石英纤维增强聚酰亚胺透波复合材料的高温热氧老化性能  

High-temperature thermal oxidative aging properties of quartz fiber reinforced polyimide composites

作　　者：鹿海军 刘晓丽 李学山 黄浩 LU Haijun;LIU Xiaoli;LI Xueshan;HUANG Hao(Composite Technology Center,AVIC Beijing Aeronautical Manufacturing Technology Research Institute,Beijing 101300,China;National Key Laboratory of Advanced Composites,AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China)

机构地区：[1]中国航空制造技术研究院复合材料技术中心,北京101300 [2]中国航发北京航空材料研究院先进复合材料重点实验室,北京100095

出　　处：《航空材料学报》2022年第5期127-134,共8页Journal of Aeronautical Materials

摘　　要：通过对石英纤维及其聚酰亚胺复合材料(QW280/AC721)的人工加速热氧老化处理,研究老化对石英纤维及其复合材料结构和性能的影响。结果表明:石英纤维经300℃高温老化后,由于表面浸润剂氧化分解导致其拉伸强度显著降低,150 h后的拉伸强度保持率为44%;聚酰亚胺复合材料中的纤维因有树脂保护作用,复合材料力学性能保持率较高,经300℃老化处理150 h后,模量几乎没有变化,拉伸强度室温和300℃保持率分别在76%和92%以上,弯曲和层间剪切强度保持率均在85%以上。复合材料的高温介电性能稳定,经历300℃热氧老化不同时间(0~150 h)后,在7~18 GHz频段内的介电常数保持在3.5~3.8之间,介电损耗角正切值低于5×10^(−3)。The influences of aging on the structure and properties of quartz fiber and its polyimide composites(QW280/AC721)were studied by the artificial accelerated thermal-oxidative aging experiments.The results show that after aging at 300℃for 150 h,the tensile strength of quartz fiber is significantly reduced with the retention ratio of only 44%,which is ascribed to the oxidation and decomposition of the surface wetting agent of the quartz fiber.However,due to the protective effect of polyimide resin on the fiber,the mechanical properties of the polyimide composites have a high retention rate.After aging at 300℃for 150 h,the modulus of the composites shows no obvious change,the retention ratios of tensile strength at room temperature and at 300℃are above 75%and 91%respectively,and the retention ratios of bending and interlaminar shear strength are both above 85%.The dielectric properties of the composites are stable upon the high temperature treatment.After the thermal-oxidative aging at 300℃for different time periods(0-150 h),the dielectric constant in the frequency band of 7-18 GHz remains in the range of 3.5-3.8,and the dielectric loss tangent is lower than 5×10^(−3).

关 键 词：耐高温 热氧老化 石英纤维 聚酰亚胺复合材料 透波 

分 类 号：TB332[一般工业技术—材料科学与工程]