Advanced metal powder based manufacturing of complex components by electron beam melting

Abstract Electron beam melting of Ti–6Al–4V powder (∼30 μm diameter) to create complex, three-dimensional components layer by layer using CAD is described along with the characterisation of these products (builds) by optical and electron microscopy, and mechanical testing. Build defects, including porous (unmelted or unsintered) zones, inclusions and gas bubbles trapped in the atomised powder particles and retained in the build, are illustrated. Reticulated mesh geometries and their applications are described along with examples having biomedical applications. Microstructures of solid components and mesh arrays are described. Powder chemistries and solid build chemistries are also examined and shown to be constant for up to 40 cycles of powder reuse, but there was a 10–15% reduction in Al content in the solid builds at optimised build conditions. Quality control and related issues are also described using duplicate products for destructive testing correlated with removable quality control tabs on the builds.

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