Phase transformations in nickel sulphide / Oussama Yousfi in Acta materialia, Vol. 58 N° 9 (Mai 2010)  

Phase transformations in nickel sulphide : Microstructures and mechanisms [texte imprimé] / Oussama Yousfi, Auteur ; Patricia Donnadieu, Auteur ; Bréchet, Yves, Auteur . - 2011 . - pp. 3367–3380.
Métallurgie
Langues : Anglais (eng)
in Acta materialia > Vol. 58 N° 9 (Mai 2010) . - pp. 3367–3380

Mots-clés :	Nickel sulphides Phase transformation Microstructure Massive Diffusive
Résumé :	Nickel sulphide inclusions are known to be responsible for delayed fracture in tempered glasses due to phase transformation within the inclusion. Microstructural identification of the phase transformation mechanisms in the Ni–S system close to the NiS composition were carried out on a series of partially transformed states. Observations allow to investigate the morphological evolution during transformation, the phase orientation relationships and the first stages of the transformation were investigated by optical microscopy, electron backscatter diffraction, and scanning and transmission electron microscopy. The transformation mechanisms change significantly with the change in sulphur content of the α-NiS phase. Massive transformation is observed for near-stoichiometric composition. For overstoichiometric composition, the transformation is controlled by a long-range diffusion mechanism. The influence of stoichiometry and impurities (Fe) on the microstructural evolution and transformation mechanisms has also been studied.
DEWEY :	669
ISSN :	1359-6454
En ligne :	http://www.sciencedirect.com/science/article/pii/S1359645410000972