Instrumented Impact Testing of Miniaturized Charpy Specimens of AM Ti-6Al-4V

摘要

An investigation on the impact toughness properties of wrought and additively manufactured (AM) Ti-6Al-4V was conducted at National Institute for Standards and Technology (NIST) Boulder by means of instrumented impact tests on miniaturized Charpy specimens. Full transition curves for absorbed energy and lateral expansion were obtained by performing tests in the temperature range between −196°C and 700°C. The effect of various parameters was investigated for AM specimens, namely specimen orientation, hot isostatic pressing (HIPing), and notch configuration (printed or machined). Our results indicate that AM specimens exhibit equivalent or better impact toughness than wrought material after HIPing and that the material is more resistant to cracks growing in the plane perpendicular to the build direction than in the plane containing the build direction. HIPing has a significantly beneficial effect for the AM material, while no effect of notch configuration was observed from the results obtained.