GB415037A - Improvements in or relating to the electrodeposition of metal - Google Patents

Abstract

415,037. Electrodeposition of metal. TENNANT, W. J., 111, Hatton Garden, London.-(Copperweld Steel Co. ; Glassport, Pennsylvania, U.S.A.) Feb. 14, 1933, No. 4563. [Class 41.] An article produced by electrodeposition of metal on a core, such as a copper-coated steel wire, is heated adequately to develop union between the base and the coating and is thereafter drawn through a die to decrease its diameter, increase its length and heal porosity developed during the heating step. Care must be taken that the resulting product is not oxidized, e.g. the heating may be effected in hydrogen or an inert atmosphere. The temperature of the heating operation should be above 600‹ F., but below that at which the coating or the core begins to flow, e.g. 1900‹ F. in the case of copper. Hot or cold drawing may be employed; hot drawing should be effected under non-oxidizing conditions. Cores having coatings of considerable thickness may be treated. In an example a steel core 0À375 inches in diameter is built up with copper to a diameter 0À467 inches and after heating is drawn to its original diameter. The coating so treated has the grain structure of annealed wrought metal. Coatings may be deposited in several stages. A main deposit of copper from an acid bath may be preceded by a layer of nickel, tin, zinc, iron or copper from a cyanide bath. In the apparatus shown, the wire W is passed through a tube 10, provided with a water seal 9 and supplied with hydrogen through a reducing valve 13. The tube is enclosed within a furnace 11 heated by burners 12. The tube 10 is tapered at the delivery end and is enclosed by a die-holder 17 packed with the drawing lubricant consisting of graphite with very little grease. After treatment the wire may be subjected to further heating and working operations, e.g. a hot drawing operation may be followed by cold drawing and then by heat treatment. Porous zones are not developed in such further treatment. Specification 200,854, [Class 83 (ii)], is referred to.