Please use this identifier to cite or link to this item: https://hdl.handle.net/11147/5004
Title: Magnetic layer formation on plasma nitrided CoCrMo alloy
Authors: Öztürk, Orhan
Okur, Salih
Pichon, L.
Liedke, M. O.
Riviere, Jean Paul
Keywords: CoCrMo alloy
Expanded austenite structure
Ferromagnetism
Plasma nitriding
Magnetoplasma
Publisher: Elsevier Ltd.
Source: Öztürk, O., Okur, S., Pichon, L., Liedke, M.O., and Riviere, J.P. (2011). Magnetic layer formation on plasma nitrided CoCrMo alloy. Surface and Coatings Technology, 205(SUPPL. 2), S280-S285. doi:10.1016/j.surfcoat.2011.01.047
Abstract: In this study structural and magnetic character of the expanded austenite phase (γN) layer formed on a medical grade CoCrMo alloy by a low-pressure Radio-Frequency plasma nitriding process was investigated. The formation of the expanded austenite phase is facilitated at a substrate temperature near 400°C for 1, 2, 4, 6 and 20h under a gas mixture of 60% N2-40% H2. The magnetic state of the γN layers was determined by a surface sensitive technique, magneto-optic Kerr effect (MOKE), and with a scanning probe microscope in magnetic force mode (MFM). Strong evidence for the ferromagnetic nature of the γN-(Co,Cr,Mo) phase is provided by the observation of stripe domain structures and the hysteresis loops. The ferromagnetic state for the γN phase observed here is mainly linked to large lattice expansions (~10%) due to high N contents (~30at.%). As an interstitial impurity, nitrogen dilates the host lattice i.e. the Co-Co (or Fe-Fe) distance is increased, which strongly influences the magnetic interactions. An analogy between the magnetic properties of the expanded phases, γN-(Fe,Cr,Ni) and γN-(Co,Cr,Mo), formed in austenitic stainless steel alloys and the CoCrMo alloy of this study is made, and it is suggested that the ferromagnetic states for the γN-(Co,Cr,Mo) and γN-(Fe,Cr,Ni) phases may be correlated with the volume dependence of the magnetic properties of fcc-Co/Co4N and fcc-Fe/Fe4N, respectively.
URI: http://doi.org/10.1016/j.surfcoat.2011.01.047
http://hdl.handle.net/11147/5004
ISSN: 0257-8972
Appears in Collections:Physics / Fizik
Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Files in This Item:
File Description SizeFormat 
5004.pdfMakale1.26 MBAdobe PDFThumbnail
View/Open
Show full item record



CORE Recommender

SCOPUSTM   
Citations

11
checked on Mar 22, 2024

WEB OF SCIENCETM
Citations

10
checked on Mar 27, 2024

Page view(s)

184
checked on Mar 25, 2024

Download(s)

202
checked on Mar 25, 2024

Google ScholarTM

Check




Altmetric


Items in GCRIS Repository are protected by copyright, with all rights reserved, unless otherwise indicated.