Experimental validation and microstructure characterization of topology optimized, additively manufactured SS316L components

Publication date: Available online 5 February 2020Source: Materials Science and Engineering: AAuthor(s): B. Rankouhi, K.M. Bertsch, G. Meric de Bellefon, M. Thevamaran, D.J. Thoma, K. SureshAbstractThe integration of topology optimization (TO) and additive manufacturing (AM) has the potential to revolutionize modern design and manufacturing. However, few instances of manufactured optimized designs are documented, and even fewer examples of experimentally-tested designs are available. The lack of validation combined with the influence of AM process on material properties leaves a gap in our understanding of process-microstructure-property relationships that is essential for developing holistic design optimization frameworks. In this work, a functional design was topologically optimized and fabricated using both directed energy deposition (DED) and selective laser melting (SLM) methods. This is the first direct comparison of these AM methods in the context of TO. Mechanical properties of SS316L and the optimized components in as-fabricated and heat-treated conditions were investigated under uniaxial displacement-controlled tensile loading and compared to finite element modeling (FEM) predictions. Optimized samples provided regions of both compressive and tensile loading in the test specimen. Experimental results showed the FEM predictions to be conservative. Microstructural analysis revealed that this difference is due to refined microstructures formed during the additive manuf...
Source: Materials Science and Engineering: A - Category: Materials Science Source Type: research