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The paper provides an overview of recent advances and applications of One Step FEM solvers in the automotive industry. The advances include, among other things, 1. Enhanced pre-processing (e.g. i. Integration with CAD Systems, ii. Automeshing), 2. Die processing geared functions (e.g. i. Automatic tipping, ii. Autoboundary conditions; to reduce effort in selecting the boundary conditions for achievement of a specific target strain in the panel), 3. More robust mechanics and realistic modeling of process (e.g. i. Autobending to accommodate membrane as well as bending and unbending effects, ii. Passive force formulation for a more realistic modeling of the external forces required to form the part, as well as iii. Curved binder capability; for more accurate prediction of binder effects), and 4. Enhanced post-processing and interpretation of results (e.g. i. Residual stresses, ii. Advanced FLD manipulation, iii.

Surface defects occur during forming, material unloading and during further material processing. During forming operations the compressive forming stresses are the cause of defects. During material unloading and further material processing, springback and residual stresses are the major cause of such defects. The conditions for the occurrence of surface defects at these three stages are examined and discussed. A computer aided methodology is presented for estimation of the residual stresses, application of the approach is given for some practical examples.

The paper describes a methodology, developed for process engineering at the quoting stage, for matching the press requirements with the tooling requirements in the quest for achieving a quality pressing, with low tooling and press maintenance costs. The starting point is the process plan of the part. The approach is based on subdividing the deformation of the part within a station into elemental deformation regions. The load-displacement diagram for each elemental region is calculated individually, and then totalled to estimate the total load-displacement curve for each forming station. The total energy requirements, as well as the change of the load centre during the stroke for each forming station, is then calculated. The procedure also incorporates the effect of change of timing (e.g. staggering of actions). The approach is then extended for the case of multiple dies acting on the same press (e.g. transfer press and progressive tooling).