Showing results for 
Search instead for 
Did you mean: 

SOL601-106 ATS with contact yields in large strains and very distorted element

Gears Phenom Gears Phenom
Gears Phenom

Hello experts,


I have a problem with an analysis with large displacements / strains in solution 601-106.

- isotropic material behaviour

- linear heaxeder elements

- symmetrical constraints for quarter modeling

- surface to surface contact


In my model I press a kind of stamp (solid) onto a solid plate with high pressure a I want to get it deformed in a very strong way with buckling and so on.

Everything works fine until I increase my pressure.

I 've got a distorted element in contact zone with large strains. The element penetrate itself with a strain of nearly 32 % compression. Otherwise the next element in vertical direction above contact zone shows a strain of positive tension in vertical direction.

Only the utmost element layer is compressed, the next is not. I expected that compression would procceed through element layers.


If I analyze other incrementation steps earlier, I could see that the effect is growing but not from the early beginning.


I've got the following error message:


Element distorted, Jacobian DET= -1.138862E-01  GROUP=        2  EL=    200830


And that is true.

Here some pictures:


1. Overlay plot of deformation during load incrementation (deformation scaling 1.00 absolute)


2. nonlinear strain component zz of compression zone of stamp (source region) at the end of aborted analysis:



Now my question:

Is this a limitation of solution 601 or may be an error in my model?

I' ve found a statement in help-documentation that acceptable maximum strains in solution 601 are nearby 30 %.


Is this limitation induced by such deformation effects or vice versa?

It looks for me as there is something like hourglass - deformation.

Does anybody know the internal relationships of NX and can help?

Could I change parameters for contact or NXSTRAT to improve the solution?


Any suggestion is welcome.

Best regards,


| Production: NX10; Development: VB, TCL/TK, FORTRAN; Testing: NX11 | engelke engineering art GmbH, Germany
| Kudos for good posts! And if my post answers your question, please mark it as an "Accepted Solution".