Process for the manufacture of wires with a brass surface, for the purpose of wire electroerosion
AssigneeCharmilles Technologies S.A.
InventorJean Paul Briffod
Life of this patent
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Abstract
Copper wire coated with a layer of zinc is heated to a temperature (T.sub.1) sufficient for the formation of a brass phase .beta., and the temperature is maintained until complete diffusion of the zinc. The thickness of the zinc covering can be chosen in such a way that once the zinc is completely diffused, the wire consists of a brass phase .beta. in its periphery and of copper in its central part. The wire is then heated to a temperature (T.sub.2) necessary for the formation of brass phase .alpha., and the central copper part of the wire is transformed into brass phase .alpha..
Claims3
A process for manufacturing of wires with a surface made of brass, for the purpose of wire electroerosion, the process comprising:
- a. providing a copper wire covered with a layer of zinc having a thickness, the wire having a periphery and a central part;
- b. heating the zinc covered copper wire to a temperature (T.sub.1) sufficient for formation of brass phase .beta.;
- c. maintaining the zinc covered copper wire at the temperature (T.sub.1) until the zinc has completely diffused;
- wherein the thickness of the layer of zinc in step a is chosen so that when the zinc is completely diffused in step c, the periphery of the wire consists of brass phase .beta. and the central part of the wire consists of copper
- d. heating the wire to a temperature (T.sub.2) sufficient for formation of brass phase .alpha.;
- e. maintaining the zinc covered copper wire at the temperature (T.sub.2) until the central copper part of the wire is transformed by diffusion into brass phase .alpha., wherein the transformation is accelerated by locally heating the wire for a short duration to a temperature (T.sub.3) which is higher than the melting temperature of the copper.
Dependencies are inferred from the claim text.