Strong steels suffer from embrittlement due to dissolved hydrogen, a phenomenon which can be mitigated by trapping the hydrogen at carbide particles, where it is rendered benign. The precipitation and coarsening of plate-like M4C3 carbides during the tempering of quaternary Fe-C-Mo-V martensitic steels has been characterised both experimentally and by developing appropriate kinetic theory. The trapping--capacity is found to peak when the carbides are about 10 nm in length, indicating a role of coherency strains in trapping hydrogen atoms via elastic interactions. This suggests a method for developing alloys which are better able to resist the detrimental effects of hydrogen.
Proceedings of the Royal Society A 462 (2006) 2315-2330.
A short audio interview of Harry Bhadeshia by Mathew Peet on the content of the paper.
Superalloys | Titanium | Bainite | Martensite | Widmanstätten ferrite |
Cast iron | Welding | Allotriomorphic ferrite | Movies | Slides |
Neural Networks | Creep | Mechanicallly Alloyed | Theses | Retained Austenite |
PT Group Home | Materials Algorithms |