Determination of Anisotropic Mechanical Properties for Materials Processed by Laser Powder Bed Fusion

Autor: Even W. Hovig, Amin S. Azar, Frode Grytten, Knut Sørby, Erik Andreassen
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: Advances in Materials Science and Engineering, Vol 2018 (2018)
Druh dokumentu: article
ISSN: 1687-8434
1687-8442
DOI: 10.1155/2018/7650303
Popis: Improving the success rate in additive manufacturing and designing highly optimized structures require proper understanding of material behaviour. This study proposes a novel experimental method by which anisotropic mechanical properties of additively manufactured materials can be assessed. The procedure is based on tensile testing of flat specimens, manufactured by laser powder bed fusion (LPBF) at different orientations relative to the build plate. In this study, the procedure was applied to the Inconel 718 alloy. Three identical specimen sets were built, each of which received complementary postprocessing treatments. The tensile tests were carried out on specimens with as-built surface finish. Digital image correlation was used to record the strain field evolution on two perpendicular surfaces of the tensile specimens under loading. An optimization algorithm is also proposed for determining the anisotropic elastic constants using only a few tensile test results. It was observed that both build orientation and postprocessing have strong influence on the anisotropic mechanical properties of the material. The effect of microstructure was also investigated and characterised. Consequently, three transversely isotropic compliance matrices were constructed, representing the effect of the different processing conditions.
Databáze: Directory of Open Access Journals
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje