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Abstract: Thin films of molybdenum oxides as well as silver molybdates have been deposited by means of double-source pulsed reactive magnetron sputtering. Chemical and phase composition of deposits has been studied by X-ray diffractometry, energy dispersive spectrometry (EDS) and Raman microscopy. Dependent on silver content, three phases, i.e. Ag2 Mo4 O13, Ag2 Mo2 O7 and Ag2 MoO4, belonging to MoO3–Ag2 O binary system, have been identified in the deposited films. It has been shown that silver molybdate films can be easily obtained by subsequent sputter deposition of silver and molybdenum oxide layers at the temperature of 450  C. Single phase Ag2 MoO4 thin films behave very well during dry sliding against alumina ball in the wide temperature range (100–600  C), showing friction coefficient below 0.4. [Copyright &y& Elsevier]

Abstract: Thin films of Mo2N/Ag composites were deposited on steel substrates by the reactive, double source magnetron sputtering. Their structure, chemical and phase composition were examined by X-ray diffraction, EDS/WDS analysis and scanning microscopy. Raman microscopy was used for the local phase identification at the coating surface after high temperature tribological tests carried out up to 400 °C in laboratory air of normal humidity. An addition of silver induced pronounced Mo2N crystallite size refinement accompanied by the slight hardness increase with the maximum at 2.5 at.% of Ag content. An addition of silver led also to the nitride lattice deformation and its partial transformation into β-phase. Except the room temperature tribological tests, where the soft metal addition resulted in an increase of friction, silver plays a positive role manifesting in friction coefficient reduction. After 400 °C friction tests, the silver molybdate phase, Ag2Mo4O13, has been found in the oxide scale covering silver rich (>15 at.% of Ag) composite coatings. Hardness and tribological properties of Mo2N/Ag composite coatings are discussed in terms of their structure and the phase composition. [Copyright &y& Elsevier]

Design concept of novel, wear resistant and low friction nanocomposite materials is based on the formation of two- or multi-phase systems, which show a thermodynamically driven segregation into nanophase with the grain size in nanometer scale. Combination of materials (phases) in the single coating results in new properties, which can meet an increasing level of requirements in modern applications. Thin film, Ti–Si–C system based coatings were deposited from elemental targets (Ti, Si) by double-source reactive, pulsed magnetron sputtering on steel substrates. Their structure, chemical and phase composition as well as pin-on-disc tested tribological properties were studied. [Copyright &y& Elsevier]