| 摘要 |
PROBLEM TO BE SOLVED: To provide a blanked product excellent in fatigue characteristics, corrosion resistance at the edge surface, and external appearance by coating the edge surface with a plated layer which flows in a plastic manner upon blanking or extruding. SOLUTION: A worked product is either blanked out of a plated steel plate or partially protruded from a plated steel plate. The blanked edge surface or the protruded edge surface is composed of a sheared surface and is coated with a plated layer L being expanded during the working. A Zn plated layer, an Al plated layer, a Zn-Al alloy plated layer, and a Zn-Al-Mg alloy plated layer are preferable as the plated layer L. A blank M is provided between a die having a cavity corresponding to the product shape and a punch of the size a little larger than that of the cavity. The punch is forced into the blank M to shear 60 to 95% of the plate thickness, thereby forming a product part P2 being protruded from the blank M. To obtain a blanked product, the product part P2 is separated from the blank M by shearing the remaining plate thickness from the other side of the product part P2 with flat pressing.
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