Static Implicit vs. Dynamic Explicit Finite Element Analysis for Ring Rolling Process Modeling

Abstract

Over the past two decades, various finite element formulations and solution techniques for metal forming analysis have been developed. Most finite element codes for bulk metal forming used in the industry today are based on static implicit solution schemes wherein a non‐linear system of equations is solved iteratively for each time increment. For simple 2D problems, static implicit analysis models are generally known to be more accurate and efficient than dynamic explicit analysis models. However, for complex 3D forming problems, the static implicit procedures encounter a number of inherent difficulties especially in incremental forming processes such as ring rolling in which several surface nodes repeatedly make contact with and separate from the dies. Static implicit finite element formulations require a very long computational time for the analysis of ring rolling. Several solution techniques have been developed to reduce the computational time of static implicit finite element analysis, namely the dual mesh technique, Arbitrary Lagrangian Eulerian (ALE) technique, etc. The dynamic explicit method on the other hand appears to be very effective in analyzing complex incremental forming problems. In this paper, a comparison of the analysis results obtained using dynamic explicit finite element method and static implicit method using a dual mesh approach is presented.