Abstract
These experiments were carried out for the production of aluminum ultra-fine wire for transistor lead by clothing it with copper and for studing its mechanical properties.
The results obtained were as follows:
(1) Pure aluminum ultra-fine wire produced by the method of clothing with copper was fully available for transistor lead wire, because its tensile strength was 12-13kg/mm2, its VHN was about 33, and its hardness was uniformly distributed over the whole.
(2) The desirable time for process annealing of the copper clad aluminum wire should be less than 1hr at 250°C or less than 1/2hr. at 300°C when the rate of cold drawing was above 80%.
(3) Intermetallic compound was formed on the boundary layer by heating for more than 2hr. at 250°C or more than 1hr. at 300°C and its hardness was higher than 500 VHN.
