Effect of various factors on the thermal conductivity of carbon materials

Plasma facing materials for fusion devices are required to have the high thermal conductivity, high strength and high fracture toughness. Finegrained graphites and C/C composites were used as the base materials for applications to plasma facing components of fusion devices.The effects of high temperature heat treatment, pressurized graphitization and metal (copper or silver) impregnation on the thermal conductivity of these carbon materials have been investigated. As a result, the thermal conductivity of carbon materials increased due to high temperature heat treatment. Pressurized graphitization increased room temperature thermal conductivity. Copper or silver impregnation into the carbon materials seemed to have a tendency for increasing therml conductivity at different temperatures. However, there were some cases in which the thermal conductivity decreased due to metal impregnation at different temperatures. The reason for this was considered that carbon atoms did not adhesive with copper or silver, especially at room temperature.