This paper is an important research contribution to the development of PVD coatings, in particular, on ceramic substrates, which, due to their dielectric properties, are difficult materials to coat using this technique. In order to satisfy the desired expectations relating to the PVD coatings, one of the basic properties must be provided for, the adherence to the substrate. The main aim of this research is to investigate the structure and mechanical properties of the coatings deposited in a hybrid process, comprising the atomic-layer deposition (ALD) and cathodic-arc evaporation (CAE-PVD) on sintered carbides and multipoint ceramic cutting tools. The concept of this research study involves an execution and investigation of ALD + PVD hybrid coatings on sintered carbides and a sialon-ceramic substrate, and defining the influence of the ALD interlayer on the adherence of the investigated coatings. The critical load Lc, which is the adhesion measure of coats, was determined with the scratch-test method and a tribological test made with a pin-on-disk tester. Observations of the surface topography and wear mechanism were performed using a scanning electron microscope and atomic-force microscopy. The investigation studies showed that an ALD layer considerably improves the adherence of the PVD layer to the tool-ceramic substrate. The research of the coatings on sintered-carbide substrates showed that the adherence of the PVD coating to the substrate deteriorates in the case of applying an ALD interlayer. Keywords: PVD, ALD, hybrid coatings, tool ceramics, sintered carbideŝ lanek je pomemben raziskovalni prispevek k razvoju PVD nanosov, {e posebno na kerami~ni podlagi, ki je zaradi dielektri~nih lastnosti zahteven material za nana{anje s to tehniko. Da bi zadovoljili pri~akovanja na delu s PVD nanosom, je oprijemljivost na podlago osnovna lastnost, na katero je potrebno biti pozoren. Glavni namen raziskave je preiskati strukturo in mehanske lastnosti nanosa, nane{enega s hibridnim postopkom, ki obsega nanos atomskih plasti (ALD) in katodno izparevanje v obloku (CAE-PVD) na sintrane karbide in ve~to~kovno kerami~no rezilno orodje. Koncept te raziskave vklju~uje izvedbo in preiskavo hibridnega nanosa ALD + PVD na podlago iz sintranih karbidov in sialon keramike ter dolo~itev vpliva vmesne plasti ALD na oprijemljivost preiskovanih nanosov. Kriti~na obremenitev Lc, ki je merilo oprijemljivosti nanosov, je bilo dolo~eno s preizkusom razenja in s tribolo{kim preizkusom trn na plo{~i. S pomo~jo vrsti~nega elektronskega mikroskopa in mikroskopa na atomsko silo je bilo izvedeno opazovanje topografije povr{ine in mehanizma obrabe. Izvedene preiskave ka`ejo, da ALD nanos mo~no izbolj{a oprijemljivost PVD nanosa na orodno keramiko. Pri nanosu na podlago iz sintranega karbida je raziskava pokazala, da je pri uporabi ALD vmesne plasti, oprijemljivost PVD nanosa slab{a.

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This work presents studies of the structure and functional properties of coatings deposited onto indexable inserts made of nitride and sialon tool ceramics with the required properties, i.e. high adhesion, microhardness, high resistance to abrasive and diffusion wear in working conditions of high-performance cuttings tools. In the present paper the results of the investigations of the structure, texture, mechanical and functional properties of the Ti(C,N), (Ti,Al)N, Ti(C,N)+(Ti,Al)N coatings were presented. The 80% increase in the hardness of the coatings in comparison to the substrate material was reported. Test coatings are characterized by good adhesion to the substrate. The maximum lc load of (Ti,Al)N coat applied to the substrate from the nitride ceramics is equal to 42 N. In the studied coatings compressive stresses were found. The results of mechanical properties investigations, especially tribological ones correlate with the results of exploitation tests carried out during the cutting test.

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In the work it was demonstrated that the exploitative stability of edges from tool ceramics and sintered carbides coated with gradient and multilayer PVD and CVD coatings depends mainly on the adherence of the coatings to the substrate, while the change of coating microhardness from 2300 to 3500 HV0.05, the size of grains and their thickness affect the durability of the edges to a lesser extent. It was found that some coatings showed a fine-grained structure. The coatings which contained the AlN phase with hexagonal lattice showed a considerably higher adhesion to the substrate from sialon ceramics rather than the coatings containing the TiN phase. Better adherence of the coatings containing the AlN phase with hexagonal lattice is connected with the same kind of interatomic bonds (covalent) in material of both coating and ceramic substrate. In the paper the exploitative properties of the investigated coatings in the technological cutting trials were also determined. The models of artificial neural network, which demonstrate a relationships between the edge stability and coating properties such as: critical load, microhardness, thickness and size of grains were worked out.Keywords: Tool Materials, PVD and CVD coatings, Surface Treatment, Machining, Artificial Neural Network W pracy wykazano, że trwałość eksploatacyjna ostrzy skrawających z ceramiki narzędziowej i węglików spiekanych pokrytych gradientowymi i wielowarstwowymi powłokami PVD oraz CVD zależy głównie od przyczepności powłok do podłoża, natomiast zmiana mikrotwardości w zakresie od 2300 do 3500 HV0,05, wielkości ziarn oraz ich grubości w mniejszym stopniu wpływają na trwałość ostrzy. Powłoki wykazują drobnoziarnistą strukturę. Powłoki zawierające fazę AlN o sieci heksagonalnej wykazują lepszą przyczepność do sialonowego podłoża niż powłoki zawierające fazę TiN. Lepsza przyczepność powłok zawierających fazę AlN o sieci heksagonalnej związana jest z takim samym rodzajem wiązań międzyatomowych (kowalencyjnych) w materiale powłoki i ceramicznego podłoża. W pracy określono także własności eksploatacyjne powłok w technologicznej próbie toczenia. Zależności pomiędzy trwałością ostrza a własnościami powłok takimi jak obciążenie krytyczne, mikrotwardość, grubość i wielkość ziarna określono z zastosowaniem sztucznych sieci neuronowych.

MoN x O y films were deposited on steel substrates by dc reactive magnetron sputtering. The depositions were carried out from a pure molybdenum target, varying the flow rate of reactive gases. X-ray diffraction (XRD) results revealed the occurrence of cubic MoN x and hexagonal (d-MoN) phases for the films with high nitrogen flow rates. The increase of oxygen content induces the decrease of the grain size of the molybdenum nitride crystallites. The thermal stability of a set of samples was studied in vacuum, for an annealing time of 1 h, for temperatures ranging from 500 to 800 C in 100 C steps. The results showed that pure molybdenum nitride films changed their structure from a meta-stable cubic MoN to hexagonal d-MoN and cubic g-Mo 2 N-type structures with increasing annealing temperatures. The samples with molybdenum nitride films evidenced a good thermal stability, but those with molybdenum oxynitride coatings showed a tendency to detach with the increase of the annealing temperature.

This paper presents the synergy of the effect of two surface engineering technologies—magnetron sputtering (MS-PVD) and atomic layer deposition (ALD) on the structure and properties of 316L steel. Recent studies indicate that PVD coatings, despite their thickness of a few micrometers, have many discontinuities and structural defects, which may lead to pitting corrosion after time. Applying an ALD layer to a PVD coating seals its structure and contributes to extending the service life of the coating. Investigations of the structure and morphology of the produced layers were carried out using a scanning electron microscope (SEM) and atomic force microscope (AFM). In addition, the structure of the coatings was investigated on the cross-section using a scanning-transmission electron microscope S/TEM. The tribological properties of the materials studied were determined by the ball-on-disc method. The corrosion resistance of the tested materials was determined by the electrochemical potentiodynamic method by recording the polarization curves of the anodes. Additional information about the electrochemical properties of the tested samples, including the quality, their tightness, and their resistivity, was obtained by electrochemical impedance spectroscopy (EIS). In addition, the main mechanisms of corrosion and tribological wear were determined by SEM observations after corrosion tests and after tribological tests. The study showed that the fabrication of hybrid layers by MS-PVD and ALD techniques allows obtaining coatings with electrochemical properties superior to those of layers fabricated by only one method.

The article presents the results of research on tribological properties and corrosion resistance of hybrid and individual coatings embedded with the ALD (Atomic Layer Deposition) and PVD (Physical Vapour Deposition) technique on aluminum alloy substrates. Al-Si-Cu alloys coated with hybrid ALD+PVD coatings show significantly higher abrasion resistance compared to uncoated samples. In particular, the TiO2+WC hybrid coating has the highest abrasion resistance. The highest resistance to corrosion is demonstrated by the sample with the TiO2 type ALD coating. As a result of coating, the surface roughness of the tested samples increases, which is related to the occurrence of morphological heterogeneity in the form of solidified drops.The innovative approach of combining several technologies, while simultaneously selecting proper materials and parameters can significantly affect the future and functionality of products obtained. The technique of combining the hybrid coating technology still requires a lot of researches, the results of which can change the meaning and use of new innovative products. Keyword: PVD, ALD, hybrid coatings, TEM, corrosion resistance,