Adjustable drawbead and variable contact pressure as tribological influences in sheet metal stripe sliding test

Abstract

The paper presents the experimental analysis of the influence of variable drawbead height and variable contact pressure on drawing force in thin sheet metal stripe drawing test. For the needs of experiment, a computerized device was made which enables the accomplishment of previously specified functional dependencies of drawbead height and contact pressure on duration of stripe drawing process. It is possible to monitor the simultaneous influence of friction conditions (dry or application of lubricant), drawbead roundness radius (2mm and 5 mm), 10 functional dependencies of drawbead height and 10 functional dependencies of contact pressure on drawing force of sheet metal stripes made of various materials. Stripe dimensions are 250 x 30 mm, and drawbead thickness is 10 mm. Maximal pressure value is 20 MPa, and maximal drawbead height value is 8 mm. Within the results presented here, the influence of two types of variable pressure function in combination with one constant value and two variable drawbead height functions are monitored. Dependencies of drawing force indicate the possibility for applying the specified influences in order to correct the forming process course in computer simulations and systems for deep drawing processes control.