Experimental Investigation into Melt-Layer Erosion of Plasma Facing Materials

This paper describes melt-layer erosion experiments conducted at North Carolina State University. Metallic samples are exposed to a pulsed plasma heat flux produced by an electrothermal plasma gun. Results for aluminum (2042 Al), copper (OFHC Cu), and stainless steel (316 SS) samples are discussed. The electrothermal plasma gun operated at discharge energies between 0.07 and 8.62 kJ. The sample absorbed fluence ranged between 0.09 and 1.93 MJ/m². The net erosion depth of aluminum approached 1 mm at high energies. Following exposure the samples are bisected to reveal the thickness of material resolidified to the surface. A thickness of resolidified material on an aluminum sample in excess of 50 μm is observed.