FRICTION MEASUREMENT IN COLD FORMING USING TRIBO-TESTS
Keywords:
Friction Measurement, Interface Friction, Tribo – Tests, Calibration CurvesAbstract
Using tribo-tests, the interface friction which exists during forming, is measured and a suitable lubricant is applied to reduce it since it is root cause for many problems. Aluminium alloy 6063 material is tested in three tribo-tests to form various shapes whose features are used to quantify friction. Forward spike and backward cup test is carried out in addition to simple upsetting test and spike forging test to evaluate friction. Forming is simulated for various ratios of height/ diameter of the billet and for different punch diameters. Calibration curves are plotted for the three tests and the ease of conducting the test and finding the shear friction factor values are brought out. Both in simulation and experimentation, different friction situations have been tested using different lubricants. By marking the values obtained from the tribo-tests on the calibration curves, the interface friction arising during the forming process is found out.
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References
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