ORNL additively manufactures defect-free tungsten components
May 28, 2024
Researchers at Oak Ridge National Laboratory (ORNL), Oak Ridge, Tennessee, USA, are reported to have used electron beam Additive Manufacturing to produce defect-free, complex tungsten parts, suitable for use in extreme environments. The process is expected to have potential for use in clean-energy technologies such as fusion energy.
Tungsten has the highest melting point of any metal, making it ideal for fusion reactors where plasma temperatures exceed 180 million degrees Fahrenheit. In comparison, the sun’s centre is about 27 million degrees Fahrenheit.
In its pure form, tungsten is brittle at room temperature and easily shatters. To counter this, ORNL researchers developed an Electron Beam Powder Bed Fusion (PBF-EB) Additive Manufacturing machine to deposit tungsten, layer by layer, into precise three-dimensional shapes. This technology uses a magnetically directed stream of particles in a high-vacuum enclosure to melt and bind metal powder into a solid-metal object. The vacuum environment reduces foreign material contamination and residual stress formation.
“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.”
