##

*DEFORMATION PLASTICITY

Keyword type: model definition, material

This option defines the elasto-plastic behavior of a material by means of the generalized Ramberg-Osgood law. The one-dimensional model takes the form:

E\epsilon=\sigma + \alpha \left( \frac {\left| \sigma \right| }{\sigma_0} \right)^{n-1}\sigma |
(787) |

where **\epsilon** is the logarithmic strain and **\sigma** the Cauchy stress. In the present implementation, the Eulerian strain is used, which is very similar to the logarithmic strain (about 1.3 % difference dat 20 % engineering strain). All coefficients may be temperature dependent.

First line:

Following line:

- Young's modulus (E).
- Poisson's ratio (
**\nu**).
- Yield stress (
**\sigma_0**)
- Exponent (n).
- Yield offset (
**\alpha**).
- Temperature.

Repeat this line if needed to define complete temperature dependence.

Example:
*DEFORMATION PLASTICITY
210000.,.3,800.,12.,0.4

defines a Ramberg-Osgood law. No temperature dependence is introduced.

Example files: beampl.