中文摘要：

分析了热解炭的双反射特性和消光现象,对热解炭消光角测量方法的理论基础进行了研究,并对化学气相渗透工艺制备的C/C复合材料中热解炭消光角的实验测量数据进行了解释。结果表明：消光角是材料双反射特性的综合反映;消光图法和四分之一象限光强法得到的消光角理论表达式不同,但消光角的数值总是取决于材料的双反射率比值;热解炭的消光角测量值是材料较大反射面积光学特性的平均,包含了杂原子、缺陷、乱层结构的信息,因而和石墨消光角的含义不同;石墨结构是热解炭织构有序的极限,但热解炭消光角并不受石墨理论消光角数值的限制。

英文摘要：

The bireflectance and extinction properties of pyrocarbon are analyzed. The theoretical basis for the measurement of extinction angles is expounded,and an interpretation is provided for the measured extinction angle values of pyrocarbon in C/C composites prepared by chemical vapor infiltration.The results show that the theoretical expression of extinction angles obtained from the extinction graph method is different from that by the one-quadrant intensity observation method.However,the extinction angle is always determined by the bireflectance ratio of pyrocarbon. The measured value of extinction angle for pyrocarbon is the averaged optical response on a large reflection area which may contain heteroatom content,flaws,and turbostratic stacking of the carbon layer. Therefore,it is different in content from that of graphite. Though the structure of graphite is considered to be the limit of the anisotropic degree of pyrocarbon,the extinction angle of pyrocarbon should not be limited by the theoretical value of extinction angle of graphite.