Influence of the bilayer thickness of nanostructured multilayer MoN/CrN coating on its microstructure, hardness, and elemental composition

Abstract

Abstract-Multilayer nanostructured coatings consisting of alternating MoN and CrN layers were obtained by vacuum cathode evaporation under various conditions of deposition. The transition from micron sizes of bilayers to the nanometer scale in the coatings under investigation leads to an increase in hardness from 15 to 35.5 GPa (with a layer thickness of about 35 nm). At the same time, when the number of bilayers in the coating decreases, the average Vickers hardness increases from 1267 HV 0.05 to 3307 HV 0.05 . An increase in the value of the potential supplied to the substrate from -20 to -150 V leads to the formation of growth textures in coating layers with the [100] axis, and to an increase in the intensity of reflections with increasing bilayer thickness. Elemental analysis carried out with the help of Rutherford backscattering, secondary ion mass spectrometry and energy dispersion spectra showed a good separation of the MoN and CrN layers near the surface of the coatings.

Preparation and Characterization of the Cr-Nanodiamonds/MoN Coatings with Performant Mechanical Properties

“…The studies carried out proved that the synthesized coatings of γ-Mo 2 N at a nitrogen pressure of 0.4 Pa on HSS substrates had a hardness of 3372 ± 100 kg/mm 2 [53]. When obtaining the CrN and γ-Mo 2 N phases of the MoN/CrN coating with a cubic lattice, a maximum hardness of 35.5 GPa was observed [22].…”

“…It has been reported in the literature that a multilayer Si-MoSi 2 coating structure consisting of molybdenum can improve the thermal resistance, corrosion resistance and mechanical properties of a coating [19,20]. Combinations of chromium and molybdenum nitrides have been shown to have the best characteristics [21][22][23].…”

Nanocomposite Multilayer Binary Nitride Coatings Based on Transition and Refractory Metals: Structure and Properties

“…Increasing the bias voltage to −150 V led to the formation of the [111] texture and the solid solution (Cr,Mo)N at interfaces between layers. Applying the highest bias voltage (−300 V) resulted in the [200]-oriented structure due to the relative decrease of the nitrogen content[100,126,128,129]. Peak shift towards lower angles indicated residual stresses, which might be caused by the deposition conditions, as well as the differences in thermal expansion coefficients and temperature of the substrate and the coating during the fabrication process[130,131].…”

Multilayered vacuum-arc nanocomposite TiN/ZrN coatings before and after annealing: Structure, properties, first-principles calculations

“…A varying the deposition conditions, such as gas pressure in the deposition chamber, bias potential, bilayer thickness, etc. allows to fabricate coatings with very high hardness [9][10][11], good wear coefficient and resistance to wear, oxidation [12][13][14][15][16][17] and to corrosion [18,19] as well as with good electrical properties [20,21]. As it was reported in the previous papers [22,23], coatings on the (Ti,Zr)N base have high hardness 42-48 GPa, as well as resistance to oxidation under the influence of high temperatures 1170°С [24][25][26][27][28].…”