Electron Beam Reimagined

When the laser reaches its limits: Metal additive manufacturing processes are often unattractive for critical applications due to part distortion, long process times, and excessive material costs. With the newly installed Wayland Calibur3 in the central testing area of the Production Technology Center (PTZ) Berlin, Fraunhofer IPK opens up new avenues for research and development for its partners. The electron beam system is the ideal solution for challenging applications involving difficult-to-weld alloys, strict quality requirements, and intricate geometries.

New solutions for old problems

Researchers can use the new machine to test new solutions for companies in industries that have so far hoped in vain for an additive breakthrough. This is because electron beam processes operate with significantly higher energy efficiency than laser systems and enable more precise temperature control. These are two decisive advantages when it comes to crack-prone or highly reflective materials.

In the process of powder bed fusion by electron beam (PBF-EB), metal powder is selectively melted in a vacuum. It offers the potential of processing even the most demanding materials, including nickel-based alloys, titanium aluminides, and carbides. Up until now, the surrounding powder was sintered in the electron beam process to prevent particles from becoming electrostatically charged and rising in the vacuum. The resulting »sinter cake« makes it difficult to reuse the powder and to produce internal cavities.

The Calibur3 uses patented technology to neutralize the electron beam. The targeted introduction of positively charged ions into the build chamber prevents electrostatic charging, making sinter cakes a thing of the past. This opens up a fundamentally new range of applications for electron beam melting, especially for parts with internal cavities or complex cooling channels, such as those required in turbomachinery or tool technology.

The qualitative aspects of the machining processes are complemented by additional advantages that make the machine a compelling choice for investigating industrial challenges. Its large build space, measuring 300 by 300 by 450 millimeters, allows the electron beam process to produce a high volume of parts efficiently. 
A typical application example, the printing of titanium hip cups, illustrates this point. Today, anyone who additively manufactures such medical implants faces various challenges, including high warpage, expensive material, and limited quantities per build plate. The Calibur3 improves component quality and increases productivity, for example through vertical stacking of components. Instead of 25 hip cups per build job, up to 550 pieces can be produced.  This method saves material, time, and costs without compromising biocompatibility or solidity.

Something for everyone

The machine has many applications beyond medical engineering. When producing gas turbine parts, for example, high-temperature-resistant materials such as nickel-based alloys place extreme demands on the manufacturing process. The Calibur3 allows for precise, consistent processing of these alloys, making it ideal for critical applications that demand safety and long-term stability.

The new machine is also ideal to investigate issues in tool and mold making. Wear-resistant materials or internally cooled tools are difficult to machine and often cannot be printed reliably in the laser process. The Calibur3 guarantees the processing of carbides or high-alloy steels without powder loss thanks to the sinter-free electron beam process.

Additive manufacturing of titanium or nickel-based alloys is central to aviation, whether for engine components or structurally relevant components. The Calibur3 is the only machine that can produce large, complex parts used for instance in aircraft airframes and space propulsion systems without any distortion. Its large build space and precise control of temperature profiles ensure that even thick- and thin-walled structures can be produced in a single job – securely, pre-cisely, and without any need for reworking.