Metallurgical aspects of arc-remelted CuCr contact materials

The arc-remelting technique is a newly developed process for manufacturing CuCr contact materials for vacuum switches. The quality of arc-remelted materials depends strongly on the operation parameters of the remelting process. In this work the remelting system, especially the designation of the arc plasma torch is introduced in detail. The dependence of the plasma jet current, the gas flow rate, and the cooling effect on the metallurgical aspects of melted CuCr materials is investigated. It is suggested that, in some respects, the increase of arc current, the decrease of gas flow rate, and the increase of cooling effect will result in a fine grain size.