| Abstract Scope |
This presentation will feature several topology optimization methods recently developed for designing functionally-graded lattice infill, support structure, and build orientation for laser powder bed additive manufacturing (AM), in order to address various manufacturability and residual stress/distortion issues. An efficient homogenization-based topology optimization method for optimizing the design of functionally-graded lattice infills in AM components for weight savings and performance enhancement will be presented. The motivation for developing this method is to overcome the inability of conventional topology optimization methods to eliminate overhangs that are not self-supporting in AM. The proposed method takes advantage of the self-supporting nature of lattice structures, as well as the tunable thermal and mechanical properties of lattices by varying their strut size. Next, a support structure design optimization method that reduces residual stress and distortion in an AM build is presented. The key novelty of this method lies in the formulation of the modified inherent strain model which enables fast and accurate prediction of part-scale residual stress and deformation resulting from laser processing. The model reduces simulation time to a matter of minutes from hours/days using other existing methods and thus makes it practical to use topology optimization for AM support structure design. |