高导热碳/碳复合材料微观结构及导热性能  

Microstructure and thermal conductivity of high thermal conductivity carbon/carbon composites

作　　者：姚彧敏 李红[1] 刘正启 杨敏[1] 任慕苏[1] 孙晋良[1] YAO Yu-min;LI Hong;LIU Zheng-qi;YANG Min;REN Mu-su;SUN Jin-liang(Research Center of Composite Materials,School of Materials Science and Engineering,Shanghai University,Shanghai 200072,China)

机构地区：[1]上海大学材料科学与工程学院复合材料研究中心,上海200072

出　　处：《材料工程》2020年第11期155-161,共7页Journal of Materials Engineering

基　　金：上海市教育发展基金会和上海市教育委员会“曙光计划”(18SG34);军委科技委基础加强计划重点基础研究项目(2017-JCJQ-ZD-035)。

摘　　要：采用国产沥青基碳纤维与中间相沥青制备多孔碳/碳(C/C)复合材料,通过化学气相渗透法(CVI)与前驱体浸渍裂解法(PIP)复合工艺增密,经不同温度高温热处理(HTT)后制备单向C/C复合材料和两向正交C/C复合材料。利用SEM,XRD对不同温度热处理的材料进行微观结构分析,并结合导热机理,分析材料导热性能。结果表明:2300℃热处理后,高导热C/C复合材料结构致密,单向C/C复合材料X向(平行于碳纤维轴向)、两向正交C/C复合材料X向、Y向表现出优异的导热性能;3000℃热处理后,C/C复合材料石墨片层结构明显,石墨化度提高了18.84%,微晶尺寸增大,导热性能进一步提高。两向正交C/C复合材料X向、Y向导热系数可由单向C/C复合材料X向、Z向导热系数计算推导。Porous carbon/carbon(C/C)composites prepared by pitch-based carbon fiber and mesophase pitch were densified by chemical vapor infiltration(CVI)and precursor impregnation process(PIP).After different heat temperature treatment(HTT),the unidirectional C/C composites and bidirectional C/C composites were obtained.The microstructure of C/C composites was investigated by SEM,XRD,and the thermal conductivity was analyzed based on the thermal conductivity mechanism.The results show that unidirectional C/C composites and bidirectional C/C composites have dense structures and excellent thermal conductivity along the fiber axis.After 3000℃treatment,the structure of graphite flat layers become more distinct and the graphitization degree is increased by 18.84%,leading to higher thermal conductivity.Furthermore,the thermal conductivity in X direction and Y direction of the bidirectional C/C composites can be calculated from that of unidirectional C/C composites in X direction and Z direction.

关 键 词：碳/碳复合材料 微观结构 石墨化度 导热性能 复合材料设计 

分 类 号：TB332[一般工业技术—材料科学与工程]