Influence of copper contamination on equilibrium compositions, thermodynamic properties, transport coefficients, and combined diffusion coefficients of high-temperature SF₆ gas

The copper vapor resulting from electrode surfaces in arc devices, such as circuit breakers, may modify the characteristics of arc plasmas. The corresponding properties of plasmas contaminated by the metallic vapor are therefore needed to be determined before setting up physical models. In this paper, the equilibrium compositions, thermodynamic properties, transport coefficients, and combined diffusion coefficients of SF₆-Cu mixtures are calculated at temperatures of 300-30,000 K and a pressure of 0.6 MPa. The influences of copper proportion on such properties are investigated. It is found that a small quantity of copper has no significant influence on the above thermo-physical properties of SF₆-Cu mixtures, while a large quantity of copper can generally change these properties dramatically.