Failure criteria for composite material 1

[alimansur]

Hi everyone
I am new here and I need your help. I am trying to model a composite plate impacted by a piercing bullet at different velocities. I don't know what failure criteria should I use to get a very good result and to see how the plate fails.
I use Abaqus 6.7.
Please can any one help me in that and thank you in advanced.

Ali

 

[rstupplebeen]

Start by researching what the different failure models were developed to model.

More information regarding your material data and or test data is needed. Also what is your composite plate's composition is it a composite/ceramic, aramid/phenolic...? Hopefully someone has a similar system.

If neither of these options pan out it will be trial and error to determine what model's you specific system.

I hope this helps.

Rob Stupplebeen

 

[alimansur]

Thanks Rob I really appreciate your response.

I am working in ceramic-metal composite. and I want to consider ductile and shear damage but the problem is how to get the parameter needed in Abaqus like fracture strain ,stress triaxiality and strain rate for ductile and shear damage.
is there any way to calculate them or are they given somewhere. I have the other properties density, E, v.

Thanks again

Ali

 

[Rikuson]

Hi alimansur

I'm doing my project and same problems happened to me.

As I know, you could find these material properties from published paper or look them up from JMatPro software.

Hope this helps.

 

[gwolf2]

> I use Abaqus 6.7.

Why are you not using the latest version?

 

[alimansur]

Hi Rikuson

Thank you for your response.
I think JMatPro software gives the material properties.I already have the material properties but the Problem is the values for fracture strain ,stress triaxiality and strain rate for ductile and shear damage. I don't know how to find them. I have read the documentation manual but it didn't help so how can I define these value.

hi gwolf2, I use 6.7 because it the version my professor has asked me to use. Is there any difference between Abaqus 6.7 and the latest version

waiting for your response guys

 

[SWComposites]

It is highly unlikely that you will find existing data for fracture strain ,stress triaxiality and strain rate for ductile and shear damage. You are going to have to run some tests to determine appropriate values for your ceramic-metal composite material.

 

[alimansur]

what kind of tests I should run. is it a tensile/compression test or anything else.

 

[rstupplebeen]

Look for ASTM standard tests for similar material systems. Rubber has significantly different tests than carbon fiber epoxy. Different failure modes are likely in different materials. I hope this helps.

Rob Stupplebeen

 

[amubashar]

I believe that you are referring to the ductile metal damage and failure criterion implemented in Abaqus. A good source of information about calibration of this material model is the paper by Hooputra et al, referred in section 20.2.2 in Abaqus 6.9 user's analysis manual (I think the model is based on work presented in this paper). The paper explains a combination of uniaxial and biaxial tests to obtain material parameters which is not easy or always possible.

There are other damage and failure models available in Abaqus that might be easier to calibrate. Depending on your material behaviour, you can use VCCT, XFEM, cohesive zone model, Gurson model etc. From your problem description, I suppose that you are using Abaqus/Explicit. There are two additional failure models in Abaqus/Explicit for high strain rate dynamic problems (Sec 19.2.8 Abaqus 6.9 user's analysis manual).

XFEM is only available in 6.9 and above.