?IMPACT OF COPPER VAPOUR CONTAMINATION ON ARGON ARCS?

Abstract

A fast, accurate and comprehensive emission spectroscopic set-up has been employed to study the impactof copper
vapour on an Ar-Cu mixture plasma. Temperature profiles in the arc have been determined in the absence ofCu vapour
and then in its presence, using the absolute line intensity method for an Ar spectral line; these profiles have been
compared with temperature profiles derived from relative intensities of Cu I lines. Temperature profiles derived from
relative intensity ofCu I lines have been used to calculate the radial density distribution of copper atoms in the arc. The
following observations have been made from the resulting atomic number densities: (i) the copper vapour concentrates
in the fringes of the arc, with atomic number densities up to 8.6 X 1011 (cm'): and (ii) Cu atomic number densities in the
core of the arc are small.