3D printing is usually considered as a layer by layer printing of plastics. Nowadays, this is only one of the varied applications in the field of 3D printing. Today it is possible to print with many different materials, such as metal. Metal printing can be done either with a laser (SLM), electron beam (EBM), wire and arc (WAAM), fused deposition modelling (FDM), binder jetting (BJ) or with nano particle jetting (NPJ). In case of electron beam melting, vacuum is required. Electron Beam Melting is an additive manufacturing method with which it is possible to print material out of titanium, cobalt, chrome alloy, steel, aluminum and copper. This is mandatory for special parts in the aerospace industry or medical market. Examples for printed parts are turbine plates or hip prosthesis.
- Low vibration
- Compact size
- Robust against dust and particles
How does it work?
The Electron Beam Melting system consists mainly of an electron beam column and a formation chamber. In the electron beam column a high power electron beam is generated which is selectively melting the metal powder in the formation chamber. After each layer the system is driving down and a new layer of metal powder is added on top. This process continues until the printing of the part is finished.
The vacuum in the Electron Beam Melting system fulfills several purposes. On the one side it is protective against oxidation and air bubbles. On the other hand it is required to generate the electron beam in the electron beam column and for focusing the beam. The vacuum is avoiding a collision of the electrons with other gas particles which would cause a deflection of the beam. Due to this a high mean free path is required and therefore a low end pressure. Typical final pressures are in the range of 5x10-5 mbar. A fast pump down time is required to minimize the time needed for a part change. Within the process, gases like helium will be injected to ensure a clean and controlled environment. The typical process pressure is therefore in the range of 10x-3 hPa. The vacuum equipment must be insensitive against dust and particles and should have a good resistance to heat.
Pfeiffer vacuum offers a comprehensive portfolio for Electron Beam Melting with vacuum pumps for evacuation, pressure gauges and calibration pumping stations, customized vacuum chambers, as well as leak detectors for the localization of leaks.