Minimizing creep deformation via topology optimization

In this study, we propose a new topology optimization problem for creep deformation minimization. It is a phenomenon in which deformation progresses even when the load is constant, and is a cause of damage to mechanical parts. Therefore, the results of this paper will be one of the solutions to the problem of creep deformation. We deal with a viscoelastic model assuming the generalized Maxwell model to account for creep deformation. In addition, we devise a new objective function that directly evaluate the creep deformation. Since sensitivity analysis of the objective function is necessary for topology optimization, we formulate the sensitivity of the viscoelastic model to accurately consider the time dependence. The relationship between the creep characteristics and the objective function is explained through a numerical example using a one-dimensional model. By examining a two-dimensional model, it is shown that the formulated sensitivity is validated and the proposed method derives the optimized configuration under which creep deformation is minimized.