thank you very much that you help me to be sure about my result or if I am going wrongly, show me the correct way. Your help is valuable for me .
I put all the explanation about the simulation process below in images and I will ask my question that I am in doubt about them.
the high of the scaffold is 19.6 mm.

my questions:
what do they mean about the nonlinear mechanical solver? I used static structural with physics performance " mechanical " Is it correct?
What is the difference between " Mechanical" and "nonlinear Mechanical " in physics performance ? I know the mesh setting is a little bit different between them but do they have any effect on the result?
2.I meshed my structure to be close to their number of elements and nodes ( not the same but very close) but I do not know how can I do mesh refinement. I just tried that before to use convergence for von misses stress and put the number for accuracy on 5% but the result did not change( stress changes but very very small). can you guide me about this step? after that, the mesh size did not change and they was the same as before the convergence process and I could not see the min size and max size of the mesh and it seemed all the mesh was the same as the beginning.
3.why do not I have the sharp corner in my stress-strain figure ( my stress-strain curve obtained from Force displacement for the whole body)?
4.In the last image that i attached from the article you can see they did not apply 10% of the height (10%*19.6mm = 0.196 mm) in FEM simulation. for having 0.03 strain we should apply 0.394 mm displacement and 0.196 is related to all the processes in failure up to 0.14 strain. I applied 0.39 in i put END TIME =10, Initial and minimum =100 and max time step 1000. I played with this value but nothing changes and i got the same graph.
5.How did you figure out this is not explicit? could you please explain a little bit?
If you need my settings please let me know to put here to show you maybe I went wrong somewhere.
I got mane errors for previous tries but I solved all of them and convergence goes very well as well. I do not know why there is difference between the elastic part ,
6.I should mention that I did not have tangent modulus ( they did not say anything about that ) and I put it 1.25 GPa from another article. I sent an email to them to give me the value. I hope they answer. Do you think it has effect on the figure ? you think heat treatment that they did for the manufactured structure has an effect on the result of FEM,do I need to do sth special for that in ANSYS ?

Dearalways I wished you answer my questions. and now when I saw your reply :), It was a dream. Realy, Thanks for your help. your time and your help are really worth it to me.
Sincerely yours