How to have a correct result of simple static tensile analysis?

Hi all

 I have tried in the last few weeks to perform a simple static analysis of Tensile on a 10*20*100 Beam on Catia V5, but every time  I get a wrong stress value (normally I should have 5 MPa).
even the position of the constraints on the result is incorrect.

 

Thank you for any help or remarks


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