Tungsten Wire—From Lamp Filaments to Reinforcement Fibers for Composites in Fusion Reactors

• Published in: Advanced engineering materials Vol. 26; no. 19
• Main Authors: Riesch, Johann, Fuhr, Maximilian, Almanstötter, Jürgen
• Format: Journal Article
• Language: English
• Published: 01.10.2024
• Subjects: composites; fiber‐reinforcement; lamp filaments; nuclear fusion; tungsten; wire
• ISSN: 1438-1656; 1527-2648
• DOI: 10.1002/adem.202400951

The use of drawn tungsten wire marked a breakthrough in electric lighting which led to a significant advancement in human society and technology. Nowadays, thermal light sources using tungsten filaments are being more and more replaced by semiconductor‐based light‐emitting diodes (LEDs). Despite the lower visibility of incandescent lamps in everyday life, new markets and applications for drawn tungsten wires are opening up, which makes this complex material a highly‐studied subject. One of these applications is the use of heavily drawn tungsten wires as high‐performance reinforcement fibers for new composites that can withstand the extreme environment present in a nuclear fusion reactor. The main advantage of tungsten wires for this class of composites is their ductility and high strength. The wires can be used to increase the high‐temperature strength of copper‐based heat sink materials as well as the fracture toughness of bulk tungsten considered for the use of highly loaded reactor wall components. These new applications for tungsten wire have also given new impetus to the study of their fundamental properties. The article retraces the development of drawn tungsten wires from the application as filament material in incandescent lighting to its use as reinforcement fibers for advanced composites in nuclear fusion. Highlights are the materials science reasons for the wires’ unique mechanical properties and an outlook into the potential “second life” in advanced composites compared to their “first life” in lighting.