FEA Adhesive Modeling

[milio000]

Hello,

I am trying to model an adhesive failure with an instantaneous failure, and the adhesive gets completely delaminated from both surfaces at the same moment. It seems not to fit into the cohesive zone model as there is no failure within the adhesive itself. There is a weld failure model, but I am trying to characterize analytically when the moment of failure for a modified model would happen, and the closest I can get right now is estimating the stress concentration at a failure load in the adhesive, and then extrapolating that to when I see a similar stress concentration in the modified model.

Thank you!

 

[milio000]

Sorry, I forgot to include my question. Would anybody know any techniques to model a bond delamination failure to predict failure loads?

 

[SWComposites]

VCCT and Cohesive Zone models have both been used to predict bonded joint strength. Abaqus has elements for both approaches. You will need test data to a) determine and calibrate the input properties, b) to validate the joint strength predictions.

What are your adherend and adhesive material systems?

 

[milio000]

Adhesive is PMMA cement modeled as solid elements.

And adherends are Cobalt chrome alloy and a bone replica (Saw Bones Foam).

I modified the surface contacts to include a weld failure model parameter for the maximum shear stress when damage initiates.