Home / Examples / Stress Analysis [Galileo] / Example 40: Deformation of Elasto-Plastic Multilinear Material

Example 40: Deformation of Elasto-Plastic Multilinear Material

General

• A plate with elasto-plastic multilinear material is deformed by forced displacement.
   

• The deformation, the displacement distribution, and the stress distribution are solved.
   

• Unless specified in the list below, the default conditions will be applied.

 

• Obtain this session's project file. (Right-click and choose 'Save link as')
  
  

• Results will vary depending on Femtet version and the PC environment.

 

• Elasto-plastic analysis is available in an optional package.

 

Analysis Space

Item	Settings
Analysis Space	Axisymmetric
Model Unit	m

 

 

Analysis Conditions

Item	Settings
Solver	Stress Analysis [Galileo]
Analysis Type	Static Analysis

 

The nonlinear analysis is set up on the Step/Thermal Load tab as follows. All results are output.

Tab	Setting Item	Settings
Step/Thermal Load	Step/Reached Temperature Setting	Substeps of Step 1 : 10
	Options for the Nonlinear Analysis	Save the results of substeps : Select

The default number of substeps is 20. It is adjusted to 10 in this example. Therefore the forced displacement is incrementally increased by 10%.

[Save results of substeps] is selected by default to see the results at all 10 steps.

Model

This model is axisymmetric. The axis of symmetry is Z-axis. The 3D body is actually a circular rod.

The body is made of the elasto-plastic multilinear material named "ML" and a forced displacement is applied on the top face of the body.  

Body Attributes and Materials

Body Number/Type	Body Attribute Name	Material Name
2/Sheet Body	BA1	ML

 

The material properties are set up as follows:

Material Name	Tab	Properties
ML	Elasticity	Material Type: Elasto-plastic/Multilinear Young's Modulus: 69x109 [Pa] Poisson's Ratio: 0.3   The plastic strain-stress multilinear curve of ML is shown bellow. This characteristic has been set on the [Plastic strain - Stress] Multilinear table in the dialog box which appears when the button located in the [Plastic Strain - Stress Multilinear Curve] is clicked.

Boundary Condition

Boundary Condition Name/Topology	Tab	Boundary Condition Type	Settings
Sym_z/Edge	Symmetry/Continuity	Symmetry	Select Reflective
Pull_z/Edge	Mechanical	Displacement	Select the Z component. Uz=0.2x10-3 [m]

Results

The displacement at the step 1 is shown below.

The color contour shows the distribution of accumulated equivalent plastic strains.

True Scale is selected on the Displacement Diagram tab of Graphics Setup.

[Full Model] is selected.

 

 

High strains are exhibited in the narrow part of the body.

 

The charts below shows Accumulated equivalent plastic strain vs. Modes and von Mises equivalent stress vs. Modes at (0, 0, 0).

 

- Accumulated Equivalent Plastic Strain

- Von Mises Equivalent Stress

 

A1100 (ML)'s plastic strain and Mises's equivalent stress are plotted together for comparison.

These plots match quite well.