| 摘要 |
<p>PURPOSE: To provide such extruded material for expansion working as can be satisfactorily worked into a plate by expansion. CONSTITUTION: An extruded material for expansion working is a thin material which is provided with more than 1 or 2 corner parts 2, 4 circular-arcuate in cross section and which is worked in plate-like expansion by opening the corner parts 2, 4; each corner part 2, 4 is formed such that L1 -L2 , which is a difference between the outer circumferential length L1 of the corner part 2, 4 and the circumferential length L2 in the center of the thickness direction is 2.0 to 10.0% against the latter circumferential length L.</p> |
