Free Contact

For static, nonlinear, frequency, and buckling studies, the program does not impose any restrictions on the relative motion between the contacting areas. For thermal studies, the program prevents heat flow due to conduction through contacting areas. For static and nonlinear studies, the loads can cause interference of components or bodies. Using this option can save solution time if the applied loads do not cause interference. However, the results are invalid if the applied loads cause interference.

Do not use this option for structural problems unless you are absolutely sure that interference will not occur.

You get wrong results if loads cause objects to interfere
Objects do not interfere during loading

The mesh at common areas is not compatible.