Necking Formability of Aluminum D&I Cans during Smooth Die Necking or Spinflow Necking

摘要

The material's behavior of aluminum D&I cansmade from different types of body sheet has been investigatedduring the reduction of the neck diameter. In smooth die neckingwith multiple stages, the smaller neck diameters lead to thickerand softer thickwalls, and earing appears at the trimmed canedge. The earing occurs at 45, 135, 225 and 315 degrees to therolling direction. The thickwalls at the 90 and 270 degreepositions thicken and soften the most. In spinflow necking thethickwall thins and hardens, and earing appears. The earingoccurs at various positions around the trimmed can edge in thematerial from the hot rolling-(intermediate annealing)-coldrolling processes. In spinflow flange reforming, the thickwalland earing variation around the circumference are reduced bythe effect of a stop ring incorporated into the reformer.