Finite element modeling of anisotropic properties of Cu-Ag metal matrix composites

This research investigated the sensitivity of the mean phase strains in a heavily drawn copper-silver fiber composite to the inherent mechanical anisotropies resulting from the texture produced by the drawing process. The work performed here is a precursor to the neutron diffraction experiments to be performed to advance the understanding of the residual stress development during the fabrication process and how these residual strains change as a function of loading. Copper-Silver (Cu-Ag) metal matrix composites are used as high strength conductors for high performance pulse magnets. To produce the filamentary nature and extreme work hardening a cold-working co-deformation fabrication process is used which in turn induces crystallographic alignment of Ag fibers and Cu matrix. In the limiting case the material behavior is close to single-crystalline Ag fibers embedded in a single-crystalline Cu matrix. Since this means that the mechanical elastic properties will be strongly anisotropic we investigated the sensitivity of the mean phase strains to the degree of anisotropy using a three dimensional finite element model. The anisotropic elastic properties of the Ag and Cu were incorporated. Several different loading conditions were applied. Results of the various loading conditions were then used to obtain an estimate of the mean phase strains of the composite.