Poisson's ratio
When a material is compressed in one direction, it tends to expand in the other two directions perpendicular to the direction of compression. This phenomenon is called the Poisson effect. Poisson's ratio v is a measure of the Poisson effect.
Poisson's ratio bounded by two theoretical limits: -1 < v ≤ 0.5. In fact that E, G, and K are all positive and mutually dependent. However, it is rare to encounter engineering materials with negative Poisson ratios. Most materials will fall in this range: 0 < v ≤ 0.5. For perfect incompressible material we have theoretically v = 0.5. However, we suggest v=0.495 in order to avoid too small time steps.
Material | Poisson's ratio |
---|---|
Gold-pure | 0.42 |
Aluminum | 0.33 |
steel | 0.27 – 0.3 |
Titan | 0.3 |
Foam | 0.1 – 0.4 |
Concrete | 0.2 |
Glass | 0.24 – 0.29 |
Rubber | 0.48 – ~0.5 |
Cork | ~0 |
Polystyrene | 0.34 |