Abstract: To investigate the effect of introducing mesophase pitch based carbon fiber (MPCF) on the properties of carbon/carbon-copper(C/C-Cu) composites. Two types of needling preforms were prepared by MPCF and polyacrylonitrile based carbon fiber (PANCF). Two kinds of C/C-Cu composites were prepared by vacuum pressure impregnation after chemical vapor infiltration (CVI). By characterizing the microstructure, thermophysical properties and mechanical properties, the results showed that, comparing with PANCF needle punched preforms, the addition of MPCF could improve the $XY$ thermal conductivity and reduce the linear expansion coefficient of C/C-Cu composite. The bending strength, bending modulus and $Z$ compression strength of C/C-Cu composite increase 20.4%, 32.3% and 27.7%, respectively.

Key words: esophase pitch based carbon fibers, carbon/carbon-copper composites, thermal conductivity, thermal expansion properties, mechanical properties