Metal Powder Bed Additive Manufacturing via Electron Beam Melting and Binder Jet 3D Printing

Powder bed additive manufacturing involves layer-by-layer fabrication of desired geometries. Powder bed technologies can be broadly classified as fusion based and inkjet based. Electron beam melting (EBM), and selective laser melting are examples of fusion based powder bed additive manufacturing technologies whereas binder jet 3D printing is an example of inkjet-based powder bed technology. This talk will discuss the key process modalities involved in fabrication of Ti-6Al-4V via electron beam melting along with the binder jet 3D printing efforts at the Manufacturing Demonstration Facility (MDF) of Oak Ridge National Laboratory (ORNL). Typical focus on EBM of Ti-6Al-4V is towards understanding process-microstructure-property correlationships or developing simplified process maps. However, the process has intrinsic and extrinsic nuances such as the operating algorithms and powder feedstock used that can have a significant impact on the properties. These aspects will be presented and discussed in detail. On the other hand, binder jet 3D printing is a non-fusion based technology that involves either infiltration or sintering of powders to attain a final part. This results in some unique microstructures along with cost savings over fusion based technologies. A case study from binder jet 3D printing of Inconel 718 will be discussed.