SIMULATION OF STRIP ROLLING BY ELASTOPLASTIC CONTACT BEM WITH FRICTION

摘要

A boundary element method ( BEM ) is presented for two-dimensional elastioplastic finite strain and finite deformation analysis of contact problems, with friction. The contact bodies are treated in separate regions. The contact conditions are used to join the different system of equations for different regions of contact bodies. All equations for the contact problems are obtained, which including multi-nonlinearities (material nonlinearity, geometric nonlinearity and contact nonlinearity). Incremental and iterative procedures are used to find contact pressure and frictional stress. Initial strain rate algorithm and work hardening material behavior can be assumed in the plastic analysis. It is employed to analyze normal contact problems and rolling contact problems. Strip rolling process is of particular important in practical applications. With rollers as elastic bodies, workpieces as elastoplastic bodies, rolling problem can be viewed as a frictional elastic-plastic contact problem. With a few assumptions in the simulation of strip rolling process, a novel method is proposed for analysis of strip rolling problems. Several examples are presented, and the results on contact pressure and frictional stress show excellent agreement with that of analysis and finite element methods.