Today's processes for the additive manufacture of metals can be classified according to material feed and energy source:
The most well-known processes today work with a powder bed. In this case, powder layers are generated coat by coat and the component melted in layers. Only a laser or electron beam can be used as an energy source here. Consequently, this is referred to as LBM (Laser Beam Melting) or EBM (Electron Beam Melting).
A carrier gas is required for powder spraying, so using an electron beam as an energy source is not possible. Powder spraying with a laser beam is already in use for additive manufacture under the name LMD (Laser Metal Deposition).
The use of an arc in the form of a plasma beam has been known as plasma powder deposition welding for many years in the field of coating. There are also efforts in additive manufacturing to use this process.
Additive manufacturing processes with wire feed can fundamentally be used with all energy sources mentioned. However, up to now these methods have seldom been found in industrial use.