A Three-Dimensional Multi-scale Plasticity Model for Metal-Intermetallic Laminate Composites Containing Phases of the L12 Structure

Abstract

A three-dimensional plasticity model was developed and applied to metal-intermetallic laminate composites containing phases of the L12 structure. A multi-scale approach that combined the methods of continuum mechanics and dislocation kinetics was used. This model takes account of the different mechanisms of self-locking superdislocations, the dislocations and the dislocation walls’ density storage for each type of layer at the micro-scale. At the meso-scale, the solutions to the dislocation kinetics equations, in the form of stress–strain curves, were used to create the properties of a three-dimensional representative element. The numerical simulation study of the macroscopic deformation was carried out with the finite element method using the dynamic model of continuum mechanics, which included the classical conservation laws, constitutive equations and the equation of state. It was shown that the simulation results generated using this model were in good agreement with the mechanical tests conducted on the single crystals of the L12 structure. The model provides an excellent description of the high-temperature plastic strain superlocalization effect of single crystal intermetallics of the L12 structure. This paper describes the numerical results of the study of the tension and compression tests of metal-intermetallic laminate composites containing phases of the L12 structure. The model allows the description of the distribution of the accumulated plastic strain inhomogeneities and is capable of predicting the strengthening properties and plastic behaviour of the metal-intermetallic laminate composites containing phases of the L12 structure.