A study of the copper vapour flux from the anode in a nitrogen arc

Abstract

The paper is a sequel to a previously reported study (see A. Rahal et al., ibid., vol.17, p.1807, 1984) of the transport mechanism of copper from the anode of a low-current atmospheric arc in nitrogen, where it was shown that diffusion was the mechanism involved. Copper vapour diffusion velocities are compared, based on the experimentally determined steady state of the discharge. The copper fluxes are then evaluated together with the component due to ambipolar diffusion which amounts to about 20% of the total flux; the total diffusion flux is found to be 4.5 mu g s^-1. The experimental value of the weight loss from the anode is of the order of 100 mu g s^-1. Evaporation therefore accounts for only 5% of the total loss.