|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Grain boundary doping as effective method to improve mechanical properties in ultra-fine grained tungsten
||Daniel Kiener, Michael Wurmshuber, Simon Doppermann, Stefan Wurster, Severin Jakob, Markus Alfreider, Klemens Schmuck, Rishi Bodlos, Lorenz Romaner, Verena Maier-Kiener, Helmut Clemens
|On-Site Speaker (Planned)
Despite its many favorable properties for high-performance applications, tungsten oftentimes cannot tap its full potential due to its inherent brittleness and low formability. Especially ultra-fine grained tungsten, a promising candidate for nuclear fusion applications due to its excellent performance in irradiative environments, suffers from a low-energy intercrystalline fracture. A key factor to reinforce these weak grain boundaries is to increase the grain boundary cohesion, e.g. using doping elements. In this work, several ultra-fine grained tungsten samples, doped with elements that were identified to strengthen grain boundaries via density functional theory, were produced from powders using severe plastic deformation. Extensive microstructural and micro-mechanical characterization confirmed that hafnium and boron can simultaneously increase strength, ductility and toughness of tungsten. Furthermore, an additional heat treatment of the boron-doped sample allows for more grain boundary segregation, which improves the mechanical properties and overall damage tolerance even further, suggesting a pathway to adaptive tungsten alloys.
||High-Temperature Materials, Nuclear Materials, Mechanical Properties