D braided carbon fiber/pyrocarbon composites with different densities. The effects of cycle time on the fracture morphology, bulk density, electrical resistivity and flexural strength of the C/C composites were investigated. Results showed that the bulk densities of the C/C preforms increased from 1.05 to 1.52 g/cm3 and from 1.68 to 1. 83 g/cm3, their electrical resistivity decreased from 4.44 to 1.09mΩ·cm and 0. 84 to 0.28 mΩ·cm, and their flexural strength increased from 26 to 95MPa and 86 to 211 Mpa respectively after five cycles. In-situ polymerization is a simple, effective, competitive and rapid densification approach for the fabrication of C/C composites.
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