Dynamic Mechanical Response of Additive Manufactured Ti-6Al-4V

The dynamic mechanical response of additive manufactured (AM) Ti-6Al-4V has been investigated via Split-Hopkinson Pressure Bar (SHPB) and single-stage gas gun plate-impact experiments. Rods of Ti-6Al-4V were manufactured from Arcam and Renishaw electron beam melting (EBM) and laser melting deposition (LMD) powder bed systems, respectively. Horizontal and vertical build directions were produced for plate impacts to determine any effect of build layers on dynamic tensile strength. The as-received microstructures were characterized via optical microscopy and electron backscatter diffraction (EBSD). Johnson-Cook constitutive model parameters were found for the EBM condition via SHPB experiments. Plate impacts producing nominal peak shock stresses near the theoretical tensile strength of the material (3-5 GPa) were conducted to study incipient spall damage conditions as a function of AM material condition.