Synthesization of CNTs on Pore Surfaces in C/C Composites and Effect of CNTs on Tribological Characteristics
Kiyotaka OBUNAI, Kazuya OKUBO and Toru FUJII
Abstract:The purpose of this study is to stabilize the coefficient of friction of carbon-carbon (C/C) composites through wide environmental temperature range by synthesizing the carbon nanotubes (CNTs) on its surface and inner pore. In this study, conventional CFRP was carbonized at 2,200 with inert atmosphere to fabricate the C/C composites in which char matrix was made from phenolic resin. CNTs were synthesized on the surface and inner pore of fabricated C/C composites by the thermal chemical vapor deposition method. The coefficient of mutual friction and wear amount between two flat specimens were measured at a constant rotational speed under constant applied pressure by using the disc-type test apparatus. The effect of CNT synthesization on the mutual friction coefficient and its dependence on test temperature were discussed. Frictional coefficient was high and also stable when the CNTs were synthesized on surface and inner pore while the test temperature was changed. The wear amount of modified C/C composites was almost same as that of unmodified one. Test results also showed that the variation of friction coefficient of modified C/C composites during frication test was explained by the variation of local volume fraction of matrix of C/C composites. Key Words:C/C composite, Carbon nanotube, CVD, Coefficient of friction