| 摘要 |
<p>A sheet metal member, comprising an upper die (6) having an ironing punch (5) and a lower die having an ironing punch (7), wherein an inward flange part (3) is raised axially so as to form it integrally with the inner periphery of a cylindrical boss part (1) by these molds. The ironing processing for forming the inward flange part (3) should desirably be finished to a final shape, using a plurality of metal dies and by repeating an ironing several times.</p> |
