Wyniki wyszukiwania - BazTech

1

In situ-formed bacterial exopolysaccharide (EPS) as a potential carrier for anchorage-dependent cell cultures

Komorowski Piotr, Kołodziejczyk Agnieszka, Makowski Krzysztof, Kotarba Sylwia, Walkowiak Bogdan

Engineering of Biomaterials

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2021

|

Vol. 24, no. 159

18--23

EN

The study involved the use of a bacterial strain isolated from environmental samples which produce the biopolymer in the form of pellets in the submerged culture. This material (bacterial exopolysaccharide) is produced by bacteria of the Komogateibacter xylinus which are prevalent in the environment. The aim of this study was to characterize bacterial exopolysaccharides and commercial dextran-based “microcarriers” in terms of their roughness and cell culture effects, including the morphology and viability of the human hybridoma vascular endothelial cell line EA.hy926. The pellets were characterized using scanning electron microscopy (SEM) and atomic for¬ce microscopy (AFM). The resulting structures were used for cell culture of adherent cells (anchorage¬-dependent cells). At the same time, the cultures with commercial, dextran-based “microcarriers” were carried out for comparative purposes. After com¬pletion of the cell culture (24 hours of culture), the cellulose and commercial “carriers” were analyzed using SEM and AFM. Finally, the obtained cell dens¬ities (fluorescence labelling) and their morphological characteristics (SEM) were compared. The obtained results strongly support the applicability of bacterial exopolysaccharide (EPS) in tissue engineering to build innovative 3D scaffolds for cell culture, the more so that it is technologically possible to produce EPS as spatially complex structure

2

Differences in Roughness Parameter Values from Skid and Skidless Contact Stylus Profilometers

Grochalski Karol, Mendak Michał, Jakubowicz Michał, Gapiński Bartosz, Swojak Natalia, Wieczorowski Michał, Krawczyk Aleksandra

Advances in Science and Technology. Research Journal

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2021

|

Vol. 15, no 1

58--70

EN

Contact stylus profilometry is the leading surface texture measuring method in many manufacturing industries. For years it has been unmatched in terms of accuracy and reliability. Advancements in technology have led to the improvements in the profilometer design. A stylus can either have a built in skid or be skidless. In this study, the influence of skid on the measurement accuracy and repeatability was evaluated. Four different contact stylus profilometers were used to measure three standard roughness artifacts each. Every set of measurements consisted of 50 repetitions of the same profile, with the same parameters. Out of these profiles, five roughness parameters were calculated and were subjected to a statistical analysis. Relative errors of these parameters were also considered and presented individually for each roughness standard. Researchers found differences in the measurement results dispersion of various roughness parameters between the three roughness standards. The presented results of the measurements clearly indicated that there is a dispersion of the obtained values for the older type of contact stylus profilometer (P1, skid). The skidless portable devices, P2 and P3, have better measurement resolution, which results in a noticeably lower dispersion of measured values. A tabletop, stationary device utilizes a skidless measuring probe. It has both the best resolution and the highest rigidity, which results in the lowest dispersion of measured values. The lowest relative error of the Ra parameter was determined for the P2 device (9.2%) and the highest was determined for the P3 device (72.6%).

3

The study of linear correlation between surface roughness parameters and adhesion of flame sprayed coatings

Mikuliszyn J., Starosta R.

Journal of KONES

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2016

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Vol. 23, No. 1

223--229

EN

Adhesion is one of the reasons for limiting the use of thermally sprayed coatings. Many factors influence the adhesion of thermally sprayed coatings, for example: quality of the workmanship of surface preparation, method of thermal spraying, processing parameters, and the temperature of the preliminary preheat substrate, properties of the substrate and coating materials. Another one is the surface roughness. Attempts are made to use surface roughness parameters (e.g. Ra, Rz, Rq, Rku, Rsk) for prediction of adhesion of thermally sprayed coatings. However, most often these attempts end in failure. This article discusses the task of assessing the linear correlation between the twelve parameters of roughness or material ratio of various surface profiles and strength bond of coatings. For analysis, the following parameters were selected: Rz, Ra, Rq, Rsk, Rt, RSm, Rp, Rv, Rku, Rmr (50%), Rk, Rpk, Rvk. The steel substrates (S185) were machined by abrasive machining. The surface roughness of the steel substrate ranged Rz = 1.89-5.34 mm. Nickel-based coatings were applied by flame spraying by the Casto Dyn DS 8000 torch. Adhesion of coatings was measured by pull – off method. The flame sprayed coatings were characterized by adhesion to the steel substrate in the range of from 5.53 MPa to 8.28 MPa. The highest value of the correlation coefficient (Pearson – R)between parameters Rp, Rpk, and adhesion of thermally sprayed coatings were found. The coefficient R was equalto the 0.83, and the coefficient of determination R2 = 0.7. The lowest value of the correlation coefficient was found for the Rku roughness parameter amounting to 0.37. In the measurements carried out, it can be concluded that the prediction of adhesion of the coatings according to the roughness of the substrate, should be carried out by use the parameters characterizing the peaks height of roughness profile.

4

Badania topografii powierzchni przy uzyciu mikroskopii konfokalnej

Tartakowski Z., Dudzińska S.

Dozór Techniczny

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2016

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z. 5

22--26

PL

Istotnym czynnikiem wpływajacym na eksploatacje czesci maszyn jest stan ich warstwy wierzchniej uzyskany z procesów obróbczych i przetwórczych. W praktyce przemysłowej do badań stanu powierzchni powszechnie używane sa profilometry stykowe. Dla dokładniejszego opisu powierzchni coraz częściej stosowana jest technika pomiarowa 3D przy użyciu chromatycznej mikroskopii konfokalnej. W pracy przedstawiono praktyczne wykorzystanie mikroskopii konfokalnej do analizy warstwy wierzchniej gniazda formy wtryskowej.

EN

One of the most important factor affecting the exploitation of the machine parts is the surface layer condition after the processes of machining and processing. In industrial practice to study the state of the surface are commonly used Profilometers pin. More frequently for a more detailed characterization of surfaces is using 3D measurement by chromatic confocal microscopy. The paper presents practical using of confocal microscopy for analysis of the surface layer of the injection mold cavity.

5

Wyznaczanie korytarzy przewietrzających przy użyciu metody morfometrycznej dla wybranego fragmentu miasta Łodzi

Bochenek A., Klemm K.

Budownictwo i Architektura

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2016

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Vol. 15, nr 4

139--151

PL

W pracy podjęto próbę wyznaczenia terenów stanowiących potencjalne korytarze przewietrzające warunkujące prawidłowe funkcjonowanie systemu aeracyjnego miasta. Badanie zostało przeprowadzone przy użyciu jednej z najpopularniejszych metod – morfometrycznej, ze względu na niski koszt pozyskania danych oraz wysoką precyzję otrzymywanych wyników. Z uwagi na dominujący kierunek napływu wiatru, analizami objęto dowietrzny fragment miasta Łodzi. Pierwszy etap opracowania objął analizę podstawowych parametrów szorstkości terenu, tj. chropowatości podłoża (zo), przemieszczenia płaszczyzny zerowej (zd) oraz porowatości w obrębie warstwy dachowej (P). Na podstawie uzyskanych wyników oraz przyjętych kryteriów prawidłowego funkcjonowania korytarzy przewietrzających wyznaczono osiem obszarów swobodnego napływu powietrza do miasta.

EN

The aim of the paper was an indication of potential ventilation paths which affect proper functioning of the cities aerial system. The research was conducted using the most popular method – morphometric for the sake of low cost data gathering and high precision of final results. Due to the wind’s dominant direction, an analysis covered a windward part of Lodz. The first part of the research included an analysis of the basic roughness parameters such as: roughness length (zo), zero plane displacement height (zd) and porosity of the urban canopy layer (P). Based on the obtained results and taking into account ventilation paths criteria eight areas were designated which provide a free flow of air to the city.

6

Applicability of selected groups of roughness parameters for description of surface layer of flat-top “plateau” structures

Kowalski M., Wiśniewska M., Karolczak P., Stancekova D.

Advances in Science and Technology. Research Journal

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2016

|

Vol. 10, nr 32

32--39

EN

The aim of this study is to determine the usefulness of selected 2D roughness parameters for detecting changes of geometric features and the rate the quality of the surface generated in the process of honing combustion engines sleeves. The paper presents the importance of mathematical modeling of virtual surface topography with different participation of determined and random factor. The possibilities of modeling the flat-top “plateau” surface roughness characteristic for honed surface was showed. Suitability of application of the roughness parameter for description of the selected variable characteristics of roughness profiles were determined using the correlation coefficient and the additional evaluation index designated as t. Indicator t was used for comparing the percentage change of the tested value of modeled profile characteristics with changes selected for evaluation of the roughness parameters 2D.

7

The metrology of ground concrete surfaces morphology with 3D laser scanner

Sadowski L., Mathia T. G.

Management and Production Engineering Review

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2015

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Vol. 6, No. 2

40--44

EN

This paper is devoted to machining of concrete by grinding and the metrology of its surface morphologies. The surface morphology is still open problem from metrological as well as mathematical morphology points of views. In order to understand better abrasive process the raw morphologic state is compared with the ground concrete surfaces. The most significant results are presented in the form of profiles, 3D isometric views and isotropy analysis. Several 3D surface roughness parameters were calculated.

8

Surface quality assessment following high performance cutting of AZ91HP magnesium alloy

Gziut O., Kuczmaszewski J., Zagórski I.

Management and Production Engineering Review

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2015

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Vol. 6, No. 1

4--9

EN

The article presents test results of surface roughness after AZ91HP magnesium alloy machining with variable technological parameters (vc, fz, ap) as well as tool geometry (γ= 5◦ and γ = 30◦). Two carbide end mills were applied during the tests. Roughness analysis was conveyed at the end face (Ra, Rq, RzDIN, Rt, Ry, RSm) and lateral face (Ra, Rz, RSm) of the tested sample. A decrease of roughness parameters (for increasing vc) as well as an increase (with growing fz) was observed in the lateral face tests. Similar interrelations were noticed for end face of the sample. Lower roughness parameters values were recorded for tool rake angle equal to γ = 5◦.

9

Diagnostics of workpiece surface condition based on cutting tool vibrations during machining

Józwik J., Mika D.

Advances in Science and Technology. Research Journal

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2015

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Vol. 9, nr 26

57--65

EN

The paper presents functional relationships between surface geometry parameters, feedrate and vibrations level in the radial direction of the workpiece. Time characteristics of the acceleration of cutting tool vibration registered during C45 steel and stainless steel machining for separate axes (X, Y, Z) were presented as a function of feedrate f. During the tests surface geometric accuracy assessment was performed and 3D surface roughness parameters were determined. The Sz parameter was selected for the analysis, which was then collated with RMS vibration acceleration and feedrate f. The Sz parameter indirectly provides information on peak to valley height and is characterised by high generalising potential i.e. it is highly correlated to other surface and volume parameters of surface roughness. Test results presented in this paper may constitute a valuable source of information considering the influence of vibrations on geometric accuracy of elements for engineers designing technological processes.

10

Rola strategii pomiarów topografii powierzchni w ocenie wybranych parametrów chropowatości

Kamieńska-Krzowska B., Kłonica M.

Mechanik

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2014

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R. 87, nr 8-9CD1

138-145

PL

Intensywny rozwój różnych technik pomiaru topografii powierzchni pozwala na przewidywanie właściwości funkcjonalnych powierzchni oraz ocenę jej jakości. Na wyniki oceny parametrów chropowatości duży wpływ ma strategia ich pomiaru. W pracy przedstawiono wyniki badań dotyczących pomiarów wybranych parametrów chropowatości 2D i 3D. Badano wpływ trzech różnych filtrów oraz dwu wartości odcinka elementarnego (cut-off) na cztery parametry chropowatości Rt, Ra, Rmr, Rsm oraz ich odpowiedniki 3D. Pomiary wykonano na wzorcach chropowatości po obróbce toczeniem i szlifowaniem.

EN

An intensive development of various surface topography measuring surface techniques allows the prediction of the functional attributes of the surface and also evaluation of its quality. The results of the evaluation of surface roughness is highly influenced by their measurement strategy. The article presents some results of studies the selected roughness parameters measurement 2D and 3D. The was examined the effect of three different filters and two values cut-off to four roughness parameters Rt, Ra, Rmr , Rsm and their 3D counterparts. Measurements were conducted on roughness patterns after turning and grinding processes.

11

Evaluation of micro-geometry changes on surfaces after chemical pretreatment

Draganovská D., Tomáš M., Ižol P

Archives of Mechanical Technology and Automation

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2014

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Vol. 34, no. 2

17--24

EN

The paper discusses the evaluation of the surface quality in terms of microgeometry. For the experiment, samples of S235JRG2 steel were used. The surface of the steel was chemically pretreated prior to the tests. Thefocus of the research was on the surfaces of steel sheets in states such as an initial state surface, degreased surface, galvanized surface, a surface after galvanizing and chromatizing, degreased and phosphated, and a surface pretreated with degreasing and phosphating with RAL coating. The measurement of microgeometry parameters on the samples was evaluated by a profilometric device Surftest SJ – 201, Mitutoyo, Japan. The roughness parameters Ra, Rz, RSm, and RPc, were measured on evaluated surfaces and compared. Profilographs, as well as Abbot Fireston curves were also evaluated.

PL

W artykule oceniono jakość powierzchni z punktu widzenia mikrogeometrii. W badaniach wykorzystano próbki ze stali S235JRG2. Powierzchnie badanych próbek poddano różnym zabiegom obróbki chemicznej. W badaniach przeanalizowano próbki w stanie początkowym oraz po procesach: odtłuszczania, galwanizacji, galwanizacji i chromowania, odtłuszczania i galwanizacj odtłuszczania i galwanizacji z powłoką RAL. Parametry mikrogeometrii powierzchni zmierzono za pomocą stykowego profilografometru Surftest SJ-201 Mitutoyo. Na podstawie pomiarów wyznaczono parametry chropowatości powierzchni Ra, Rz, RSm i RPc badanych próbek, a następni dokonano ich porównania. Analizie poddano również profilogramy i krzywe Abbotta-Firestone’a.

12

Biodegradacja poli(estrouretanów) w symulowanych warunkach kompostowania

Pilch-Pitera B., Wojturska J.

Polimery

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2012

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T. 57, nr 11-12

852-860

PL

Poliuretany syntezowane w dwuetapowym procesie poliaddycji diizocyjanianu trimetyloheksametylenu (TMDI), poli(e-kaprolaktono)diolu o różnym ciężarze cząsteczkowym (PCL 750, PCL 1250) i glicerolu (GLI), poddano biodegradacji w symulowanych warunkach kompostowania z wykorzystaniem wermikulitu jako inertnego medium stałego. Proces biodegradacji realizowano w ciągu 42—106 dni. Stopień biodegradacji określano na podstawie wyznaczonego ubytku masy próbek, zmian parametrów chropowatości i zmian składowych swobodnej energii powierzchniowej (SEP). Określano również właściwości mechaniczne próbek przed i po degradacji. Za pomocą mikroskopii optycznej i konfokalnej udokumentowano zmiany wyglądu powierzchni próbek po okresie kompostowania w symulowanych warunkach. Stwierdzono, że już po 6 tygodniach biodegradacji następuje znaczna deterioracja próbek.

EN

Polyurethanes synthesized in a two-step polyaddition process of trimethylhexamethylene diisocyanate (TMDI), poly(e-caprolactone) diols with different molecular weights (PCL 750, PCL 1250) and glycerol (GLI) were biodegraded under simulated composting conditions with the use of vermiculite as an inert solid medium. Biodegradation process was carried out over a period of 42—106 days. The degree of biodegradation was determined on the basis of weight loss of the samples as well as the changes in the roughness parameters and surface free energy components (SEP). The mechanical properties of the samples before and after degradation were also determined. Additionally, changes in the surface appearance of the samples after composting at simulated conditions were documented using both optical and confocal microscopy. It was found that even after six weeks of biodegradation a significant deterioration of the samples took place.

13

Tribological aspects of some materials abrasive-water jet cutting

Holka H., Matuszewski M., Musiał J., Styp-Rekowski M.

Journal of Machine Engineering

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2012

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Vol. 12, No. 2

46--52

EN

This article presents results of comparative studies into the roughness (very significant tribological factor) of surfaces cut using the AWJM method. Cutting was performed on samples made of quenched and tampered alloy steel (1.2080), plastic (polyamide PA6) and mineral material (syenite). Variable parameters in the cutting process included: jet pressure and feed. As a result of measurements involving selected roughness parameters (Ra, Rz and Rq), it was discovered that the majority of variable factors had a significant effect on the cut surface roughness. It was also demonstrated that the contact method measurements cannot be performed with regard to plastics because the results are characterised by a very great scatter of results values, making them unreliable.

14

Thickness evaluation of the carbon coatings manufactured on magnesium alloys using optical profiler

Gołąbczak M., Jacquet P.

Journal of Machine Engineering

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2012

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Vol. 12, No. 2

29--36

EN

One of the problems in identification of carbon nanocoatings is measurement of their thickness. There are a lot of methods which allow for determination of thickness i.e. SEM analysis of cross section of sample with manufactured coating, nanoindentation analysis with using DSP (Digital Signal Processing) method, roughness analysis with using different kind of profilers. In this paper the technology of manufacturing of carbon coatings on AZ31 magnesium light alloy has been depicted and optical profiler has been used for thickness evaluation of these coating. Obtained results allowed for precise estimation of manufactured carbon coatings thickness. In this way it was also possible to compare obtained thickness results with thickness evaluated by other methods.

15

Metodyka oceny zdolności klasyfikacyjnej parametrów charakteryzujących cechy stereometryczne nierówności powierzchni

Kacalak W., Szafraniec F., Tomkowski R., Lipiński D., Łukianowicz C.

Pomiary Automatyka Kontrola

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2011

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R. 57, nr 5

542-546

PL

W pracy opracowano metodykę wyboru parametrów do kompleksowej oceny cech stereometrycznych powierzchni. Przeprowadzono analizy zdolności klasyfikacyjnej parametrów. Wykazano, że wybierając parametry do klasyfikacji zbioru należy uwzględnić: zdolność klasyfikacyjną, przydatność technologiczną oraz łatwość interpretacji, pomimo zdolności klasyfikacyjnej wielu parametrów. Przedstawiono nowe parametry i metody klasyfikacji parametrów na podstawie cech stereometrycznych.

EN

The increase in requirements for accuracy and properties of elements, minimisation of the wear of materials, mass and dimensions of elements, the increase in load capacity and endurance, and also the development of manufacturing technology, lead to the development of many measurement methods and equipment to carry them out as well as to increase the number of parameters for use in evaluation of the surface stereometry features. Taking into account new requirements, a new system for evaluation of the surface stereometry features was developed. The system consists of a collectionof evaluation methods and applications to complex analysis and surface evaluation. In this paper a methodology for selecting parameters for complex evaluation of the surface topography features is presented. Analysis of the classification ability of parameters was performed. It was proved that when selecting parameters for the classification of a collection one should consider: classification ability, technological usability and ease of interpretation in spite of classification ability of many parameters. New parameters and methods for classification of parameters on the basis of the stereometry features are presented.

16

Selected problems of effectiveness of processing of magnesium alloys with a Kordell design tool

Zagórski I., Kuczmaszewski J.

Management and Production Engineering Review

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2011

|

Vol. 2, No. 4

90-96

EN

The paper presents an application of milling, applications and examples of aircraft elements made from Mg alloys, processing conditions for machining Mg alloys, main trends in increasing the effectiveness of production in the aircraft industry, the programme and methodology of the conducted research, research results and their analysis, conclusions following from the study, and literature data.

17

Pomiar a ocena struktury geometrycznej powierzchni wirtualnej dla przypadku frezowania walcowo-czołowego

Cieloszyk J.

Zeszyty Naukowe Politechniki Poznańskiej. Budowa Maszyn i Zarządzanie Produkcją

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2010

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Nr 13

5-10

PL

W artykule przedstawiono wybrane problemy występujące na styku modelowania a pomiaru i oceny struktury geometrycznej powierzchni (SGP). Przedstawiono wyniki badań doświadczalnych i analitycznych powierzchni frezowanych. Porównano powierzchnie rzeczywiste i wirtualne dla przyjętego modelu. Ocenie poddano profile pierwotne, falistości i chropowatości powierzchni rzeczywistych i wirtualnych.

EN

In this paper, the idea of estimated virtual milling surface is presented. The comparative analysis of chosen profiles: P, W, R, parameters; roughness waviness for real and virtual machining surfaces are shown. The results of the investigations of real and virtual machining surfaces indicated that the idea of estimated will be usefully method. Simultaneously, it is important that real and virtual estimated have to take place in this some measuring conditions. "Measuring" virtual surface give possibility widely estimated surface roughness on each stage of engineering works.

18

Właściwości powierzchniowych warstw kompozytów Ni/PTFE

Trzaska M., Kucharska B.

Kompozyty

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2009

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R. 9, nr 4

363-368

PL

Przedstawiono wyniki badań wpływu parametrów procesu na strukturę i właściwości powierzchniowe warstw kompozytowych Ni-PTFE wytwarzanych metodą redukcji elektrochemicznej na podłożu stalowym. W celach porównawczych badano również warstwy niklowe wytwarzane elektrochemicznie w procesach o takich samych parametrach jak warstwy Ni/PTFE. Warstwy osadzano w kąpieli Wattsa o małym stężeniu, modyfikowanej dodatkami substancji organicznych. Proces realizowano przy różnej zawartości dyspersji teflonowej w kąpieli. Wykonano analizę strukturalną wytworzonych warstw i wyznaczono wielkości krystalitów metodą aproksymacji opartej na analizie profilu linii dyfrakcyjnych. Przedstawiono morfologię i topografię wytworzonych warstw. Wyznaczono profile geometryczne powierzchni oraz określono parametry chropowatości. Zbadano mikrostrukturę materiału kompozytowego warstw Ni/PTFE za pomocą transmisyjnego mikroskopu elektronowego (TEM). Metodą Vickersa określono mikrotwardość warstw Ni/PTFE oraz Ni. Wykonano pomiary statycznego kąta zwilżania (SCA). Za pomocą scratch testu oceniono adhezję warstw niklowych oraz kompozytowych Ni/PTFE w zależności od zawartości teflonu oraz dodatków substancji organicznych w kąpieli. Stwierdzono, że wraz ze wzrostem zawartości PTFE oraz dodatków organicznych w kąpieli adhezja warstw kompozytowych do stalowego podłoża zmniejsza się oraz pojawiają się charakterystyczne pęknięcia.

EN

The aim of the present research was to investigate the influence of process parameters on the structure and surface properties of nickel layers and composite layers Ni-PTFE deposited on the steel substrate (St3S) by the electrochemical reduction method. Electrochemical nickel coatings were also investigated to have a comparison with composite layers. The coatings were deposited from a small concentration of Watts bath modified by the organic additives- saccharine and sodium dodecyl sulfate. Polytetrafluoroethylen was used as a water disperse with nonionic surfactant of particle dimensions in the range of 0.1-0.3 žm. The electrodeposition process was performed with constant current density (3 A/dm2) at different contents of PTFE disperse phase in the bath (5-20 g/dm3). Structural analysis of produced layers was also performed. On that base the size of crystallites was calculated. The topography and morphology of produced layers are presented. Geometric profiles and roughness parameters were determined. That was observed that smoothing of the nanocrystaline nickel surface increases in comparison with surface of microcrystaline nickel layers. The microstructures of the coatings were examined by transmission electron microscope (TEM). The microhardness of the materials has been investigated by using the Vicker's method. It was observed that the hardness exhibit the layers deposited in the bath with saccharine and sodium dodecyl sulfate additives. Measurements of static contact angle (SCA) were applied in the investigations of surface properties of composite electrochemical Ni/PTFE coatings. The results of the investigations seem to be helpful in characterizing hydrophobic and antiadhesive properties of the produced coatings. Layers adhesion was evaluated by the scratch test. The morphologies of nickel and composite layers after scratch tests and diagram of acustic emision are presented. It was found that micro- and nanocrystaline nickel layers reveal perfect adhesion to the steel substrate. Increase of PTFE disperse phase in Watts bath causes deterioration of adhesive properties. Regarding the coating types it can be seen different locations of damages and loads being typical for such tests.

19

Wybrane właściwości geometrycznej struktury powierzchni wytworów porowatych otrzymanych z polietylenu

Garbacz T., Samujło B.

Polimery

|

2008

|

T. 53, nr 6

471-476

PL

Ustalono warunki, w których metodą wytłaczania porującego uzyskano porowate powłoki zewnętrzne kabli energetycznych i instalacyjnych odpowiadające wymogom eksploatacyjnym (kabel o oznaczeniu handlowym "OWY 3 x 1,5mm2 450/750 V"). Powłoki wytwarzano z dwóch handlowych polietylenów PE-HD firmy Borealis. Polietylen mieszano ze środkiem porującym "Hydrocel 530" w ilości do 1 % mas. Oceniono wpływ zawartości środka porującego na średnią gęstość, stopień sporowacenia oraz na parametry chropowatości powierzchni: średnie arytmetyczne odchylenie profilu chropowatości (Ra), wysokość chropowatości według 10 punktów (Rz), maksymalną wysokość chropowatości (Rm) oraz średni odstęp chropowatości (Sm). Zależności Ra i Rz w funkcji udziału środka porującego opisano równaniami regresji. Uzyskano przy tym wartości współczynników korelacji (rkw>0,985) świadczące o dobrej zgodności wybranego modelu matematycznego z danymi doświadczalnymi.

EN

The conditions were found in which the cellular topcoats of energetic and installation cables, fulfilling exploitation requirements (as for cables of trademark "OWY 3 x 1.5mm2 450/750 V"), were obtained by foam extrusion (Fig. 1, 2, 4 and 5). The topcoats were made of two commercial grades of PE-HD polyethylene, produced by Borealis (Table 1). Polyethylene was mixed with blowing agent "Hydrocel 530" in amounts up to 1 wt. %. The effects of blowing agent content on mean density, porosity degree (Table 2) and the roughness parameters of the surface were evaluated. Roughness parameters studied were as follows: mean arithmetic deviation of surface roughness profile (Ra), ten-point height of irregularities (Rz), maximum peak to valley height (Rm) and mean spacing of irregularities (Sm) (Table 3 and 4). Dependence of (Ra) and (Rz) on blowing agent content has been described with regression equations (Table 5). The values of correlation factors obtained (rkw>0.985) confirmed the good agreement of selected mathematical model with experimental data.