Formation of Carbon-Carbon Composite Material Thermal Conductivity Standards

Carbon material thermal conductivity is an important factor for providing thermal shock resistance. The effect of production factors on the reproducibility of thermal conductivity values during manufacture of three-dimensional reinforced high-density carbon-carbon composite is considered. An average level of thermal conductivity applies to more than 82% of workpieces. From 4.6 to 12.5% of workpieces have thermal conductivity not less than 44 and not more than 70 W/(m center dot K). It is established that a change in carbon fiber treatment temperature from 1600 to 2400A degrees C may lead to an increase in materials thermal conductivity by 0.21 W/(m center dot K) for each 100A degrees C. Adifference in framework structure may change average thermal conductivity within the limits of 3 W/(m center dot K). Variation of material apparent density from 1.89 to 1.98 g/cm(3) gives a change in thermal conductivity by 1.1 W/(m center dot K) for each +0.1 g/cm(3). A connection is established for a carbon-carbon composite of electrical conductivity rho and thermal conductivity lambda, corresponding in form to the Weidemann-Franz rule lambda rho = const.