ملخص: Low temperature plasma assisted nitriding (PAN) treatments of Inconel 690 (a nickel base alloy with a 30 wt.% chromium content) produce a complex layer constituted by two different metastable f.c.c. solid solutions denoted ([gamma]N1 and [gamma]N2). In addition, different layer thicknesses are observed for differently oriented grains. Reactive magnetron sputtering (RMS) of Inconel 690 in argon-nitrogen containing mixtures is used to produce homogeneous films constituted by a well defined [gamma]N phase. In reactive conditions, the as-deposited coatings (TN) with a grain size lying between 3 and 7.5 nm. A comparison between the products synthesized by these two techniques (PAN and RMS) is presented in this study. The formation of [gamma]N phases in low temperature PAN is discussed in the light of electron backscatter diffraction measurements and by comparison with X-ray diffraction patterns of RMS coatings. By using the results obtained in situ by RMS on heated substrates and by tempering of as-deposited films, the decomposition products of the [gamma]N phase at high temperature ([ges]450 [deg]C) or long PAN treatments at 400 [deg]C are identified to be f.c.c. CrN and [gamma](Ni,Fe) depleted in nitrogen.

لغة: إنجليزية