Electron beam melting

Electron beam additive manufacturing is a type of additive manufacturing, or 3D printing, for metal parts. Metal powder or wire is welded together using an electron beam as the heat source.

Metal powders can be consolidated into a solid mass using an electron beam as the heat source. This is used as a 3D printing technique, similar to selective laser sintering. This is sometimes called "electron beam melting". EBM technology manufactures parts by melting metal powder layer by layer with an electron beam in a high vacuum. In contrast to sintering techniques, both EBM and SLM achieve full melting of the metal powder.

This powder bed method produces fully dense metal parts directly from metal powder with characteristics of the target material. The EBM machine reads data from a 3D CAD model and lays down successive layers of powdered material. These layers are melted together utilizing a computer controlled electron beam. In this way it builds up the parts. The process takes place under vacuum, which makes it suited to manufacture parts in reactive materials with a high affinity for oxygen, e.g. titanium. The process is known to operate at higher temperatures (up to 1000 °C), which can lead to differences in phase formation though solidification and solid state phase transformation.

The powder feedstock is typically pre-alloyed, as opposed to a mixture. That aspect allows classification of EBM with selective laser melting (SLM) where competing technologies like SLS and DMLS require thermal treatment after fabrication. Compared to SLM and DMLS, EBM has a generally superior build rate because of its higher energy density and scanning method.

Recent work has been published by ORNL, demonstrating the use of EBM technology to control local crystallographic grain orientations in Inconel. Other notable developments have focused on the development of process parameters to produce parts out of alloys such as copper,niobium,Al 2024,bulk metallic glass,stainless steel, and titanium aluminide. Currently commercial materials for EBM include commercially pure Titanium, Ti-6Al-4V,CoCr, Inconel 718, and Inconel 625.

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