About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
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Symposium
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Refractory Metals
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Presentation Title |
Grain Boundary Segregation Engineering in Technically Pure Molybdenum Examined via Three-point Bending Tests |
Author(s) |
Severin Jakob, Thomas Weissenboeck, Anton Hohenwarter, Alexander Lorich, Wolfram Knabl, Reinhard Pippan, Helmut Clemens, Verena Maier-Kiener |
On-Site Speaker (Planned) |
Severin Jakob |
Abstract Scope |
Molybdenum has highly advantageous functional and high-temperature properties. However, plastic deformation is limited due to its tendency for brittle, intercrystalline failure, especially at low temperatures. It is well known that segregations have a decisive effect on grain boundary cohesion. An advanced approach for the improvement of the boundaries is segregation engineering, e.g. the deliberate addition of cohesion enhancing elements. To investigate crack formation, three-point-bending tests on recrystallized commercially pure and boron micro-doped molybdenum were conducted between -28°C and RT. The tensile-loaded top surface of the specimens are examined post-mortem close to the final fracture plane via scanning electron microscopy. The occurring, mainly intergranular, separations of grains are investigated for distinct features such as crystallography and length of open boundaries. The chemical composition of the interface is complementary measured by atom probe tomography. Necessary requirements for a direct comparison between the material variants and the effect of boron doping are discussed. |
Proceedings Inclusion? |
Planned: |