DED 3D printing systems are also known as LENS (laser engineered net shaping) and DMD (direct metal deposition) machines. Directed Energy Deposition has some similarities to powder bed fusion with a couple of key differences: DED makes use of a mounted laser with a special head that – instead of relying on a bed of powder – projects a mix of metal powder and inert gases to a specific point.
Like PBF, the laser creates a melt pool that fuses the metal powder. Parts can be manufactured using stainless steel, tool steel, titanium, cobalt, chrome and aluminum and a host of others. They can work with metal wire or metal powder and melting can be achieved with a plasma arc, laser, or electron beam. It’s very similar to welding so one of its primary applications is repairing and adding features to existing metal parts.
- Metal wire is the most affordable form of metal 3D printing material
- Some machines can work with two different metal powders to create alloys and material gradients
- 5- and 6-axis motion enables the production of overhangs without the use of support materials
- It’s possible to repair broken metal parts and add new components to objects
- Large build volume
- Efficient material usage
- Parts have high density and good mechanical properties
- Fast printing
- Printed parts have poor surface quality so machining and finishing is usually necessary
- Small details are difficult or impossible to achieve
- High cost of machinery and operation