Behavior of low-Z materials during plasma disruption simulated by laser beam

The behaviors of graphite, C/C composites and TiC coatings have been tested under near plasma disruption conditions simulated by intense laser beam. Low-Z materials used in the present experiments were G3 and ISO-880U graphite, three kinds of 3D carbon fiber reinforced carbon composites (3D-C/C) and CVD TiC coatings on Mo and G3 graphite. The plasma disruption simulation was carried out with a Nd:YAG laser. The duration of the laser pulse was 0.1 ms while the incident laser energy density on the specimens was up to 1.89 MJ/m2 for a single laser pulse. So the incident laser power density was up to 1.89 MW/cm2 during 0.1 ms and the corresponding value of φt1/2 was up to 18.91 kJ/(cm2 s1/2), where φ is the power density of the 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 surfaces are given in the paper.