Different material for different elements. How to implement in Abaqus? 1

[Yunus9696]

Hello everyone

How could I assign a different material to each element in an Abaqus model?

for example:
I have two materials and a model consisting of 10 elements, I want to start the solution with Material 1 and if each element's von mises stress exceeds 5 KPa, Abaqus changes that element's material to Material 2.

How can I reach this goal?

If Scripting works please give me some hints on the needed commands.
If a UMAT subroutine is needed, please give me the same hints.

Application: Bone Healing Abaqus model

Best regards,
Yunus.

 

[FEA way]

You can do it as long as it will be the same material model so that you only change its properties. Field variables can be used for this purpose. Check this thread for some hints:

https://www.eng-tips.com/viewthread.cfm?qid=466763

However, in your case also USDFLD subroutine will be needed since you want to change the material properties using a criterion based on a solution output. See the documentation chapter about this subroutine for its syntax. There are also some examples of its usage in the documentation.

 

[Yunus9696]

Thanks FEA way for your great hint.
I'm trying to learn and implement Abaqus subroutine USFLD and am struggling with the following Abaqus terms' meanings and applications:
1. field variables
2. material point (and material point quantities)

would anybody please help me with the definitions and examples of the above-mentioned terms since I haven't found any useful website links online.

Best regards,
Yunus.

 

[FEA way]

Field variables are additional variables that control certain data (like material properties) during the analysis. They can be used also without the subroutines in some cases (this is described in the forum thread I linked before). Material points are basically integration points of finite elements.