A method for making hollow workpieces

摘要

A method for making hollow workpieces such as beverage containers with a circular die in which an aluminum alloy is strip cast whereby the alloy is solidified rapidly without substantial precipitation. Thereafter, the aluminum alloy is formed into a cup which is drawn and passed through one or more dies to iron the walls of the cup and thereby lengthen the side walls thereof using at least one circular die having a die angle of less than about 6 degrees and a chamfer angle of less than 35 degrees. It has been found that the use of such die angles prevents or minimizes galling and tearoffs.