A Method for Determination of Friction Coefficient in Sheet Metal Forming of Magnesium Alloy

Abstract

A new method for determination of friction coefficient in sheet metal forming of Mg alloy AZ31B is presented in this paper. The method is based on the bulging test of sheet metal in which the specimen is processed with a hole at the center. The diameter of the hole will increase along the stroke of the punch and the dimensional change of the hole has a certain relationship with the friction coefficient at the punch/specimen interface. Thus, the friction coefficient can be determined indirectly according to the dimension of the hole in the bulging process. The bulging process of the sheet is simulated using FE code DEFORM-2D. The analysis model is set up according to the experiment of the bulging and the friction calibration curves are generated from the simulations of the bulging by setting different coefficients of friction. The friction coefficient can be determined by measuring the hole dimension during the bulging process and comparing it with the friction calibration curves.

Finite Element Modeling of Frictional and Material Anisotropy During Forming of Steel Cylindrical Cups

“…On the other hand, the accuracy of FEM simulation depends on several parameters including e.g. type of constitutive equations used and friction phenomenon [1]. Previous investigations of authors [2,3] show that numerical analysis of the deformation mechanism of sheet metal forming is very complicated due to the strong non-linear nature of the FE model procedures.…”