What is Electron Beam Melting (EBM)?
What is Electron Beam Melting (EBM)?
Electron Beam Melting (EBM) is a 3D manufacturing process in which a powdered metal is melted by a high-energy beam of electrons. An electron beam produces a stream of electrons that is guided by a magnetic field, melting layer upon layer of powdered metal to create an object matching the precise specifications defined by a CAD model. Production takes place in a vacuum chamber to guard against oxidation that can compromise highly reactive materials. Electron Beam Melting is similar to Selective Laser Melting (SLM), as they both print from a powder from the 3D printer’s powder bed, but EBM uses an electron beam instead of a laser.
EBM builds high-strength parts that make the most of the native properties of the metals used in the process, eliminating impurities that may accumulate when using casting metals or using other methods of fabrication. It is used to print components for aerospace, automotive, defense, petrochemical, and medical applications.
EBM Printing Advantages and Disadvantages
Electron beam melting technology is proprietary and EBM printers require skilled technicians to run them. Though EBM can be much faster than SLM (selective laser melting), SLM produces smoother, more accurate parts.
History of EBM Printing
In 1993, Arcam collaborated with Chalmers University of Technology in Gothenburg in filing an application for a patent on the principles of EBM. The process was developed with the goal of creating 3D objects by melting an electrically conductive powder, layer by layer, with an electric beam. In 1997, Arcam AB was founded and the company has continued to develop EBM and commercialize EBM printing.
FAQ
What is the difference between electron beam melting (EBM) vs selective laser melting (SLM)? Electron Beam Melting is similar to SLM in that they both print from a powder from the 3D printer’s powder bed, but EBM uses electrons rather than the photons used in the SLM process. In EBM, a high-energy electron beam melts layers of powdered metal to create a form within a vacuum. In SLM, a laser beam emitting photons bonds or sinters layers of powdered metals to solidify the metal. SLM does not require a vacuum environment.
What temperatures are required for EBM? As EBM often is used on metals with a high melting point, temperatures as high as 2,000 degrees Celsius have been measured in the electron beam melting process.
Why does the EBM process take place in a vacuum? Treating metals at a high heat tends to increase oxidation which can make the final product brittle. Since the EBM process takes place in vacuum, allowing for a high temperature in a non-oxygenated environment, it relieves internal stresses and resulting in more resilient, flexible parts.
How does an electron beam gun work? An electron beam gun has a tungsten filament that, when superheated, emits a stream of electrons that, in a vacuum, accelerate to roughly half the speed of light.
Can EBM be used on plastics, metals and ceramics? Since EBM relies on electrical charges and extremely high temperatures, it can only be used on conductive materials like metals.
Which is the better choice for rapid prototyping: SLS or EBM? Because an electron beam is wider than a laser beam, EBM may produce a less precise part than SLS but is faster in producing larger objects.