Instability and damage effects in the modeling of metal forming Original Research Article

Instability and damage effects in the modeling of metal forming Original Research Article Pages 421-437 G.J. Creus Close preview | Related articles | Related reference work articles Abstract | Figures/Tables | References Abstract In this paper we describe some recent work of our group at CEMACOM on elasto-plastic deformations with applications to metal forming and impact using numerical and experimental procedures. The basic code is METAFOR, developed by LTAS, Belgique. Initially we discuss in very general terms the procedure for the integration of stresses that may give rise to numerical instabilities and propose a solution. Then, we describe the remeshing procedure used, needed to correct the mesh distortion that appears with large plastic deformation. In the third place, we present some initial results on work with coupled effects of temperature, plasticity and damage. Finally, we describe an experimental procedure to determine in one test, both the friction coefficient and the stress–strain relation. For all this items we present numerical and/or experimental results. Article Outline 1. Introduction 2. The code metafor 3. Instability effects in the integration of stresses 3.1. Generalized strains, stresses and hyperelastic relations 3.2. Incremental integration procedure 3.3. The case of simple shear 3.4. Final remarks 4. Remeshing 4.1. Example: heading process 4.2. The remeshing procedure 4.3. Transference of state variables 4.4. Example 2: penetration of an aluminum cylinder by a rigid conical-nose rod 5. Plasticity, temperature and damage 6. Experimental determination of friction coefficient and stress–strain curves 6.1. Approximate analytical and numerical solutions 6.2. Experimental procedure Acknowledgements References