Gluing and tearing

[Jay102]

Hi,

I would like to model a sandwich of steel-epoxy-PETfilm-epoxy-steel in ABAQUS CAE. Basically, the top edge of the PET film is held/clamped by a steel frame, and I am pulling down the bottom edge of the film to see at which force the PET film tears apart.

1) How do I "glue" two deformables in ABAQUS? Should I treat the small amount of epoxy that sticks the steel and the PET film together a"deformable" and give very high static friction coefficient? (this seems unnecessarily complicated)

2) Is there an option that allows tearing to occur in the post-processing view? Right now I assume tearing occurs when the PET film Mises Stress reaches a certain maximum value, but it would be nice to see "element deletion" at the same time.

 

[vumat721]

I'd probably use cohesive elements to model the Epoxy. If it's reasonably thick, then you can use the "continuum" response option.

Else, if the thickness is negligible and you want to model failure, you can use the "traction separation" response option. You can view the elements that are still active (not failed) in Viewer using their "status" variable, where status = 1.0 means active, and status=0.0 means failed (forget where the setting is in Viewer...)

 

[Jay102]

I have never used cohesive elements; I've been reading through the manual, but I haven't come across an actual tutorial with cohesive elements in CAE.

I've so far created the cohesive section using the Sections Module: Create Secton -> Other -> Cohesive -> Material (chosen) -> Response (Traction Separation) -> Initial thickness (1mm).

Let's say I'm gluing two 1cm x 1cm x 10cm wooden blocks together. How do I use the cohesive section I've just created?

1) Do I assign the faces (to be glued) with the cohesive section ("painting" faces with section property)? Or do I create a 2D thin film from the Part Module, assign it with the cohesive section, place it in between the blocks?

2) When merging, should I merge (Geometry or Mesh?) the two wooden blocks & 2D film (if I model it as a film) with 0 clearance in the Assembly Module?

3) Is contact/contact property used when dealing with glued surfaces? I presume the cohesive modeling would take care of the "stiction" etc. (so it would be infinite friction until cohesive element crack/failure)

Many thanks for your help