Screw in bone model (modelling questions)

[Izmar]

hi,

I am testing the stresses in bone around screws mechanically drilled in bone. I drew screw and bone block models in Solidworks and then imported the X_T files in abaqus.
I have a few questions on my model:

1- How can I drill the screw hole in the bone block? I used the merge/cut command, is this the right way to do it?
2- Should I mesh the parts separately or the instance as a whole? I tried to mesh the instance but the nodes of the screw and bone were not connected, how can I fix the problem?
3- How do I define the interaction? It is supposed to be rigid mechanical locking without sliding.

Thank you

 

[xerf]

1. If you have an instance for the bone w/out the hole and a instance for the screw you can obtain a new part by using "cut geometry" command in assembly.
2. If you have different part instances they are meshed separately (they do not share nodes.)
3. If there is no relative motion between the two istances (bone and screw) you can define a Tie constraint in the Interaction Module (see Constraints).

Best.

 

[Izmar]

Is there a way to mesh the assembly altogether so that the nodes will be connected? Do they have to be connected anyway or would the Tie constraint solve the problem?

Thanks a lot

 

[Izmar]

I tied the two objects by defining their surfaces and creating a new tie constraint. I did not define any interaction. Now when I apply a concentrated force on the screw, the results show the stress profiles on the screw but nothing on the bone, any idea why?

 

[Izmar]

The tie constraint worked well for me. But now I want to use the surface to surface interaction. I tried to do it but it failed to converge. There are a lot of parameters which I don't really understand, can anyone help me with this model please?