Reactions at phase boundaries in pseudoalloys based on tungsten (molybdenum) and copper

The reaction between tungsten and copper in the presence of nickel under conditions close to those of pseudoalloy formation is characterized by the formation of a two-layer zone in the copper. Next to the tungsten there is a layer of a phase containing W, Ni, and Cu. The reaction between molybdenum and copper under the same conditions is not accompanied by the formation of a new phase. It is possible to activate the reactions at the phase boundaries of such a pseudoalloy without increasing its electrical resistivity by decreasing the amount of nickel added to it and ensuring that the addition is evenly distributed over the surface of the particle of the pseudoalloy's refractory component. The addition of cobalt to a molybdenum-copper pseudoalloy leads to the appearance of layers of a Mo6Co7-base phase at its phase boundaries.