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1

The inﬂuence of Kanthal wire surface defects on the formation of Si nanolayer deposited by PVD method

Szczypiński M., Reszka K., Szczypiński M. M.

Materials Science Poland

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2018

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Vol. 36, No. 2

264--269

EN

The subject of this research is the structure of a Si nanolayer deposited on a FeCrAl wire surface by means of magnetron sputtering method. Si layer was selected as one of possible protections of the wire surface against excessive corrosive-erosive wear. In order to increase the power necessary for the DC discharge of the magnetron with Si cathode, a second magnetron with an aluminum disc as a cathode was used. The wire was attached to a carousel holder to ensure its rotation around the magnetron. The thickness of the deposited layers was about 150 nm. A wire surface examination indicated the presence of defects such as gaps between grains, cavities as well as severely deformed grains of surface layer. The research was conducted on the sample sections which had been prepared by focused ion beam method (FIB). The technique of transmission microscopy, which was used for observation, allowed us to obtain images in bright field (BF), dark field (DF), as well as in high resolution (HREM). The studies were also performed on the wire surface after the cutting process of the expanded polystyrene blocks. A metallographic optical microscope Nikon MA200 with a large depth of field was used for the examination which showed the presence of carbon deposit products. Additionally, a composition microanalysis was carried out along the line within selected areas of samples, with the use of energy dispersive spectroscopy (EDS). A large impact of wire surface defects on Si layer forming was found as well as a high direct homogeneous growth. The examination of the sections indicated the existence of a mechanism of defects sealed by Si layer, where directionality of grains growth in these areas revealed the tendency for vertical location relative to defects surface. Consequently, closed nanopores, i.e. spaces not covered with Si layer, were created. It is a characteristic feature of areas with defects covered with an oxide film created in a natural way.

2

Structure and corrosion resistance of Co-Cr-Mo alloy used in Birmingham Hip Resurfacing system

Dobruchowska E., Paziewska M., Przybyl K., Reszka K.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 2

31--39

EN

The endoprostheses made of cobalt-chromium-molybdenum (Co-Cr-Mo) alloys belong to the group of the most popular metallic implants used for hip joints reconstruction. For such biomaterials, the primary goal is correct and long-term functioning in the aggressive environment of body fluids. Therefore, the purpose of this study was to examine both the morphology and the corrosion resistance of implants made of the cobalt alloy used in Birmingham Hip Resurfacing (BHR) system (Smith & Nephew). For comparative purposes, the electrochemical studies were done for the nitrided stainless steel – Orthinox. Methods: Observations of the microstructure of the investigated material were performed by means of the optical metallographic microscope and the scanning electron microscope. Furthermore, Energy Dispersive X-ray Spectroscopy was used to analyse the chemical composition of the endoprosthesis. Characterisation and evaluation of electrochemical corrosion resistance of the selected alloys were performed by potentiodynamic polarisation tests. Results: The structural studies confirmed that Co-Cr-Mo (BHR system) is characterised by a typical dendritic microstructure with carbide precipitates, mainly M23C6, within the interdendritic areas. Results of the polarisation measurements showed that the investigated cobalt alloy exhibits lower corrosion potential than Orthinox in the utilised environments (3% NaCl, simulated body fluid – Hank’s Body Fluid). Conclusions: However, the high passivation ability of the Co-Cr-Mo alloy, as well as its resistance to the initiation and propagation of localised corrosion processes, indicate that this material is significantly more appropriate for long-term implants.

3

Analiza przyczyn uszkodzeń drutu elektrorezystancyjnego do cięcia bloków ze spienionego polistyrenu (EPS)

Rydzkowski T., Szczypiński M., Reszka K., Michalska-Pożoga I., Mitura K., Szczypiński M., Klepka T.

Inżynieria i Aparatura Chemiczna

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2016

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Nr 3

106--107

PL

Przedstawiono analizę wyników badań oraz doświadczeń produkcyjnych dotyczących problematyki cięcia bloków spienionego polistyrenu EPS. Stwierdzono, że niewłaściwe materiały i parametry eksploatacyjne urządzeń mogą prowadzić do znacznych strat materiałowych i ekonomicznych. Analiza zebranych danych wykazała, że dobór właściwego drutu oporowego oraz parametrów jego pracy ma kluczowe znaczenie dla efektywnego działania urządzeń do cięcia bloków z EPS. Wbrew oczekiwaniom, zerwanie drutu zwykle nie wynikało z przetopienia. Do przerwania dochodziło głównie na skutek rozciągania, któremu towarzyszyło utlenienie się drutu.

EN

Research results and production experiences dealing with foamed polystyrene (EPS) blocks cutting are presented. Unsuitable materials and operating parameters of equipment can lead to substantial material and economic losses. Analysis of collected data shows that the selection of proper resistance wire and parameters of its work are essential for the effective operation of EPS cutting machines. Contrary to expectations, breaking the wire was usually not the result of wire melting. The wire ripping occurred mainly due to the stretching accompanied by wire oxidation.

4

Morphology and Electromagnetic Shielding Effectiveness of PP Nonwovens Modified with Metallic Layers

Koprowska J., Dobruchowska E., Reszka K., Szwugier A.

Fibres & Textiles in Eastern Europe

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2015

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Vol. 23, no. 5 (113)

84--91

EN

Polypropylene (PP) nonwoven was used as a substrate for CuSn and CuZnNi deposited layers. Nonwoven metallization was carried out using the DC magnetron sputtering process at various process parameters (e.g. effective power dissipated in the target, velocity of the substrate drift, number of cycles). The studies aimed at defining the surface morphology of PP nonwoven modified by metallic deposition, the crystallographic structure of the thin metallic layers and the effect of the layers’ crystallinity on the electromagnetic (EM) shielding effectiveness of the two-component metal/PP composites. The morphology studies were covered by scanning electron microscopy. Furthermore the crystalline character of components CuSn and CuZnNi was examined in grazing-incidence angle X-ray diffraction experiments. It was found that CuSn/PP composites with a crystalline structure of the metallic layer exhibit the highest values of shielding effectiveness (44-45 dB at 27,12 MHz and 38-39 dB at 1795 MHz).

PL

Do napylania warstw CuSn i CuZnNi jako podłoże (substrat) użyto włókninę polipropylenową (PP). Metalizację włókniny prowadzono stosując proces rozpylania magnetronowego DC przy różnych parametrach procesowych (takich, jak na przykład: moc efektywna wydzielana na targecie, prędkość przesuwu podłoża, ilość cykli). Badania miały na celu określenie: morfologii powierzchni włókniny PP modyfikowanej przez osadzania metali, krystalograficznej struktury cienkich warstw metalicznych i wpływu efektu krystalizacji warstw na skuteczność elektromagnetycznego (EM) ekranowania dwuskładnikowych kompozytów metal/PP. Badania morfologiczne zostały wykonane za pomocą skaningowego mikroskopu elektronowego. Ponadto, krystaliczną postać CuSn i CuZnNi składników i skład fazowy warstw metalicznych osadzonych na podłożu z włókniny polipropylenowej oceniano w oparciu o pomiary dyfrakcji rentgenowskiej. Stwierdzono, że kompozyty CuSn/PP o strukturze krystalicznej warstwy metalicznej wykazują najwyższe wartości skuteczności ekranowania (44 - 45 dB przy 27,12 MHz i 38 - 39 dB przy 1795 MHz).

5

Characterization of Alumina Scale Formed on FeCrAl Steel

Reszka K., Morgiel J., Żurek Z., Jaroń A.

Archives of Metallurgy and Materials

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2014

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Vol. 59, iss. 1

77--81

EN

In this paper the morphology of the oxide scale formed at 850°C on the foil surface of FeCrAl steel is described. Two types of samples have been used: one covered with an Al nano-layer and the second without. Microscopic observations of the cross-sections of scales have demonstrated that in the case of foil without Al nano-layer there is a remnant of an amorphous Al2 O3 nano-layer, from which γ and θ crystallites of Al2 O3 have been grown. In the case of foil covered with the Al nano-layer, α- Al2 O3 phase is present and θ-phase forms a forest of whiskers on the surface.

PL

W pracy opisano morfologię warstw tlenkowych, które powstały na folii FeCrAl pod wpływem jej utleniania w temperaturze 850°C Badania dotyczyły folii pokry tej nanowarstwą Al oraz nie pokrytej. Przekroje warstw i podłoża stalowego badane za pomocą transmisyjnej mikroskopii elektronowej wykazały, że w przypadku folii nie pokrytej warstwą Al występuje pozostałość amorficznej nanowarstwy Al2 O3 . z której następuje wzrost krystalitów γ i θ Al2 O3. W przypadku folii z osadzoną nanowarstwą Al stwierdzono obecność fazy α- Al2 O3 oraz występującej na powierzchni folii fazy θ Al2 O3, w postaci lasu whiskerów.

6

Surface modification of polypropylene nonwoven with composite metallic layers

Reszka K., Dobruchowska E., Koprowska J., Wiśniewski B.

Journal of KONES

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2012

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Vol. 19, No. 4

539-547

EN

Polymer fibres have the great potential for application due to their large surface area relative to volume, incomparably large length relative to the cross-section, high strength and ease of forming the nonwovens in thermal processing. Due to the specific properties of textiles, they are applied, among others in the manufacture of filters, sensors, biomedical devices and protective clothing. This study was aimed to evaluate the surface morphology of polypropylene nonwoven modified with metallic layers CuSn, CuZnNi, NiCuFe, deposited by the magnetron sputtering technique. There was also carried out a qualitative and quantitative analysis of deposited thin layers and their compositions were compared with compositions of targets used for magnetrons. The surface morphology was tested using the metallographic optical microscope with a CF160 optical system and the scanning electron microscope adapted to work in an environmental mode. A study of composition was based on a microanalysis using the energy dispersive X-ray radiation deriving from the excited atoms (EDS).

7

Morfologia warstw Al2O3 utworzonych na folii FeCrAl poddanej procesowi wysokotemperaturowego utleniania w atmosferze mieszaniny Ar/O2

Reszka K., Morgiel J., Żurek Z.

Ochrona przed Korozją

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2011

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nr 6

355-358

PL

W pracy przedstawiono wyniki badań morfologii warstwy tlenkowej utworzonej na powierzchni folii stali ferrytycznej typu FeCrAl utlenianej w mieszaninie Ar + 67,6% O2 w temperaturze 850oC. Badania utleniania prowadzono na dwóch rodzajach folii: pokrytych nanowarstwą Al oraz niepokrytych nanowarstwą Al. Obserwacje mikroskopowe przekrojów warstw zgorzeliny wykazały, że w przypadku folii niepokrytej nanowarstwą Al istnieje pozostałość amorficznej nanowarstwy Al2O3, z której wyrastają krystality ?- i ?- Al2O3. W przypadku folii pokrytej nanowarstwą Al nie stwierdzono obecności nanowarstwy amorficznej tlenku i fazy ?- Al2O3. Stwierdzono natomiast istnienie bezpośredniego kontaktu kryształów ?- Al2O3 z podłożem metalicznym. Faza ?-Al2O3 występuje na powierzchni metalicznego rdzenia jak również wewnątrz zgorzeliny. ?- Al2O3 również występuje w postaci whiskerów.

EN

The present study deals with characterization of scale morphology formed on foil steel FeCrAl in Ar + 67,6% O2 at 850oC. Studies were carried out on two different samples of steel: non covered nanolayer of Al and covered nanolayer Al. The use of scanning electron microscopy SEM and transmission electron microscope TEM could help the identification of transient phases. ?- and ?- Al2O3 phases were identified on the metal core. ?- Al2O3 formed columnar crystal within scale, which form whisker on the surface of the scale. ?- Al2O3 was identified on the scale/metal interface and on the surface of scale in whisker shape.

8

An application of artificial neural network to exhaust emission modelling from diesel engine

Reszka K., Rakoczy J., Morgiel J.

Journal of KONES

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2011

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Vol. 18, No. 2

365-367

EN

Processes of the combustion of liquid fuels and solid are more complex than combustion of fuel gases. With reference to liquid fuels occur additionally processes of vaporization of the fuel, and with reference to solid fuels - decomposition of the solid phase with processes of melting and vaporization, pyrolysis, or gasification. This simultaneous and also different influence of different parameters is sometimes a reason of incorrect interpretation of experimental results. The study of the theoretical model of the combustion process concerning of liquid and solid fuels and which then the model takes into account also the gas- phase, because combustion processes take place in this phase, and occurs the interaction of the phase gas- and liquid or the solid one. The theoretical model is presented basing on experimental initial researches realized in a model with reference to liquid fuels and solid ones. Researches realized in the constant volume chamber with measurements of the pressure during the process of the combustion with the use of quick photography and with measurement of the distribution of the velocity in the spray of the fuel and droplet measurements by means the laser Doppler equipment LDV and PDPA. There were obtained a good agreement of findings experimental researches with the theoretical model. Generally on the combustion velocity of liquid fuels and solid one significant influence has a kind (laminar, temporary and turbulent) and the thickness of the thermal boundary layer.

9

Badania warstwy tlenkowej w procesie wysokotemperaturowego utleniania folii FeCrAl

Murzyński D., Rakoczy J., Reszka K.

Chemik

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2009

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Vol. 62, nr 1

11-13

PL

Urządzenia katalityczne, które znajdują zastosowanie w dopalaniu spalin samochodowych budowane są z bloków składających się ze zwiniętej folii metalowej, na której jest osadzona warstwa aktywna katalitycznie. W celu otrzymania warstwy aluminy umożliwiającej osadzenie metalicznej fazy aktywnej prowadzono proces utleniania folii FeCrAl w zakresie temperatur 840-860°C. Zastosowano atmosferę mieszaniny argonu i tlenu, w której udział tlenu zmieniał się od 33% do 74%. Przeprowadzono badania struktury warstw tlenkowych, składu i właściwości katalitycznych.

EN

Catalytic sets which are currently using for the burning down of automotive exhaust are made with the rolled foil. Foil is usually deposited with active catalytic layer. In aim of depositing the metallic active phase on alumina layer, foil of FeCrAl was oxidized at the range of temperature 840-860°C. The atmosphere of argon and oxygen composition, which was used for oxidation, contained 33% -74% of oxygen. Structure, composition of oxide layers and their catalytic activity was tested.

10

Catalytic properties of hybrid alumina-Pt films produced on FeCrAl steel in a comparison test on 2-methylol-3butyn-2-ol conversion and oxidation of cyclohexane

Reszka K., Rakoczy J., Lisowski M.

Journal of KONES

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2007

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Vol. 14, No. 4

383-391

EN

The higher thermal resistance and the mechanical strength of the catalytic element carriers produced on metal substrates contribute to the further interest of the automotive industry on them despite that they show a smaller development of the surface compared to the ceramic carriers. The present work was focused on testing the catalytic properties of oxide films obtained as a result of the high-temperature oxidation of 0H18J5 steel foil under mixture of oxygen and argon which were coated with platinum by reactive dc magnetron sputtering. Hybrid coatings obtained by the oxidation of metal foil prior coated with aluminum nanofilms and then with platinum and the aluminum- platinum composites were also tested. The catalytic activity of the obtained coatings was tested by the pulse method in 2-methylol-3-butyn-2-ol decomposition reaction and the flow method in the process of cyclohexane oxidation. A catalytic test enabling the parameters of cyclohexane oxidation (temperature, time of reaction, cyclohexane concentration in zone of reaction) using the air to be controlled was developed for this flow method. The tests being carried out revealed an influence of different configuration of oxide films and platinum on their catalytic properties. Moreover, a high activity of alumina-Pt systems in the process of cyclohexane reheating with the air was confirmed.

11

Deposition of thin-film hybrid systems on fecral-steel substrate and testing their catalytic properties

Reszka K., Rakoczy J., Morgiel J.

Journal of KONES

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2005

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Vol. 12, No. 3-4

211-218

EN

Metal foils play more and more important part in production of catalytic converters for exhaust and industrial gas. The deposition of the active phase on the foil surface makes it possible to create the optimum conditions for the catalytic process and obtain the high-duty converters resistant to vibrations and thermal shock. The work was focused on the new thin-film technique designed for depositing the laminar and hybrid oxide systems obtained as a result of the high-temperature oxidation of the foil made of OH18J5 heat resisting steel, using a mixed oxygen-argon atmosphere with equal volume fractions, and then they were coated with Al2O3 nano-films by sputtering the alfa Al2O3 monolithic target with the aid of an r.f magnetron. Both the oxide layers without coating and the layers coated with Al2O3 nano-films were deposited with Pt coats by sputtering the metal target from a d.c magnetron. The thickness of each sputtered Al2O3 and Pt film did not exceed 25 nm. The catalytic activity of the obtained coatings and their acidic-basic properties within the range of b temperatures 523-673 K were determined on the basis of a 2-methylol-3-butyn-2-ol decomposition reactio

12

Zagadnienie brzegowe dla krzywoliniowego trójkata i njego zastosowanie w materiałach kompozytowych

Mityushev V., Reszka K.

Zeszyty Naukowe Politechniki Rzeszowskiej. Matematyka

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2001

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z. 25 [190]

131-138

EN

Let G+and G- be two uniconnected domains of a plane with a cammon boundary curve L. In a paper we determine a function u(x,y) harmonic in every domains G+ G-~ and satisfied some boundary condition on L. Some applications of such functions are also presented.