Engineering Properties of Cellular Ti-6Al-4V Structures Fabricated by Electron Beam Melting

Abstract:

Cellular Ti-6Al-4V materials with open-cell pore array structures have been fabricated by Electron Beam Melting (EBM) using an Arcam A2X system. The test samples were cylinders 20 mm diam. x 40 mm high, with pore diameters of 1.75 - 2.5 mm and porosities in the range of 61 - 83%. The structures were based on a simple cubic pore array.Sample stiffness and strength were both found to decrease with increasing porosity, exhibiting mean Young’s moduli of 3.5 – 15.6 GPa and mean yield stresses of 20.2 – 93.6 MPa. Finite element analysis (FEA) using ANSYS was performed to model the stress-strain curves for a representative volume, using measured bulk material properties. Stiffness and strength were significantly overestimated by this method, but better agreement with measured data was obtained when the representative volume was extended along the compression axis.

• Periodical: Key Engineering Materials (Volume 704)
• Pages: 318-324
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.704.318
• Online since: August 2016
• Authors: Geoff Smith, Ian Brown*, Alexander Kirchner, Martin Ryan, Peter McGavin, Matt Sharp
• Keywords: Additive Manufacturing, Biomedical, Cellular Materials, Compression Testing, Electron Beam Melting, Porous Materials, Titanium

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