Utilization of Forming Tool with Variable Blankholder Force for Drawing of Al Alloys

AbstractDrawing of stampings technology is nowadays the most using technology for sheets processing. Because of stamping's weight reduction is these days actual sheet processing from aluminium alloys which by their properties differ a lot from commonly using deep-drawing sheets. To achieve maximal plastic deformation with material fracture is necessary to use sheet with required mechanical properties and properly chosen forming technological properties. Common tools for deep-drawing don’t enable to lively reply of necessity to change blankholder force during sheet drawing. On the experimental tool for deep-drawing with variable blankholder force are in the paper evaluated two variants of drawing methods for irregular shape of stamping. In the first case was stamping from AA6016 alloy designed with constant blankholder force. In the second case was blankholder force optimized and during drawing was changed in dependence on drawing depth. Calculation of blankholder force in dependence on drawing depth was carried out by means of numerical simulation in software PAM-STAMP 2G. Result of optimalization was strain distribution change in critical places of stamping. Strain distribution on stamping is measured by means of optical system ARGUS