crack during assembly in ABAQUS 2

[mdama]

How can I check if there is a crack in any component during a snap fit assembly. Actually, there is a snap fit holding two plates. The question here is if there is a crack after assembly! How check figure this out in ABAQUS! It's a displacement control process.

 

[FEA way]

Typically it comes down to comparing the stress and strain results to various failure criteria. You can also model the crack propagation but you will have to initiate it in a selected location. Yet another way would be to include progressive damage and element deletion upom failure. This is commonly done woth metals, especially when subjected to loads like impact.

 

[mdama]

Thanks, I don't want to have a real crack in my model.
Regarding progressive damage and element deletion, how does that work in ABAQUS? Is there an option in ABAQUS?

 

[FEA way]

Damage can be defined in material properties but you need proper constants (from testing or from literature). Check the documentation section Materials --> Progressive Damage and Failure.

 

[SWComposites]

How can I check if there is a crack in any component during a snap fit assembly. The question here is if there is a crack after assembly!

Forget the FEA for now. It is only a tool that requires proper application. You first need to perform a simple hand analysis of the part. Most snap fit designs have tabs that flex during assembly. Given the geometry you should be able to calculate the required deflection, and from that the bending stress. Then using strength of materials methods and properties for the material make an estimate of the strength of the tab. Once you know how to do this should you attempt a FE analysis.

 

[mdama]

@FEA way
But with this method, I think we already know at which stress cracks initiate right? If yes, that's not what I want. I want a design direction at the onset of crack.

@SWcomposites
Do you have any references or links?

 

[SWComposites]

mdama -
What is the material?
Do you have material properties - stress-strain responses, strength values, etc?
What is the part geometry? Post a picture.