Mass scaling and stable time step estimates for isogeometric analysis

Summary Metal stamping is one of the most cost effective manufacturing methods for producing precision parts. The precision of the parts is a function of the uniformity of the material used for the blank and the design of the dies. During the metal stamping process, the blank undergoes large, inelastic deformations, and once it is removed from the dies, springs back to a shape different from the die. This spring back must be accounted for in the design of the die, and its prediction is a major challenge in computational mechanics. Isogeometric analysis, which uses the same basis functions as the computer-aided design programs used to design the shape of the part, is an attractive alternative to traditional finite element analysis for metal stamping. Mass scaling, and the underlying stable time step estimates, that are commonly used in metal stamping simulations are presented for isogeometric analysis. Example calculations are presented to demonstrate the effectiveness of isogeometric analysis in metal stamping. Copyright © 2014 John Wiley & Sons, Ltd.

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