GB1337202A - Production of copper-sheathed aluminium wire - Google Patents

Abstract

1337202 Making composite wire; bending KABEL UND METALLWERKE GUTEHOFFNUNGSHUTTE AG 25 Oct 1971 [26 Oct 1970 (2)] 49393/71 Headings B3A and B3E A method for the continuous production of copper clad aluminium wire includes bending a single strip of copper to form a sheath around the aluminium core and welding the strip edges together, all in a protective atmosphere and then reducing the diameter of the sheathed wire. The reduction in diameter is followed by heat treatment to produce a diffusion layer at the inter-face between the core and the copper sheath. An extruder 1 supplies aluminium wire 2 to storage means 3, which is fitted with guide rollers 4, 5 and located in a protective gas enclosure 7. Alternatively continuous casting apparatus may be provided. The copper strip 9 is fed from storage means 10 to a cleaning unit 13, the storage means having provision for welding strips end to end. The strip passes through a drier 14 and a brushing device 15, which has brushing rollers 16 and backing rollers 17. The copper strip is bent into a tube by a roller device 19 welded at a welding station 6 and the sheathed wire is reduced in diameter in means 20 which comprise a drawing ring or reducing rolls. The wire drawn off means may be a disc 21, or endless band or clamp and the wire is fed to a collecting drum 22. The wire is further reduced in diameter in stages and heattreated; the heat treatment may take place between successive stages of reduction. The thickness of the diffusion layer between the copper and aluminium depends on the amount of reduction which may be 80% or more, and the heat treatment temperature. Heat treatment is preferably carried out continuously as the wire emerges from the stages of the reduction means.