|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Environmentally Assisted Cracking: Theory and Practice
||Influence of MC Carbides and γ’ on Hydrogen Trapping in Nickel Alloys and Superalloys: Experiment and Alloy Design
||Franck Tancret, Miles Stopher, Edern Menou, Gérard Ramstein, Pedro Rivera-Díaz-del-Castillo
|On-Site Speaker (Planned)
Literature suggests that MC carbides and γ’ with a high γ/γ’ lattice misfit may trap hydrogen in nickel alloys and increase their resistance to hydrogen embrittlement (RHE), although there is no clear evidence of it. Using modelling (Calphad / Thermo-Calc, and data mining to predict lattice misfit) as well as genetic algorithm multi-objective optimisation (GAMOO), alloys are designed containing either only finely dispersed MC vanadium carbides, or only γ’ with a controlled γ/γ’ lattice mismatch. Alloys are produced experimentally and their microstructure is characterised by transmission electron microscopy (TEM) and X-ray diffraction (XRD). After electrochemical hydrogen charging, thermal desorption spectroscopy (TDS) indicates a significant trapping ability of MC and γ’ precipitates. GAMOO is finally used to optimise simultaneously all the relevant chemical and microstructural characteristics; new superalloys are designed, having combinations of good strength, corrosion resistance and RHE.
||Planned: Supplemental Proceedings volume