| 摘要 |
Wire-electrode for electroerosion cutting, comprising a metal core which is a good conductor of electricity and is coated with a single alloy layer consisting of the electrolytic co-deposition of at least two metals, one of which is a metal having a low melting and vaporisation point, such as zinc. This electrolytic alloy layer is relatively ductile so that the diameter of a wire of approximately 1 mm coated with this layer can be reduced in a proportion which ranges from one third to one tenth of its initial diameter in a single cold drawing operation. Its ductility must preferably be very close to that of the metal core. It may be advantageous if the metal having a low melting and vaporisation point and the other metals of the alloy do not diffuse in the hot state into one another, as occurs with a zinc and nickel alloy for example, and if the contents of the metals of the alloy remain constant over the entire thickness of this layer. According to certain variants, the metallic core has a uniform composition from the centre of the wire to the alloy layer. They are manufactured cold, in two stages: - this electrolytic alloy layer is applied from a single electroplating bath, then - the diameter of the wire is reduced, in one single cold drawing operation, in a proportion which ranges from one third to one tenth of its initial diameter. The composition of the galvanic bath and the electrochemical and electrical parameters of the electroplating stage are chosen to as ensure an even composition throughout the electrolytic alloy layer.
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