Hot-pressed silicon carbide resistance to ITER-relevant thermal shock

Abstract Studies were carried out on the thermally induced erosion of silicon carbide as a result of pulsed infrared laser heating, simulating transient heat loads expected in the ITER tokamak divertor zone (laser pulse duration: ms). The critical parameters of pulsed heating that the material can withstand before the onset of erosion with loss of substance were determined. The experimentally observed damage threshold of hot-pressed silicon carbide under thermal shock of submillisecond duration corresponds to a temperature of about K, while a heat flux factor is about (the sample was initially at room temperature). This result is relevant for surfaces with low roughness ( m, m). An increase in surface roughness leads to a decrease in the resistance of ceramics to pulsed heating. For rough surface ( m, m) critical temperature of about K and heat flux factor of about were obtained. Thus, silicon carbide exhibits excellent resistance to transient heat loads as promising plasma-facing material, especially in the case of reduced surface roughness.