Process for producing an industrial member having throughholes of high aspect ratio

Abstract

A fabrication method of an industrial part having high-aspect-ratio through-hole sections using a punch and a die, includes a first step of drilling a first hole section in a first sheet of sheet material with the above punch; a second step of lifting the above first sheet in tight contact with a stripper; a third step of lifting a tip section of the above punch so as to be slightly drawn in from a bottom section of the above lifted first sheet; a fourth step of drilling a second hole section in a second sheet of sheet material with the above punch; a fifth step of lifting the above second sheet in tight contact with the above first sheet; a sixth step of lifting the tip section of the above punch so as to be slightly drawn in from the bottom section of the above lifted second sheet, and, the subsequent steps of repeating the above fourth to sixth steps for lamination of a plurality of sheets of sheet material. Industrial parts may be fabricated, where fine through-hole sections, in which their diameter is very small, for example, 100 &mgr;m or less, and their axial length is longer by a predetermined mount or more compared with that of their diameters, are provided at high density with similar accuracy to that of hole sections drilled in one sheet of thin sheet material, even when using soft material which can be deformed.