Effect of Process Parameters and Build Orientation on Microstructure and Impact Energy of Electron Beam Powder Bed Fused Ti-6Al-4V

Autor: Spencer Jeffs, Robert Lancaster, Gareth Davies, William Hole, Brenna Roberts, David Stapleton, Meurig Thomas, Iain Todd, Gavin Baxter
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Materials, Vol 14, Iss 18, p 5376 (2021)
Druh dokumentu: article
ISSN: 1996-1944
DOI: 10.3390/ma14185376
Popis: To fully exploit the benefits of additive manufacturing (AM), an understanding of its processing, microstructural, and mechanical aspects, and their interdependent characteristics, is necessary. In certain instances, AM materials may be desired for applications where impact toughness is a key property, such as in gas turbine fan blades, where foreign or direct object damage may occur. In this research, the impact energy of a series of Ti-6Al-4V specimens produced via electron beam powder bed fusion (EBPBF) was established via Charpy impact testing. Specimens were produced with five different processing parameter sets, in both the vertical and horizontal build orientation, with microstructural characteristics of prior β grain area, prior β grain width, and α lath width determined in the build direction. The results reveal that horizontally oriented specimens have a lower impact energy compared to those built in the vertical orientation, due to the influence of epitaxial grain growth in the build direction. Relationships between process parameters, microstructural characteristics, and impact energy results were evaluated, with beam velocity displaying the strongest trend in terms of impact energy results, and normalised energy density exhibiting the most significant influence across all microstructural measurements.
Databáze: Directory of Open Access Journals