An investigation of plasma-surface interactions on selected conductors and insulators

Abstract

Damage caused by plasma-surface interactions is of concern in fields involving the use of such plasma devices as particle beam weapons, high power lasers and controlled thermonuclear fusion reactors. Several conductors and non-conductors were exposed to a plasma to study the plasma-surface interaction damage. In one part of the study, the plasma was induced by irradiating the surface of the samples with a Q-switched neodymium laser. Some of the samples were irradiated in air, at atmospheric pressure, and in a vacuum, to compare the difference in the extent of the damage on the same types of samples at different pressures. In the other part of the study, several titanium coated conductors and titanium coated non-conductors were exposed to the plasma of a tokamak. Both the metal conductors in the first part of the study, and the titanium coatings in the second part of the study were damaged by unipolar arcing. Nickel showed less evidence of unipolar arcing damage than any of the other samples studies.