Cohesive zone modeling of RTV joint

Hi,

 I am Ghouse, I am working on modeling crack initiation and propagation of RTV (room temperature vulcanization) joint and this joint is present between two automobile engine components. My first question can I use cohesive zone modeling for simulating this problem, If yes, how to get the cohesive traction-separaion properties of this joint. Since this is the real world application which involves bond between a cast iron component and an aluminum component. Can I use the standard test like DCB test or End notched flexure or similar standard test to obtain the traction-spearation curves or the test need to be performed on the actual parts.

 If the standard tests are sufficient than how can we say that the behavior is similar (I mean will it be same fracture toughness etc. for the actual joint).

 Please suggest me on this problem.

 Thanks for you suggestions

Regards

Ghouse Pasha