FEM MaterialMechanicalNonlinear

From FreeCAD Documentation

FEM MaterialMechanicalNonlinear

Menu location
Model → Materials → Nonlinear mechanical material
Workbenches
FEM
Default shortcut
None
Introduced in version
-
See also
FEM tutorial

Description

Creates a nonlinear mechanical material. Currently, only plasticity with simple (isotropic) hardening is available. introduced in version 0.22: Kinematic hardening is also available.

Usage

  1. To create a new MaterialMechanicalNonlinear object do the following:
  2. To edit an existing MaterialMechanicalNonlinear object:
    • Select it in the Tree view.
    • Select the material model (isotropic (simple) hardening or introduced in version 0.22: kinematic hardening).
    • Define yield points (stress [MPa] vs plastic strain). The first point must have a zero plastic strain. Press the ... button next to DataYield Points to input the points using a user-friendly list. The syntax is described in the Notes section.

Notes

  • In FreeCAD 0.19 and older versions, only 3 yield points can be specified. Since version 0.20 a list of yield points can contain as many as required.
  • The syntax should be:
stress_1, 0
stress_2, plastic_strain_2
...
With dot as the decimal separator since that's what CalculiX uses.
For example to define a bilinear model with hardening for S275 steel:
275, 0
490, 0.2
Or, to define perfect plasticity with no hardening for this material:
275, 0