LARGE ELASTO-PLASTIC DEFORMATIONS OF WORK-HARDENING METAL ALLOYS.

The work outlined in this research demonstrates the applicability and effectiveness of the elasto-plastic model presented elsewhere by the first author in solving complex (i. e. , any shape and any deformation) finite deformation problems. The use of the Lagrangian formulation in this work elimiates the controversy regarding the choice of the appropriate co-rotational stress rate, and provides a more convenient theory than the more common spatial formulation. The aluminum alloy 2024 is used in this work as it closely displays the properties outlined by the proposed constitutive equations. The problem of analysis of displacements, stresses, and strains in elements made of this material subject to arbitrarily large deformations under the conditions of plane strain or plane stress is formulated in terms of the finite element method. Numerical examples include the bending of a moderately thick plate and the stress concentration problem of a plate with a hole subjected to a uniform uniaxial loading. Experimental verification is provided for the bending of the moderately thick plate.