Autori: C.Boursier Niutta, A.Tridello, G.Barletta, N.Gallo, A.Baroni, F.Berto, D.S.Paolino
Rivista: Engineering Failure Analysis
Anno di Pubblicazione: 2022
Abstract:
The significant presence of defects in additively manufactured (AM) components strongly affects the
mechanical performance and must be properly accounted in topology optimization (TO) design in order to
obtain feasible results. In this paper, a generalized formulation of defect‐driven TO for fatigue design, named
TopFat, is proposed. In particular, the first principal stress, that causes the crack propagation, is limited in
accordance with the defect size distribution of the AM process. As the largest defect depends on the final
volume of the component, which changes according to the topology, an iterative procedure is here proposed
where the optimization problem is formulated without imposing volume constraints. The procedure is
implemented in Hypermesh commercial software and applied to an actual aerospace bracket component.
Strength and limitations of the proposed methodology are discussed in comparison with the TO formulations
presented in the literature. Results show that considering the defect population significantly affects the final
topology, while leading to a feasible optimum. Also, even though the computational time increases, an
additional 15% of mass saving is achieved by adopting the proposed iterative procedure with respect to a
volume constraint‐based formulation of TopFat.
DISTRETTO TECNOLOGICO PER L'INGEGNERIA DEI MATERIALI POLIMERICI E COMPOSITI E STRUTTURE