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The eleceted stress goal is the overall optimization goal for each optimization and has a big influence on the resulting design. The target is that the material of the part is evenly loaded and the stress is uniformly distributed. Thus, the stress goal isn’t the maximum stress, which can occur at design space limits or due to FE singularities, but the value which is a good middle value for a long part life. Not in every case the yield strength of the material is the best value for this parameter, e.g. when the applied loads are too small to create these result in such stresses. By changing the stress goal the stiffness of the structure can be influenced as well. Due to uniformly distributed stresses, lower stress goals resulting result in stiffer parts at the most lightweight design.
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