Copper wire with thick tin coating, esp. jumper wire - where intermediate wire drawing is used between two electroplated tin coatings, and wire is then finally drawn and annealed

摘要

Copper wire is continuously electroplated with min. 7 microns tin (I), and then drawn (II) through a die to compact the tin(I). A second electroplated tin coating (III), min. 7 microns thick, is applied, followed by drawing (IV) to final size. The wire is next fed vertically through a furnace for brief annealing at above 400 deg.C and rapid cooling, to obtain over 3 microns Sn, esp. 7 microns Sn on the finished wire, which is pref. 0.2-1.2 mm dia. Drawing (IV) pref. uses a wire speed of 12-24, esp. 15-20 m/s; and the pref. plant includes two electroplating units sepd. by a drawing machine, and followed by a second drawing machine and a furnace. Esp. used in the inexpensive high-speed mfr. of jumper or hook-up wire.