A new friction testing method based on combined forward conical can-backward straight canextrusion is proposed in order to evaluate friction characteristics in severe metal forming operations.By this method the friction coefficient along the conical punch surface is determined knowing thefriction coefficient along the die wall. The latter is determined by a combined forward and backwardcan extrusion of straight cans. Calibration curves determining the relationship between punch travel,can heights, and friction coefficient for the two tests are calculated based on a rigid-plastic FEManalysis. Experimental friction tests are carried out in a mechanical press with aluminium alloy A6061as the workpiece material and different kinds of lubricants. They confirm that the theoretical analysisresults in reasonable values for the friction coefficient.
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