抄録
Shearing is a commonly used method of cutting materials for former from bars or wires. However, the cut face shape of a material after shearing is poor because droop is formed at the edges of the cut face. It is necessary to alter the cut face shape after shearing for use in former. In this research, we developed a new shearing method in which shearing is combined with twisting to achieve a short cutting time with a length high accuracy and a cut surface without droop. Annealed low-carbon steel bars (diameter: 1.96 mm) were used for the experiment. The specimens were twisted after a static shear force was applied to the bar. As a result, the droop height decreased markedly. In addition, to restrict the work hardening area by applying torsion, the bar was twisted after shear stress, which was slightly less than the yield stress, was generated at the clearance with the loading of a large static shear force. The equivalent stress at clearance exceeded the yield stress, when the torsion was small because the shear stress was large. Therefore, the twisted area became narrow, and work hardening was restricted.
