Development of cellular lattice structures for the production of lightweight parts by additive manufacturing

Metal additive manufacturing technologies have the capability to fabricate metal parts with cellular structures directly from the 3D CAD model without any tools. Owing to this, lightweight parts can be manufactured with cellular lattice structures to be used in medical and prosthetics, transportation such as aerospace and aviation vehicles. Cellular lattice structures that resemble to open porous metal foam structures are used for the production of lightweight structures since they have low density. In this study, it is aimed to design lightweight mechanical parts that can be manufactured by additive manufacturing process. For this purpose; new unit cells are developed on CATIA and after defining some inputs (axis, plane, etc.), these unit cells are saved as a template into the catalog file on CATIA. Test specimens, which are prepared to determine the characteristics of designed cellular lattice structures, were manufactured using Direct Metal Laser Sintering (DMLS) technology from cobalt chromium powder and subjected to compression test. In order to investigate the possibility of acquiring lightweight parts with cellular lattice structure and the weights and strengths of the acquired parts, four sample parts are selected and investigated with ANSYS analysis software in terms of equivalent stress, total deformation, and equivalent elastic strain under static load. According to the analysis results obtained with ANSYS, areas of the parts with low stress are made hollow and filled with unit cells with the highest specific strength value, with CATIA software. Comparisons are made between the original part and the part with cellular lattice structure in terms of mass, strength and cost. As a result of this study, it is determined that lightweight parts with sufficient strength can be manufactured by using additive manufacturing technologies and applicability to the mechanical parts is confirmed by finite element analysis.