PURPOSE: To prevent the generation of forming defects by forming recessed parts with a specific average diameter and average depth on the surface of a metallic die and specifying the average intervals of the recessed parts.
CONSTITUTION: At the time of forming the press material 5 for a metallic die 1, plural recessed parts are formed on a part or all of the surface that is in contact with the press material 5. The average diameter of the recessed part is formed to be 30μm-100μm, and the average depth 1μm-10μm respectively. Simultaneously, the average space of the plural recessed parts is formed to be 1.3 to 3 times as large as the average diameter. The press material 5 is a thin sheet for automobiles having the surface roughness SRa of ≥1μm. Thus, a lubricating oil is sealed in the recessed parts, and sliding property between the press material and the metallic die is improved.
| JP2013220444 | PRESS FORMING METHOD |
IMANAKA MAKOTO
KATO TOSHIYUKI
KAWASAKI STEEL CO
Next Patent: JPS6210371