抄録
Ultra-smoothing bar and wire are required for the use of precision machine parts. In order to achieve ultra-surface roughness, protrusion die drawing was developed and evaluated. The protrusion die induces high contact pressure and shearing strain at surface of drawn bar. By this technology, grinding and polishing process are eliminated and fatigue life is improved. As a results, surface roughness under maximum height of irregularities 1μ m was achieved by a new design die. There were optimum protrusion height to prevent seizures between die and drawn bar.
