simulating microstructres of tool steel?? 1

[aatiff]

PROBLEM
A question is put where microstructres that are found in for example tool steels can be used to analyze local stifness's and local stresses during heat treatment and mechanical loads.
The task is to evaluate and suggest a method of analyzing the effect of microstructure.`
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How can i simulate various microstructres(pearlite,martensite,ferrite etc) in abaqus.
How can i do simulation for the above given problem?

 

[corus]

I have heard about CELLULAR AUTOMATA FINITE ELEMENT (CAFE)modelling in Abaqus which may be of use for micro/macro structures. I've no experience in it but it might be worth looking at on google or whatever.

Tata

 

[MechIrl]

Depending on the complexity you are looking for you could look into crystal plasticity theory (google Huang's UMAT) or strain gradient plasticity theory. Both are used in the modelling of material micro-structures.

If you only want a very basic model you could model individual grains explicitly, assigning each different material properties depending on orientation. This will give a basic look at the effects of local stress and strain concentrations.

 

[aatiff]

how do i apporach the above given pronlem???

 

[MechIrl]

What further details do you think you need to get started? I can't be much more help without knowing exactly what you're trying to get out of the analysis.

Models based on crystal plasticity theory allow for an accurate representation of the mechanical properties of the microstructure, including crystallographic slip.

More simple models are based on continuum plasticity theory, but involve modelling individual grains with different mechanical properties to artificially introduce localized stresses due to lattice mismatch.

The choice between these modelling approaches will depend on exactly what you are trying get from the analysis. If you are not familiar with modelling micro-structures I'd start with the latter approach.

 

[loki3000]

model the crystals with voronoi/ delaunay tesselation (wikipedia it or lookup in a book) and transfer them somehow to abaqus (good luck with that).