Powder characterisation and the impact on part performance in electron beam melted Ti6Al4V

Abstract

Metallic powder for Additive Manufacturing (AM) typically varies between different batches, while being supplied to achieve the same customer specification. In order to reduce this variation and minimise waste, batches are often mixed together in both their virgin and used form. However, the properties of bulk components must have limited variance in order to be reliably used in an industrial setting. This manuscript is focused on the analysis of Grade 5 Ti6Al4V powders (3 virgin, plus 2 blends) and the associated mechanical properties of Electron Beam Melted (EBM) AM specimens. Measurements were performed in accordance with the principles defined in the MMPDS Handbook, ESDU database, and ASTM F2924. The tensile, and fatigue properties of the EBM specimens were found to be superior when compared with Ti6Al4V properties within these standards. This demonstrated that these powders are suitable for a wide range of commercial applications, and that these blended powders (including used powders) are able to achieve these requirements. Additionally, the results provide a systematic route for powder verification and highlight the importance of adhering to standardised principles and specifications to ensure quality and reliability in metallic AM materials.

Keywords

• Ti6Al4V
• Electron beam melting
• Additive manufacture
• Microstructure
• Tensile properties
• fatigue performance