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Modeling Friction

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Hello,

I am trying to model a Ti-alloy interlocked diamond in compression. As part of the model, I would like to add the friction between the diamond and a "steel plate", which I made into a rigid body to help with convergence. When I try to run the model with friction, I get the atttached error. I also attached a picture of how I set up the friction. Please let me know any additional information needed to help the model converge.

Thank you! Danny



1 Reply Last Post Jul 20, 2020, 10:54 PM EDT

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Posted: 9 months ago Jul 20, 2020, 10:54 PM EDT

I wanted to add more information to better help with getting some ideas. I attached a picture of the model. There is a contact pair between the steel block and the alumide diamond. The steel block is a fixed rigid body.

The alumide interlocked diamond is fixed on the bottom leg that is not part of the contact pair. The top legs have a downward vertical displacement of 1 mm (~10% total length) applied as a ramp function in .04 increments from 0 to 1.

I have seen issues with both plasticity and friction; the friction will not initialize, and the plasticity seems to fail once it enters the yield stress. I know both the friction and plasticity functions have a decent amount of non-linearities. Are there any suggestions to get the model to approach convergence? The model will converge if neither friction nor plasticity are implemented.

Thanks! Danny

I wanted to add more information to better help with getting some ideas. I attached a picture of the model. There is a contact pair between the steel block and the alumide diamond. The steel block is a fixed rigid body. The alumide interlocked diamond is fixed on the bottom leg that is not part of the contact pair. The top legs have a downward vertical displacement of 1 mm (~10% total length) applied as a ramp function in .04 increments from 0 to 1. I have seen issues with both plasticity and friction; the friction will not initialize, and the plasticity seems to fail once it enters the yield stress. I know both the friction and plasticity functions have a decent amount of non-linearities. Are there any suggestions to get the model to approach convergence? The model will converge if neither friction nor plasticity are implemented. Thanks! Danny

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