%0 Journal Article 
%A Dominguez-Meister, S.
%A El Mrabet, S.
%A Escobar-Galindo, R.
%A Mariscal, A.
%A Jimenez de Haro, C.
%A Justo, A.
%A Brizuela, Marta
%A Rojas, T.C.
%A Sánchez-López, J.C.
%T Role of Y in the oxidation resistance of CrAlYN coatings
%D 2015
* ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
%X CrAlYN coatings with different aluminum (4-12 at.%) and yttrium (2-5 at.%) contents are deposited by d.c. reactive magnetron sputtering on silicon and M2 steel substrates using metallic targets and Ar/N-2 mixtures. The influence of the nanostructure and chemical elemental distribution on the oxidation resistance after heating in air at 1000 degrees C is studied by means of cross-sectional scanning electron microscopy (X-SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and glow discharge optical emission spectroscopy (GD-OES). The sequential exposure to the metallic targets during the synthesis leads to a multilayer structure where concentration of metallic elements (Cr, Al and Y) is changing periodically. A good oxidation resistance is observed when Al- and Y-rich regions are separated by well-defined CrN layers, maintaining crystalline coherence along the columnar structure. This protective behavior is independent of the type of substrate and corresponds to the formation of a thin mixed (Al, Cr)-oxide scale that protects the film underneath. The GD-OES and XRD analysis have demonstrated that Y acts as a reactive element, blocking the Fe and C atoms diffusion from the steel and favoring higher Al/Cr ratio in the passivation layer after heating. The coating with Y content around 4 at.% exhibited the best performance with a thinner oxide scale, a delay in the CrN decomposition and transformation to Cr2N, and a more effective Fe and C blocking.
%@ 1873-5584
%K CrAlN
%K Magnetron sputtering
%K Oxidation resistance
%K Mechanism
%K Yttrium
doi 10.1016/j.apsusc.2015.06.099
%U http://hdl.handle.net/11556/179
%~ GOEDOC, SUB GOETTINGEN