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Describes the development of a static‐explicit type finite‐element formulation based on non‐linear elastic plastic shells, non‐linear contact friction and Barlat anisotropic plasticity with modified corner theory. Newly introduces the spin of the anisotropic axes as a means of deriving the objective stress rate. Demonstrates that a C⁰ continuous shell is an efficient finite element for large‐scale computation. Uses membrane shell theory to derive a kinematic description of the external contact force. Offers an explanation of the ways in which the material, press load and lubrication affect the deformation and strain localization in the automotive sheet metal forming process. Demonstrates a trial of virtual manufacturing incorporating finite‐element simulation, a visualized inspection system and a heuristic process optimization scheme.

Describes the development of a dynamic‐explicit finite‐element simulation code based on anisotropic elastic‐plastic theory and non‐linear contact friction theory. Points out that whereas in industrial production the dynamic‐explicit finite‐element code has proved to be an efficient and robust tool for sheet metal forming, in the automobile industry sheet metal forming is usually a quasi‐static process; therefore seeks to make clear the dynamics of deformation and strain and to evaluate mass scaling, damping scaling and material viscosity scaling parameters. Introduces the penalty method and the kinematic description method as means to derive a rate‐type contact force formulation employing the four‐node degenerated shell finite element. Also introduces the jewely patch scheme to describe the tool geometry. Analyses the hemispherical punch deep‐drawing of a square plate and compares this with the experimental results. Confirms the applicability of the newly developed finite‐element code to the quasi‐static forming process.

Describes the development of a dynamic‐explicit type finite‐element formulation based on elastic/crystalline‐viscoplastic theory to predict the dynamic forming limits of sheet metal. Formulates an evolution equation governing all the slip stages of a single crystal, by modifying Pierce and Bassani’s crystalline plasticity models. Interprets precisely the experimentally observed hardening evolution. Takes account of the importance of the strain rate and temperature sensitivity of the material in predicting dynamic plastic instability. Analyses the deformation and strain localization in a rectangular sheet under stretching, in relation to the plane strain assumption, using the numerical results to demonstrate the influences of tension force and temperature on strain localization, and to show the temperature dependence of shear band formation. Demonstrates that the deviation of tension direction from the axis of symmetry of a single crystal causes non‐simultaneous sliding between primary and conjugate slip systems, resulting in S‐shaped non‐symmetrical deformation.