Why is FEA of plastic parts so often wrong?

摘要

We've all seen the presentations, a series of impressive-looking color plots showing a finite element mesh, with professional-looking color gradients representing peak stresses.Heads nod knowingly, and the "experts" conclude that the part is well designed and ready for tooling release. Drawings are released, and injection molds are built with all stakeholders confident that the part is well within design loads. Fast-forward four months: Tool verification is complete, first articles are in and looking good, and it's time for the first load test of a molded part.