This paper addresses material nonlinear topology optimization considering the von Mises criterion by means of an asymptotic analysis using a fictitious nonlinear elastic model. In this context, we consider the topology optimization problem subjected to prescribed energy, which leads to robust convergence in nonlinear problems. Two nested formulations are considered. In the first, the objective is to maximize the strain energy of the system in equilibrium, and in the second, the objective is to maximize the load factor. In both cases, a volume constraint is imposed. The sensitivity analysis is quite effective and efficient in the sense that there is no extra adjoint equation. In addition, the nonlinear structural equilibrium problem is solved using direct minimization of the structural strain energy using Newton's method with an inexact line-search strategy. Four numerical examples demonstrate the features of the proposed material nonlinear topology optimization framework for approximating standard von Mises plasticity. KEYWORDS asymptotic analysis, material nonlinearity, nonlinear elastic constitutive model, topology optimization, von Mises criterionNomenclature: y , shear yield stress; y , uniaxial yield stress; , stress tensor; d , deviatoric stress tensor; K, material bulk modulus; , material shear modulus; , strain tensor; d , deviatoric strain tensor; v , volumetric strain; ref , small reference strain; , strain energy density; e , specific strain energy density function of element e; U, strain energy; C 0 , prescribed energy; f 0 , vector of given applied forces; u, nodal displacement vector; , vector of element density variables; , elements' physical densities; r min , filter radius; q, order of filter; p, constant penalty; n, number of elements discretizing the design domain; v e , volume of element e; V max , maximum material volume; T, internal force vector; , reaction load factor; K T , tangent stiffness matrix; D, consistent tangent matrix; Δu, Newton step; , step size by backtracking line search; J, objective function; , Lagrangian function; p lim , limit pressure; w, magnitude of distributed load; , Tikhonov regularization parameter.
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