Thermal shock resistance of graphite and carbon/carbon composites in plasma disruption simulation tests

Carbon based materials have been successfully used as plasma facing materials in tokamaks for several years. The behavior of carbon based materials under high heat flux is a decisive issue for the design of first wall structure. Thermal shock tests of carbon based materials have been performed with a Nd:YAG laser and pulsed Nd-glass laser recently. The carbon based materials used in the experiments were graphite and four kinds of three-directional carbon fiber reinforced carbon composites (3D-C/C), which were produced with different manufacturing processes. The duration of laser pulse was 0.1 ms and 1.0 ms, respectively. The laser energy density deposited on specimens was up to 13.3 MJ/cm2 for single laser pulses. The corresponding value of φ√t was 42.06 kJ/cm1 s 1 2 , where φ is the power density of incident laser (kW/cm2) and t is the duration of the laser pulse (s). The weight loss and crater depth on the specimens and microstructure photographs of radiated specimen surface are given in the paper.