A non-rigid solid was given a x-direction point load, and von Mises yield criterion is used to check whether the solid would fail or not. I was also asked: "(the previous question asks us to modify the dimensions of the solid and check its von Mises stress) ensures that yielding will not occur in the optimized bracket under the given load. What other failure mechanism could potentially take place?" I plan to use "Tresca yield surface" as my "other failure mechanism". Is this criterion a type of failure mechanism?