%0 Journal Article %T 聚酰亚胺改性C/C复合材料的制备及性能
Preparation and properties of polyimide modified C/C composites %A 耿真真 %A 李红 %A 杨敏 %A 任慕苏 %A 孙晋良 %J 复合材料学报 %D 2019 %R 10.13801/j.cnki.fhclxb.20180428.004 %X 采用针刺成型、化学气相渗透(CVI)、真空浸渍及固化成型工艺制备了C/C-聚酰亚胺(C/C-PI)复合材料,研究了这种新型防热结构材料的弯曲性能、导热性能及热膨胀性能。结果表明:C/C-PI复合材料XY向和Z向弯曲强度分别为120.75 MPa和40.33 MPa,较C/C复合材料分别提高了17.92%和20.57%,表现出更优异的弯曲性能;C/C-PI复合材料热导率随温度变化不显著,XY向和Z向热导率均在150℃达到最大值,分别为29.88 W(m·℃)-1和9.93 W(m·℃)-1,较C/C复合材料分别降低了47.02%和56.12%;随温度升高,C/C-PI复合材料的线膨胀系数呈线性缓慢增长,数值保持低于4×10-6 K-1,尤其XY向较Z向具有更低的线膨胀系数,可满足热结构件尺寸稳定性的使用需求。 Polyimide modified C/C (C/C-PI) composites were fabricated by needling technology, chemical vapor infiltration (CVI), vacuum impregnation and curing process. The flexural properties, heat conducting properties and thermal expansion properties of C/C-PI composites were investigated. The results indicate that C/C-PI composites show a better flexural strength of 120.75 MPa in XY direction and 40.33 MPa in Z direction which are 17.92% and 20.57% higher than C/C composite. The thermal conductivities of C/C-PI composites do not change significantly with temperature, and reach the maximum values of 29.88 W(m·℃)-1 in XY direction and 9.93 W(m·℃)-1 in Z direction, which are 47.02% and 56.12% lower than C/C composites, respectively. As the test temperature continues to rise, the thermal conductivities of C/C-PI and C/C composites are decreasing gradually. The coefficients of linear expansion of C/C-PI composites increase linearly with the increase of temperature and the values maintain under 4×10-6 K-1. In particularly, C/C-PI composites have a lower linear expansion coefficient in XY direction in comparison with Z direction, which can meet the requirement of dimension stability of thermal structure parts. 国家重点研发计划(2016YFE0111200 %K 聚酰亚胺 %K C/C %K 弯曲强度 %K 热导率 %K 线膨胀系数
polyimide %K C/C %K flexural strength %K thermal conductivity %K linear expansion coefficient %U http://fhclxb.buaa.edu.cn/CN/abstract/abstract14339.shtml