短冊状素材を用いた板側面からの成形による高材料歩留り精密部品製造技術の開発

抄録

Fine blanking (FB) is well known as a method for obtaining a clean-cut edge in the manufacture of a plate-like part having a sliding portion and/or a fitting portion on the side face of the part. However, FB in general is disadvantageous for good usage of precious steel material because of the unavoidable large web width. Accordingly, to manufacture precision plate-like parts with high material usage, first, a strip material having a thickness corresponding to the thickness of the finished product was cut from the coil material. Then, forming was carried out from the side of the plate surface with a punch and a knock -out punch in which the shape close to the final product was divided into approximately half. Thereafter, the forged product, which includes the defects from cutting, was blanked into the final product shape while being restrained by part of the side wall of the die. The method resulted not only in precious stainless-steel components,such as small arms used in large number in an automobile turbocharger, each having a clean-cut edge without fracture along the sheet thickness, but also in drastically improved material usage.