Poisson's Ratio Behavior Research Articles

Modeling the consolidation behavior of an alpha-two titanium aluminide powder

The consolidation of an alpha-two titanium aluminide powder was analyzed using an approach based on two density dependent variables: the apparent Poisson's ratio and a stress intensification (geometric hardening) factor. Uniaxial compression tests on samples with different relative densities were used to obtain the the apparent Poisson's ratio and constitutive behaviour. Microhardness tests on undeformed and deformed samples with different relative densities were used to obtain the stress intensification factor. With this information, a von Mises type yield function, modified for pressure effects, was developed and implemented into a finite element code and used successfully to model the densification of the alpha-two titanium aluminide powder.

Holographic study of non-affine deformation in copper foam with a negative Poisson's ratio −0.8

While conventional foams have positive Poisson's ratios (become smaller in cross-section when stretched and larger when compressed), foam materials have recently been defined which possess 'reentrant' cellular architectures; in these, inwardly-protruding cell ribs are responsible for negative Poisson's ratio behavior, yielding greater resilience than conventional foams. Double-exposure holographic interferometry is presently used to examine the microdeformation of a reentrant copper foam. Attention is given to the nonaffine (inhomogeneous) deformation of this foam.

Poisson's ratio behaviour in various crystalline rocks: application to the study of the Earth's interior

The study of Poisson's ratio (σ) behaviour in various crystalline rocks under different temperatures and pressures shows this parameter to depend upon the rock composition rather than upon P- T conditions. The results of this study are presented in the form of a comparison of σ(z) distributions within the consolidated crust and continental upper mantle and the specific variations of σ in crust and mantle rocks underlying the Voronezh crystalline massif (VCM). These investigations, which are based upon seismic and seismological data as well as high pressure experiments, should clarify in particular the composition and petrology of the Earth's interior.