New composite composed of boron carbide and carbon fiber with high thermal conductivity for first wall

A new composite was created from B4C powder and carbon fiber by hot-pressing at 1700 degrees C or more. The composite sintered at 1700 degrees C with 20-35 vol% B4C shows a thermal conductivity of 250 W/m . K at 25 degrees C which is slightly lower than the felt type C/C, but its value becomes higher than the C/C at temperatures above 400 degrees C. The composite with 40 at% B shows more controllable recycling properties than B4C, The erosion yield for the composite is about half the yield for graphite at 800 K, After electron beam irradiation in order to test heat resistance no cracks were detected up to 22-23 MW/m(2) leading to a surface temperature of 2500 degrees C.