This thesis presents a version of the explicit time integration finite-element method, DEFEL, for metalrolling problems. This method is capable of analyzing both the dynamic and static problems, and is effective in calculating the stress, deformation, and thermal behavior of metalrolling problems. DEFEL formulation utilizes the mass and capacitance lumping technique with explicit time integration to develop a code which does not require the formulation of global mass, stiffness and capacitance matrices. The equations of motion are decoupled and solved node by node. The computer storage requirements are small and the program can run on a microcomputer. The modification of DEFEL to simulate metalrolling problems and the implementation of heat transfer in the code are the main contributions of this thesis. Four sample problems in the area of plane strain rolling are analyzed by the modified code: crop loss in billet rolling, curling of strip in non-symmetrical rolling, roll force and torque calculations in steady state sheet rolling, and temperature distributions in non-isothermal cold and hot rolling. DEFEL results have been compared with existing experimental, analytical, and/or numerical results. It is concluded that this version of DEFEL calculates thermomechanical response of both the transient and steady state processes with reasonable accuracy. In addition, it is computer-resource efficient.
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