Wrinkling behavior of rectangular plates under lateral constraint

Wrinkling (buckling) during a sheet forming process is a major consideration when designing part shape, die geometry and processing parameters. In most instances, the sheet metal is constrained to some extent between binders and/or matching dies at some stage during processing. In this paper, we will examine the wrinkling behavior of both elastic and elastic-plastic sheet subjected to edge compression and lateral constraint. A criterion for wrinkling under such constraint is established using a combination of finite element analysis and energy conservation. Various methods of incorporating imperfections into a finite element model in order to capture buckling and post-buckling behavior are discussed. A simple and practical form of imperfection for predictive modeling of buckling is given along with a discussion of the sensitivity of the solution to the magnitude and distribution of imperfections. Using the proposed form of imperfection, we are able to accurately simulate the wrinkling behavior under complicated boundary conditions in a predictive manner.