For the first time, thin films of NdBaCo_{2}O_{5+x} were deposited by RF magnetron sputtering on different substrates. The films deposited on SrLaAlO_4(001) substrates exhibited highly textured structure with c-axis directed out-of-plane. Magnetic measurements M vs. T of three NdBaCo_{2}O_{5+x}/SrLaAlO_4(001) films revealed successively paramagnetic-ferromagnetic-antiferromagnetic transitions with decrease in temperature. Their paramagnetic Curie-Weiss temperatures were estimated to be in the range of T_{C}=100-116 K. Resistivity of the cobaltite thin film exhibited insulating behavior and the best fit was found for the variable range hopping mechanism.
Two component mixtures of a fluorescent perylene dye (derivative of 3,4,9,10-perylenetetracarboxylic acid) with arachidic acid in the whole range of mole fraction have been investigated in form of molecular monolayers at the air-water interface at different pH of the water subphase. Miscibility of the components in the Langmuir monolayers have been examined for pH 3 and pH 13 of the subphase. Using the Langmuir-Blodgett technique the monolayers were transferred onto freshly cleaved mica sheets and morphology of the films was analyzed using atomic force microscopy working in tapping mode. Investigation of the components miscibility in monolayers, determined by mean molecular area and surface pressure analysis reveals different behavior of the mixtures depending on pH of the subphase. Atomic force microscopy morphology images of the Langmuir-Blodgett films strongly support conclusion about the components mixing and coverage of the mica surface. It has been found that onto acidic subphases components are only miscible in vestigial form, whereas on alkaline the miscibility is strongly affected by the dye concentration.
Hard machining and high speed cutting are challenging machining processes demanded for high productivity for several decades. Hard coatings are mostly used for protection of the tool materials from severe tribological conditions in which excessive cutting temperatures and forces take place during these processes. Oxidation resistance is an important property of the hard coatings in hard machining operations due to high temperatures up to 1000C at the cutting edge. Improvement of oxidation resistance provides longer tool life at dry cutting conditions. TiAlN-based coatings are known to have high oxidation resistance. In this paper, nanolayer AlTiN/TiN coating was deposited on cemented carbide substrates by industrial magnetron sputtering system. The need to understand the effect of nanolayered structure on the oxidation behavior of protective coatings in machining industry in terms of high temperature oxidation tests is the motivation of this investigation. The deposited coating was annealed at 1000C with different durations. Before and after the oxidation tests, the composition, structure and phases of the coating were determined by scanning electron microscopy in combination with energy-dispersive X-ray spectroscopy and X-ray diffraction, respectively. It was found that nanolayered structure improves oxidation resistance, and thereby, it provides longer tool life.
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