Near-edge X-ray absorption fine structure studies of Cr1−xMxN coatings

Abstract

Near-edge X-ray absorption fine structure studies of Cr 1-x M x N coatings, (2013), doi: http://dx.doi.org/10. 1016/ j.jallcom.2013.06.021 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AbstractCr 1-x M x N coatings, with doping concentrations (Si or Al) varying from 14.3 to 28.5 at.%, were prepared on AISI M2 tool steel substrates using a TEER UDP 650/4 closed field unbalanced magnetron sputtering system. Near-edge X-ray absorption fine structure (NEXAFS) characterization was carried out to measure the aluminum and silicon Kedges, as well as chromium L-edge, in the coatings. Two soft X-ray techniques, Auger electron yield (AEY) and total fluorescence yield (TFY), were employed to investigate the surface and inner structural properties of the materials in order to understand the structural evolution of CrN matrix with addition of Al (or Si) elements. Investigations on the local bonding states and grain boundaries of the coatings, using NEXAFS technique, provide significant information which facilitates understanding of the local electronic 2 structure of the atoms and shed light on the origins of the high mechanical strength and oxidation resistance of these technologically important coatings.

Understanding Local Bonding Structures of Ni-Doped Chromium Nitride Coatings through Synchrotron Radiation NEXAFS Spectroscopy

“…Cr 1– y Ni y N (with y varied from 10 up to 40 at. %) thin film coatings with ∼2 μm thickness have been deposited on AISI M2 tool steel substrates using a TEER UDP 650/4 closed field unbalanced magnetron sputtering technique . A four-target configuration manufactured by Teer Coatings Ltd., Droitwich, Worcestershire, UK, installed at the City University of Hong Kong has been used for this purpose.…”

“…The bonding structural evolution and the spectral changes were correlated in the X-ray absorption near-edge structure (XANES) studies of the aluminum incorporated titanium nitride which afforded a comprehensive treatment on the local atomic structure of TiN. More recently, we presented the bonding structural evolution in CrN coatings upon the progressive incorporation of Al and Si using NEXAFS spectroscopy in order to understand the change in electronic structure as the concentration of dopant varies. Evolution of the bonding structure was identified from shifts in the peaks of Al K-, Cr L-, and Si K-edge absorption energies.…”

“…In a comprehensive review, Chen presented the NEXAFS investigations of transition metal nitrides, carbides, sulfides, and oxides along with other interstitial materials. Meanwhile, there are many attempts at producing new doping materials and improving their novel properties based on findings from the NEXAFS spectroscopy. ,,,− It is clearly evident that modifications of electronic and surface structures of transition metal nitrides remain a focus of research concerning thin film coatings in recent years. It should be noted that, however, the effects of Ni, Al, and Si doping elements on the electronic properties and surface structural evolution and their subsequent roles in modifying the grain boundaries of chromium nitride thin film coatings remain unclear.…”