| 摘要 |
<p>A metal tube is cold formed into a stamped member by filling the tube with a liquid change-of-state material, freezing the change-of-state material, sealing the tube containing the solid change-of-state material, and stamping the tube in a die. The change-of-state material compresses during the stamping step to force the walls of the tube to conform to the die cavity, eliminating the need to pressurize the tube prior or subsequent to stamping. Additionally, the solid within the tube provides support to the wall of the tube during a piercing step to form a hole in the tube having less deformation surrounding the hole than a comparative tube pierced without having the solid fill. After the stamping or piercing steps, the change-of-state material is melted and drained from the tube. Further, a tube is pierced by forming an outwardly bulged area and piercing the tube in the outwardly bulged area while simultaneously depressing the tube to substantially flatten the outwardly bulged area.</p> |
