Description
A hardened layer around 40 ?m referred to as the “additional shear strain layer” is generated beneath the surface layer of the wire. Through tensile tests of fine wire with and without the additional shear strain layer, it becomes clear that this layer affects the strength and ductility of fine wire. The surface layer with the additional shear strain was thinned after one-pass drawing. As a result, it was ascertained that the tensile strength decreased as the surface layer was thinned in all wires.
