Process for the production of a composite wire of small diameter, in particular a wire electrode for electro-discharge machining and a wire electrode obtained thereby

摘要

Multilayer wire, for use as the electrode in electro-erosion, is made by heating a basic component (10) comprising a steel rod with an outer sheath of copper, and pressing two heated strips of a copper-zinc-nickel alloy (12a,12b) on to opposite sides, so that they bond to form an outer protective coating. The resulting circular-section blank is then drawn to the required diameter, eg 0.05-0.50 mm. Also claimed is an electrode wire comprising a central steel wire surrounded by inner and outer layers of Cu and Cu-Zn-Ni alloy respectively, the chemical proportions of the outer alloy layer being uniform, particularly through its thickness.