| Titre : | Conversion of MX nitrides to Z-phase in a martensitic 12% Cr steel |
| Auteurs : | Leonardo Cipolla, Auteur ; Hilmar K. Danielsen, Auteur ; Dario Venditti, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Acta materialia (Vol. 58 N° 2, Janvier 2010) |
| Article en page(s) : | pp. 669-679 |
| Note générale : | Métallurgie |
| Langues : | Anglais |
| Index. décimale : | 669 (Métallurgie) |
| Tags : | TEM XRD Heat resistant steels Nitrides Phase transformation kinetics |
| Résumé : |
A 12% Cr model steel was designed with the purpose of studying the nucleation and growth of modified Z-phase, Cr(V,Nb)N.
The model alloy develops Z-phase after relatively short ageing times and contains only nitrides of Cr, V and Nb. Interferences from the presence of carbides and the development of Laves phase were avoided by keeping the C, W and Mo contents as low as possible. Transmission electron microscopy and X-ray diffraction analysis of extracted particles were used to follow the evolutions of phase composition, phase morphology and phase fraction, particularly of the precipitation of Z-phase, during ageing at 600, 650 and 700°C for up to 103 h. The development of Z-phase appears to be accomplished by the diffusion of Cr atoms into (V,Nb)N particles and their subsequent conversion into cubic or tetragonal Z-phase. Studies at various temperatures indicate that Z-phase development proceeds fastest at 650°C and that Z-phase forms faster at prior austenite grain boundaries. |
| DEWEY : | 669 |
| ISSN : | 1359-6454 |
| En ligne : | http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235556%232010%23999419997%231562200%23FLA%23&_cdi=5556&_pubType=J&_auth=y&_acct=C000070790&_version=1&_urlVersion=0&_userid=6909337&md5=b76b02a9bf437ba6ba8077be7b9830f5 |
