Technologies
Understand additive manufacturing's categories, technologies, materials, post-processes and terminology.
Printer Categories
AM's 7 printer category types.
The American Society for Testing and Materials International (ASTM) have defined the seven categories of Additive Manufacturing into which all of the different types fit. These are the recognised industry standard printer category classifications.
Directed Energy Deposition
Directed Energy Deposition (DED) is an AM category which uses a focused energy source, such as a plasma arc laser or electron beam to melt a metal material which is simultaneously deposited through a nozzle. The material stock is either metal wire or powdered metal, which is treated with the focused energy source to deposit material onto a scaffold, build tray or directly on to other objects.
Being mounted on a robotic arm it is possible to use this and a rotatable build platform to minimise the need for support structures.
2 technologies
LMD
Laser Metal Deposition
LMD parts are built on a build plate surface.
WAAM
Wire Arc Additive Manufacturing
WAAM parts are built on a build plate surface.
Advantages
- Directed Energy Deposition can add material to existing parts because it can deposit material from multiple angles.
- It offers a wide selection of inexpensive print material is available, which are also used for welding (This only applies to WAAM).
- It offers a large build area.
- It creates dense, strong parts that have excellent mechanical properties.
- It offers fast build times and minimal material waste.
- It can utilise multiple materials.
Disadvantages
- The hardware is expensive, so has costly initial outlay compared to most other AM processes.
- Support structures are difficult because the large liquid melt pool at the point of deposition doesn’t allow for overhang. This can be overcome by rotating the part.
- The energy required to maintain the melting point creates thermal gradients that can cause residual stress.
- Parts will require post-processing if any dimensional accuracy or good surface finish is required.
AM Environments
Like any machinery, it is important that it and any ancillary equipment are installed, operated and maintained in the appropriate environment.