When a piece of rubber in its original shape that is cuboid is pulled along its sides what happens? The rubber will get compressed from the middle. The original length and breadth of the rubber, which is L and B respectively when pulled longitudinally it, gets compressed laterally. The length of the rubber increase by the amount of dL and the breadth increases by dB.
When it comes to anisotropic solids such as honeycombs, single crystal, and some fibrous composites, the physical properties of this material including the Poisson’s ratio and Elastic Moduli depends on the direction in which they are stretched or bent. The Poisson’s ratio can be positive or negative for the large magnitude of this kind of anisotropic materials.
The context of the transient test such as creep and stress relaxation etc have an effect on the Poisson's Ratio of the viscoelastic material. The Poisson's Ratio also depends on the frequency and the phase angle if the deformation executed is sinusoidal in nature. In most of the cases, the transverse strain is out of the phase and have the longitudinal strain when it comes to viscoelastic solid.
The phase transformation can have a considerable impact on the Poisson's Ratio of a material. The bulk modulus most softens near a phase transformation but the shear modulus does not have much impact. The Poisson's Ratio decreases along with the vicinity of the phase transformation and can even go to negative values. Therefore, it is very important to study the effect of phase transformation on the Poisson's ratio of a material.
The speed of propagation and reflection of the stress waves are affected by the Poisson's ratio of the various materials. The ratio of the compression to shear wave is very important from the geographical application point of view as it helps to infer the nature of a rock situated deep in the earth. The wave speed ratio depends upon the Poisson's ratio as well. The Poisson's Ratio affects the distribution of stress around the cracks as well as the decay of the stress.