Researchers at ORNL have achieved a milestone in additive manufacturing by producing the first complex, defect-free tungsten parts. Utilizing electron-beam melting as the process, the research addresses the long-standing challenge of tungsten’s brittleness at room temperature.
Tungsten’s high melting point, the highest of any metal, makes it an ideal material for applications in extreme environments, such as fusion reactors where temperatures can exceed 180 million degrees Fahrenheit. For comparison, the temperature at the center of the sun is about 27 million degrees Fahrenheit. However, pure tungsten’s brittleness has limited its use in such high-temperature applications. ORNL’s electron-beam 3D printing technology mitigates this issue by depositing tungsten layer by layer to form precise three-dimensional shapes.
The electron-beam process involves a magnetically directed stream of particles within a high-vacuum enclosure, which melts and binds metal powder into solid objects. The vacuum environment minimizes contamination and reduces residual stress formation, resulting in defect-free components with complex geometries. This precision and control are crucial for creating components that can withstand extreme conditions without failure.
“Electron-beam additive manufacturing is promising for the processing of complex tungsten geometries,” said ORNL’s Michael Kirka.
“This is an important step for expanding the use of temperature-resistant metals in energy resources that will support a sustainable, carbon-free future.”
This technology is a critical development for expanding the use of temperature-resistant metals in energy applications, particularly in clean-energy technologies like fusion energy. By enabling the production of defect-free tungsten components, ORNL is paving the way for broader adoption of tungsten in sustainable and carbon-free energy systems.
Source: ornl.gov