How does the plastic material data in the material model affect the stress results? What relation does Marc use to calculate the redistributed stress after plastic deformation?
How does the plastic material data in the material model affect the stress results? What relation does Marc use to calculate the redistributed stress after plastic deformation?
If you are using an Elasto-plastic material model, Plasticity is triggered at the yield stress defined in plasticity data. Till this point Marc will use Young's modulus and, Beyond this point, Marc will use the plasticity data defined by plastic strain vs true stress table, or any other material model coefficients such as chaboche, johnson cook etc..
Take a look at Marc-UG examples illustrating plasticity, one such example is "e024 - Sheet metal forming with solid shell element".
Thank you for your response. I will have a look at the example suggested. However, I would like to know the validity of the stress results with an elasto-plastic material model. When Marc uses the plasticity data to compute the plastic strain in the component, the stress values seen are the reduced stress values after plastic deformation or is there some correlation between the linear stress and corresponding non-linear stress? The purpose of my question is to understand the nature of stress results post the elastic limit. Is there any reference literature available?
When material goes past yield point, stress corresponding to the plastic strain will be obtained from plasticity data defined. For a detailed theory, please refer to Marc Vol.A, chapter 5 - "section Computational Procedures for Elastic-Plastic Analysis"
