THERMAL CONDUCTIVITY AND RETENTION CHARACTERISTICS OF COMPOSITES MADE OF BORON CARBIDE AND CARBON FIBERS WITH EXTREMELY HIGH THERMAL CONDUCTIVITY FOR FIRST WALL ARMOUR

摘要

The thermal conductivity of the composite hot-pressed at 2100 degrees C including B4C and carbon fibers with a thermal conductivity of 1100 W/m . K was nearly the same as that of the composite including carbon fibers with a thermal conductivity of 600 W/m . K. This resulted from the higher amount of B diffused into the carbon fibers through the larger interface. The B4C content in the composite can be reduced from 35 to 20 vol% which resulted from the more uniform distribution of B4C by stacking the flat cloth woven of carbon fibers (carbon fiber plain fabrics) than in the composite with 35 vol% B4C including curled carbon fiber plain fabrics. The decrease in the B4C content does not result in the degradation of D (deuterium)-retention characteristics or D-recycling property, but will bring about the decreased amount of the surface layer to be melted under the bombardment of high energy hydrogen ions such as disruptions because of higher thermal conduction of the composite. [References: 3]