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1

The effectiveness of impregnation of building materials of cellulose origin and its impact on selected properties

Niewiadomski Paweł, Karolak Anna, Oleksiak Marta, Chowaniec-Michalak Agnieszka

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 2

art. no. e148876

EN

One of the biggest challenges facing a designer of paper structures is its low resistance to moisture and water. Paper is a hydrophilic material that absorbs moisture from the outside. This causes the hydrogen bonds between the cellulose molecules to loosen and as a result a rapid decrease in strength parameters. In order to be able to use paper as a construction material, there is a need to select and evaluate the effectiveness of the appropriate impregnant, as well as to know its impact on the mechanical properties of the impregnated paper. The paper analyzes the effect of the use of various impregnations, including wood oil, yacht lacquer, and fire-retardant agent impregnation, on the tensile strength of several types of cellulose-derived materials, e.g. corrugated board, solid board, paper cores, and honeycomb board. The effectiveness of the impregnation was also assessed using the method of measuring the contact angle of the reference and impregnated surfaces.

2

Application of Drop Shape Analyzer to measure the wettability of cotton woven fabrics

Kamińska Dominika, Matusiak Małgorzata, Čorak Ivana, Tarbuk Anita

Technologia i Jakość Wyrobów

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2023

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R. 68

80--92

EN

The method of measuring the contact angle, applied in an assessment of material hydrophobicity, is well known and suitable for evaluating the solid substrates with smooth geometry. For these substrates data evaluation is quite straightforward. In the case of textile substrates, the interpretation of the contact angle value is difficult, mainly due to two properties of the substrate - the roughness and an ability of the substrate to absorb the liquid drops. In the presented work 6 cotton fabrics with different weaves (plain, twill 3/1 S, twill 2/2 S, rep 2/2 (2), rep 1/1 (0,1,0), hopsack 2/2 (0,2,0)) were tested. Measurements were performed using the Drop Shape Analyzer (DSA).

PL

Metoda pomiaru kąta zwilżania, stosowana w ocenie hydrofobowości materiałów, jest dobrze znana i nadaje się do oceny podłoży stałych o gładkiej geometrii. Dla tych podłoży ocena danych jest stosunkowo prosta. W przypadku materiałów włókienniczych interpretacja wartości kąta zwilżania jest utrudniona, głównie ze względu na dwie właściwości podłoża – chropowatość oraz zdolność podłoża do zasysania kropli cieczy. W ramach niniejszej pracy badaniom poddano 6 tkanin bawełnianych o różnych splotach (płócienny, skośny 3/1 S, skośny 2/2 S, ryps podłużny 2/2 (2), ryps poprzeczny 1/1 (0,1,0) oraz panama 2/2 (0,2,0)). Pomiary zostały przeprowadzone przy użyciu przyrządu Drop Shape Analyzer (DSA).

3

Analysis of the effect of assembly joints technology on the strength of adhesive joints of poly(methyl methacrylate) (pmma) used in advertising elements

Rudawska Anna, Penkała Piotr, Miszczuk Bartosz, Stančeková Dana

Technologia i Automatyzacja Montażu

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2023

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nr 2

3--10

EN

The aim of the article was to present issues related to the influence of the assembly joints technology (the type of adhesive material and the adhesive application) on the strength of the adhesive joints of poly(methyl methacrylate) (PMMA) used in the production of advertising elements. Angular adhesive joints, which are one of the types of joints made in the construction of advertising elements, were used in the study. The bonded material was poly(methyl methacrylate) (PMMA) of 8 mm thick. Two types of adhesives were used to make the adhesive joints: one-component solvent-based adhesives and methylene chloride as a solvent. Experimental tests determined the wettability of the surface of the adherends (with and without a protective coating) and the work of adhesion based on the measurement of the contact angle, as well as the strength of adhesive joints in accordance with the ISO 4578 standard. Based on the results of strength tests, it can be seen that the use of a solvent allows for obtaining equally strong joints as with the use of solvent-based adhesives. The purposefulness of using coatings protecting not only against dirt or mechanical damage in the form of scratches was also confirmed, but also the possibility of increasing (security) adhesive properties, defined in this case by wettability.

PL

Celem artykułu było przedstawienie zagadnień związanych z wpływem technologii połączeń montażowych (rodzaju materiału klejącego i sposobu aplikacji kleju) na wytrzymałość połączeń klejowych z poli(metakrylanu metylu) (PMMA) stosowanych w produkcji elementów reklamowych. W badaniach wykorzystano połączenia klejowe kątowe, które są jednym z rodzajów połączeń wykonywanych w konstrukcji elementów reklamowych. Łączonym materiałem był poli(metakrylan metylu) (PMMA) o grubości 8 mm. Do wykonania połączeń klejowych zastosowano dwa rodzaje jednoskładnikowych klejów rozpuszczalnikowych oraz chlorek metylenu, jako rozpuszczalnik. W badaniach doświadczalnych określono zwilżalność powierzchni klejonych elementów (z powłoką ochronną i bez) oraz pracę adhezyjną na podstawie pomiaru kąta zwilżania, a także wytrzymałość połączeń klejowych zgodnie z normą ISO 4578. Na podstawie wyników badań wytrzymałościowych można stwierdzić, że zastosowanie rozpuszczalnika pozwala na uzyskanie połączeń równie wytrzymałych, jak przy zastosowaniu klejów rozpuszczalnikowych. Potwierdzono również celowość stosowania powłok zabezpieczających nie tylko przed zabrudzeniami czy uszkodzeniami mechanicznymi w postaci zarysowań, ale także w celu zwiększenia (zabezpieczenia) właściwości adhezyjnych, określanych w tym przypadku przez zwilżalność.

4

Farba fosforescencyjna w laminatach szklanych

Reich Stefan, Ives Shawn, Pfütze Christian

Świat Szkła

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2023

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R. 28, nr 3

37, 38--41

5

Wpływ działania plazmy niskotemperaturowej na zmiany zwilżalności wybranych polimerów

Hołysz Lucyna, Kamela (Rymuszka) Diana, Terpiłowski Konrad, Chibowski Emil

Wiadomości Chemiczne

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2021

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[Z] 75, 9-10

1270--1295

EN

The effects of air, oxygen and argon plasma treatment on wetting and energetic properties of polymers: polymethylmethacrylate (PMMA), polyetheretherketone (PEEK), polyoxymethylene (POM), polyamide (PA6G), polycarbonate (PC) and polypropylene (PP) were studied. The changes in surface properties of PMMA, PEEK, POM, PA6G polymers after the air plasma treatment, and PP and PC polymers after the Ar or O2 plasma treatment were determined via the measurement of advancing and receding contact angles of three liquids having different polarity, i.e. water, formamide and diiodomethane. Having the determined contact angles the surface free energy and its components of the polymers were calculated using three different theoretical approaches, namely: acid-base Lifsthitz-van der Waals (LWAB), contact angle hysteresis (CAH) and Owens and Wendt (O-W). The effects of plasma treatment were further determined by calculations of the adhesion work and work of spreading of water on modified polymer and compared to values calculated for the unmodified surfaces. Then for the PEEK and POM modified with the air plasma, their surface wettability was determined after 14 days from the exposure to the plasma. It was found that plasma treatment caused better wettability what reflected in a decreased contact angles measured on the modified polymer surfaces. The greatest changes appeared for polar liquids, i.e. water and formamide. It pointed to an increased the surface hydrophilicity after the plasma treatment. The changes correlated also with the increased polar interactions due to appearance polar groups on the surface. For the studied polymer surfaces, generally the dispersive interactions practically did not change, regardless the treatment time and plasma type. The total surface free energy values calculated for the polymers from three different approaches to interfacial interactions are similar. However, the energy values are apparent because they depend s upon the kind of liquid used for the contact angles measurement. Irrespectively of the plasma type, for all polymers an increase of the adhesion work of water in reference to the unmodified surfaces was observed. The most appropriate time to improve the adhesion between the polymer surface and liquid was found to be 25 or 60 s. However, the effects of plasma treatment are not permanent. With the storage time the contact angles have increased. This can be due to the structure reorganization within a few nm thick the surface layer.

6

Characteristic of polypropylene nanocomposite material reinforcement with hydroxyapatite for bone replacement

Obaid M. N., Sabr O. H., Hussein A. A.

Journal of Achievements in Materials and Manufacturing Engineering

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2021

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Vol. 104, nr 1

21--30

EN

Purpose: Human bone suffered some degeneration due to age and accidents; therefore, there are many interests in the prepared synthetic bone with properties nearer to natural bone. The present study prepared a nanocomposite of polypropylene reinforced with different weight fraction of Nano hydroxyapatite (HAp) to be used as a bone replacement with good biological properties that enhanced the growth of osteoplastic cells and enhance the prevention of clots and coagulates creation. Design/methodology/approach: Nanocomposite from polypropylene reinforced with different weight fraction of Hydroxyapatite (HAp) (1,2 and 3) % prepared by first dispersion Nano hydroxyapatite insolvent and then mixing with a pellet of polypropylene by the twin-screw extrusion process, the current research study the surface properties ( atomic force microscopy (AFM), contact angle test) Moreover, it studied the characteristics of prepared nanocomposite materials (Differential Scanning Calorimetry (DSC), Field Emission-Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared (FTIR)). Findings: The AFM results show the surface roughness decreased with increasing content of HAp, which diminished the chance of creation clots and coagulates on it. The contact angle results referred to polypropylene behaviour transformed from hydrophobic to hydrophilic with addition HAp that permission to grow the osteoplastic cell on it, so the healing process is accelerated. Moreover, the FE-SEM images revealed uniform distribution and good bonding between polypropylene and Hydroxyapatite. The thermal properties were measured by the DSC test showed the melting temperature, and the enthalpy of melting (indicated to increase the crystalline structure per cent) are increased with increasing the percentage of Hydroxyapatite. Research limitations/implications: This research studied the characteristics of nanocomposite materials prepared by three steps (dispersion by ultrasonic device, manually mixed and melting and mixing by twin extruder) which can be used as a bone replacement. However, the main limitation was the uniform distribution of nano-hydroxyapatite within the matrix. In a further study, the cytotoxic test can be tested to study the effect of prepared nanocomposite on living cells’ growth. Practical implications: The interest object is how to connect among different properties to prepared bone replacement with good properties and biocompatibility that made able to stimulate the growth and healing process. Originality/value: The nano-hydroxyapatite is a biomaterial that has a composition similar to the natural mineral phase of the bone and does not have any negative effect, which enhanced the growth of osteoplastic cells and decreased the clots and coagulates creation; therefore, nano-hydroxyapatite is used to decrease the surface roughness which decreased the chance of coagulation creation and to enhance the hydrophilic properties.

7

Comparative analysis of wetting ability of aluminum sheets with different surface roughness parameters by epoxy adhesive

Domińczuk Jacek, Krawczuk Anna

Technologia i Automatyzacja Montażu

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2020

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nr 2

34--40

EN

The article presents the analysis of the wetting ability by Epidian 5 epoxy resin with hardener Z1 of EN AW-2017A aluminum alloy sheets. The material sheets were subjected to the selected methods of processing in order to obtain different parameters of the geometric development of the surface. The energy state of the surface layer was examined on the prepared surfaces, taking the polar and non-polar free surface energy components into account. On the basis of the obtained results, wetting envelopes were determined, which represent the limit value of the surface energy components of the wetting liquid, ensuring good wetting. As part of the research, an analysis of the possibilities of achieving maximum adhesion work between a solid and a liquid in the event of changes in the contact angle was also conducted. This analysis allows one to determine how the parameters of the test adhesive deviate from the ideal, i.e. those for which the surface tension at the interface reaches the minimum value. Based on the results of the analysis, a summary was prepared, showing the ability of the adhesive to wet surfaces with different roughness parameters.

PL

W artykule przedstawiono analizę zdolności zwilżania przez klej Epidian 5 z utwardzaczem Z1 powierzchni blach ze stopu aluminium EN AW-2017A. Blachy poddano wybranym sposobom obróbki w celu uzyskania odmiennych parametrów rozwinięcia geometrycznego powierzchni. Na tak przygotowanych powierzchniach przeprowadzono badania stanu energetycznego warstwy wierzchniej z uwzględnieniem składowej polarnej i niepolarnej swobodnej energii powierzchniowej. Na podstawie otrzymanych wyników wyznaczono krzywe zwilżania, które przedstawiają graniczną wartość składowych swobodnej energii powierzchniowej cieczy zwilżającej, zapewniające uzyskanie dobrego zwilżania. W ramach badań przeprowadzono również analizę możliwości osiągnięcia maksymalnej pracy adhezji między ciałem stałym, a cieczą w przypadku zmian kąta zwilżania. Analiza ta pozwoliła na określenie na ile parametry badanego kleju odbiegają od idealnych, czyli takich, dla których napięcie powierzchniowe na granicy faz osiąga wartość minimalną. W oparciu o uzyskane wyniki analiz dokonano zestawienia obrazującego zdolność kleju do zwilżania powierzchni o różnych parametrach chropowatości.

8

Enhancement of tribological properties and characteristic of polymer matrix composite (UHMWPE reinforced with short fibres of polyester) for Total Disc Replacement (TDR)

Obaid M. N., Radhi S. H.

Journal of Achievements in Materials and Manufacturing Engineering

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2020

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Vol. 102, nr 2

55--65

EN

Purpose: The number of people suffering from Degenerative Disc Disease (DDD) is increasing. The disease causes heavy pain and restrict a number of day-to-day life activities. In extreme cases, the degraded disc is removed under total disc replacement which is usually made up of Ultra-High Molecular Weight Polyethylene (UHMWPE). The material has astounding biocompatible characteristics mechanical properties and wear resistance. However, these characteristics are insufficient in arthroplasty application. Therefore, research investigations are ongoing to improve tribological properties through reinforcement that may result in a composite material of UHMWPE. Thus the current study is aimed at reinforcing UHMWPE with short fibres of polyesters to enhance the tribological properties and surface characteristic so as to improve wear resistance and nourish the fibroblast cells on synthetic disc. Design/methodology/approach: The researcher prepared UHMWPE composite material, reinforced with different weight fractions of short polyester fibres (2, 4, 6, 8 and 10% following hot press method. Further pin-on-disc device was used to study the tribological properties (coefficient of friction and volume of wear). The study tested surface roughness and surface characteristics by atomic force microscopy (AFM) device, hardness by shore D device, contact angle to study the effect of polyester short fibres on wettability of UHMWPE surface and tested the thermal properties and crystalline degree using Differential Scanning Calorimetry measurement (DSC) device. Findings: The results infer that the wear resistance got improved when using 2% w.t polyester though it got decreased initially. However, the value was still more than neat UHMWPE. There was a decrease observed in coefficient of friction, but after 4 w.t% polyester, the coefficient of friction got increased due to increasing percentage of fibres which make it harder and stiff compared to UHMWPE. There was a decline observed in surface roughness due to alignment of the fibres with smooth surface. The contact angle got increased in a moderate range while the roughness enhanced the growth of fibroblast cell. The hardness of composite material got increased, because the fibres turned stiffer and harder than the matrix. DSC results infer the improvements in thermal stability due to high thermal properties of polyester fibres compared to UHMWPE. The degree of crystallinity got increased which in turn enhanced wear resistance, especially at 6 w.t % polyester fibres. There was a mild increase observed in density since the density of polyester is higher than polymer. Research limitations/implications: The major challenge was the dispersion of fibres. Uniform distribution of fibres within the matrix (UHMWPE) was achieved through two steps of mixing processes such as mechanical mixture and twin extruder. In future studies, fatigue tests must be conducted to study the behaviour of prepared composite materials under fatigue cycle. Practical implications: A significant objective is how to connect among different properties to obtain good improvement in tribological and surface properties so as to enhance wear resistance and growth of fibrolase cells. Originality/value: In this study, polymeric short fibres were used as reinforcement with polymeric matrix to enhance the wettability of fibres with matrix. In this way, the bonding among them got increased which supports the tribological, surface, and crystalline behaviour.

9

Evaluation of the contact angle and wettability of hydrophobised lightweight concrete with sawdust

Szafraniec Małgorzata, Barnat-Hunek Danuta

Budownictwo i Architektura

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2020

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Vol. 19, no 2

19--32

EN

The aim of the research presented in the paper was to evaluate the feasibility of using hydrophobic preparations based on organosilicon compounds for protection treatment on the lightweight concrete modified with sawdust. The experimental part of the work concerns the physical and mechanical properties of lightweight concrete and the influence of two hydrophobic agents on the contact angle of the material. Lightweight concrete contact angle (θw) was determined as a time function using one measuring liquid. Water repellent coatings in lightweight concrete structure with the coarse aggregate sawdust (CASD) using electron microscopy were presented. The effectiveness of hydrophobisation of porous lightweight concretes was determined on the basis of the research. For the hydrophobic surface, the contact angle decreased and it depended on the used agents. The lowest contact angle of 40.2° (t=0) was obtained for reference concrete before hydrophobisation and 112.2° after hydrophobisation with a methyl-silicone resin based on organic solvent. The results of scientific research confirm the possibility to produce lightweight concretes modified with CASD with adequate surface protection against external moisture.

PL

Celem badań przedstawionych w pracy była ocena możliwości zastosowania preparatów hydrofobowych na bazie związków krzemoorganicznych do zabezpieczania betonu lekkiego modyfikowanego trocinami. Część doświadczalna pracy dotyczy właściwości fizycznych i mechanicznych betonu lekkiego oraz wpływu dwóch preparatów hydrofobowych na kąt zwilżania materiału. Określono kąt zwilżania betonu lekkiego (θw) w funkcji czasu za pomocą jednej cieczy pomiarowej. Za pomocą mikroskopu elektronowego pokazano powłoki hydrofobowe w strukturze betonu lekkiego, w którym zastosowano trociny jako kruszywo grube (CASD). Na podstawie badań określono skuteczność hydrofobizacji porowatych betonów lekkich. Dla powierzchni hydrofobowej zmniejszył się kąt zwilżania i był on zależny od zastosowanych środków. Najniższy kąt zwilżania 40,2° (t=0) uzyskano dla betonu wzorcowego przed hydrofobizacją i 112,2° po hydrofobizacji żywicą metylo-silikonową na bazie rozpuszczalnika organicznego. Wyniki badań naukowych potwierdzają możliwość otrzymywania betonów lekkich modyfikowanych za pomocą CASD z odpowiednią ochroną powierzchni przed działaniem wilgoci z zewnątrz.

10

Failure characteristics and strength model of composite rock samples in contact zone under compression

Wang Qihu, Wang Jie, Ye Yicheng, Jiang Wei, Yao Nan

Archives of Mining Sciences

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2020

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Vol. 65, no. 2

347--361

EN

Significant differences in the physical and mechanical properties exist between the rock masses on two sides of an ore-rock contact zone, which the production tunnels of an underground mine must pass through. Compared with a single rock mass, the mechanical behavior of the contact zone composite rock comprising two types of rock is more complex. In order to predict the overall strength of the composite rock with different contact angles, iron ore-marble composite rock sample uniaxial compression tests were conducted. The results showed that composite rock samples with different contact angles failed in two different modes under compression. The strengths of the composite rock samples were lower than those of both the pure iron ore samples and pure marble samples, and were also related to the contact angle. According to the stress-strain relationship of the contact surface in the composite rock sample, there were constraint stresses on the contact surface between the two types of rock medium in the composite rock samples. This stress state could reveal the effect of the constraint stress in the composite rock samples with different contact angles on their strengths. Based on the Mohr-Coulomb criterion, a strength model of the composite rock considering the constraint stress on the contact surface was constructed, which could provide a theoretical basis for stability researches and designs of contact zone tunnels.

11

The Tribological Properties of the TI6AL4V Alloy with Nitrogen Ion Implantation

Piotrowska Katarzyna, Baranowicz Paweł, Wysokińska-Miszczuk Joanna, Madej Monika, Skóra Monika

Tribologia

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2019

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nr 1

37--47

EN

The article presents the analysis of the influence of ion implantation on the properties of titanium alloy used in biotribological systems. The object of the study was the titanium alloy Ti6Al4V implanted with nitrogen ions. Tribological model tests were carried out in combination with a sphere with Al2O3 – a Ti6Al4V alloy disc implanted with N+ ions. Experimental friction tests were carried out on pin-on-disc testers in conditions of technically dry conditions and in conditions of lubrication with the Ringer’s solution. The tests on the TRB tester were carried out in a swinging motion, while on the T-01 tester in a sliding movement. Friction coefficient and wear were determined for all tests. Surface morphology testing and chemical composition analyses were performed using the Jeol JSM-7100F scanning electron microscope, equipped with an EDS microanalyzer. Surface geometry measurements prior to and after tribological tests were performed on a Taylor Hobson’s Talysurf CCI contactless optical profilometer. The optical tensiometer was used to determine the contact angles with demineralized water and Ringer’s solution. The tribological tests of the titanium alloy Ti6Al4V lead to the conclusion that implantation of N+ ions results in better tribological properties of the alloy. The best tribological characteristics were obtained for a titanium alloy implanted with nitrogen ions under technically dry friction conditions. The influence of the tribological system on Ringer’s fluid influenced the reduction of coefficients of friction in the oscillating movement (Tribometer TRB) and sliding motion (Tester T-01M). In the case of a oscillating movement, higher wear of the tested friction pair was observed under friction conditions with the Ringer solution lubrication.

PL

W artykule przedstawiono analizę wpływu implantacji jonowej na właściwości stopu tytanu stosowanego w systemach biotribologicznych. Przedmiotem badań był stop tytanu Ti6Al4V implantowany jonami azotu N+. Tribologiczne badania modelowe przeprowadzono w skojarzeniu kula z Al2O3–tarcza ze stopu Ti6Al4V implantowana jonami azotu. Eksperymentalne testy tarciowe zrealizowano na testerach typu pin-on-disc w warunkach tarcia technicznie suchego oraz tarcia ze smarowaniem roztworem Ringera. Badania na testerze TRB przeprowadzono w ruchu wahadłowym, natomiast na testerze T-01 w ruchu ślizgowym. Dla wszystkich testów określono współczynnik tarcia oraz zużycie. Przy użyciu skaningowej mikroskopii elektronowej SEM wraz z analizą składu chemicznego EDS oraz profilometrii interferometrycznej obserwowano morfologię oraz topografię powierzchni badanych próbek przed i po testach tribologicznych. Tensjometr optyczny posłużył do wyznaczenia kątów zwilżania wodą demineralizowaną oraz roztworem Ringera. Uzyskane wyniki badań pozwoliły na stwierdzenie, że zastosowanie implantacji jonowej istotnie poprawia właściwości tribologiczne stopu tytanu zarówno w warunkach tarcia technicznie suchego, jak i w warunkach smarowania roztworem Ringera. Najlepsze charakterystyki tribologiczne uzyskano dla stopu tytanu implantowanego jonami azotu w warunkach tarcia technicznie suchego. Oddziaływanie systemu tribologicznego z płynem Ringera wpłynęło na zmniejszenie współczynników tarcia w ruchu wahadłowym (Tribometr TRB) i ślizgowym (Tester T-01M). W przypadku ruchu wahadłowego większe zużycie badanych par trących zaobserwowano w warunkach tarcia ze smarowaniem roztworem Ringera.

12

Damage risk of the raceway edge arise in four-point slewing bearing

Krynke Marek, Mielczarek Krzysztof

System Safety : Human - Technical Facility - Environment

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2019

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Vol. 1, nr 1

632--638

EN

In the article some forms of damage to raceway of slewing bearings for single-row ball bearing slewing ring with four-point contact and their causes were shown. Changes of the contact angle and its influence on the geometry for contact zone of the rolling elements raceway were analyzed. An identification of changes for contact angle of individual balls for different parameters of the contact was received. It was showed that contact angles of some rolling elements were increasing. It can cause damage to the raceway by spalling or rolling out of edge of the bearing ring. Ways of avoiding too early damage to the raceway at the stage of the design and the selection of coronary bearings were suggested.

13

Influence of the surface roughness of Ti6Al7Nb alloy on its behavior in biotribological systems

Piotrowska Katarzyna, Madej Monika, Spišák Emil, Ozimina Dariusz

Journal of Machine Construction and Maintenance - Problemy Eksploatacji

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2019

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no. 3

19--29

EN

The paper presents the results of studies of Ti6Al7Nb alloy properties used in biotribological systems. The following physicochemical treatments of the alloy were compared: polishing, sandblasting, etching as well as sandblasting and etching. Element identification was performed using a scanning electron microscope equipped with an EDS microanalyser. Scanning and confocal microscopy was used to observe surface morphology and topography. Frictional tests were carried out using a ball-disk coupling in reciprocating motion in technically dry friction and friction with lubrication with Ringer’s solution. An optical tensiometer was used to determine the contact angle. As a result of the applied physicochemical treatments, surfaces of different morphology and geometric surface structure were obtained. The polished and etched sample had the most homogeneous surface. It was found that surface roughness significantly influences tribological properties. For the samples characterized by micro roughness of the surface, the best characteristics were obtained under conditions of technically dry friction. However, under the conditions of lubrication with Ringer's solution, the properties were the best for the samples characterized by nanoroughness. Ringer's solution reduced resistance to motion by approximately 20%. A negative influence of surface development on wetting was also found.

PL

Przedstawiono wyniki badań właściwości stopu Ti6Al7Nb stosowanego w systemach biotribologicznych. Porównano ze sobą stop poddany następującym obróbkom fizykochemicznym: polerowaniu, piaskowaniu, trawieniu oraz piaskowaniu i trawieniu. Za pomocą mikroskopii skaningowej i konfokalnej obserwowano morfologię i topografię powierzchni. Identyfikację pierwiastków wykonano przy użyciu skaningowego mikroskopu elektronowego wyposażonego w mikroanalizator EDS. Badania tarciowe zrealizowano w skojarzaniu kula–tarcza w ruchu posuwisto-zwrotnym w warunkach tarcia technicznie suchego oraz tarcia ze smarowaniem płynem Ringera. Do wyznaczenia kąta zwilżania wykorzystano tensjometr optyczny. W wyniku zastosowanych obróbek fizykochemicznych uzyskano powierzchnie o zróżnicowanej morfologii oraz strukturze geometrycznej powierzchni. Najbardziej jednorodną powierzchnią charakteryzowała się próbka polerowana oraz trawiona. Stwierdzono, że chropowatość powierzchni znacząco wpływa na właściwości tribologiczne. Dla próbek charakteryzujących się mikrochropowatością powierzchni uzyskano najlepsze charakterystyki w warunkach tarcia technicznie suchego. Natomiast w warunkach smarowania płynem Ringera były one najlepsze dla próbek wyróżniających się nanochropowatością. Płyn Ringera wpłynął na zmniejszenie oporów ruchu o około 20%. Wykazano również negatywny wpływ rozwinięcia powierzchni na zwilżalność.

14

Adhesive bonding of elements made using the Multi Jet Fusion additive technique

Bednarek Sandra, Sokołowski Paweł, Piwowarczyk Tomasz, Ambroziak Andrzej, Nowak Krzysztof, Janowicz Karol

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2019

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Vol. 63, No. 5

93--100

EN

The research discussed the application potential of adhesive bonding in the joining of 3D printed structures made using the Multi Jet Fusion (MJF) state-of-the-art additive technology (HP). The research involved the performance of technological tests aimed to assess the adhesive properties of 3D printout surfaces in the function of a surface layer treatment method as well as to evaluate adhesives used in the joining of 3D printed structures. The tests performed within the research included roughness measurements, contact (wetting) angle measurements, peel strength tests, shear strength tests and bend tests. The results obtained in the tests made it possible to assess the joinability of MJF printouts as well as to identify reasons for problems accompanying the joining of such elements.

PL

Analizowano potencjał aplikacyjny techniki klejenia do łączenia struktur drukowanych 3D w nowoczesnej technologii addytywnej Multi Jet Fusion (MJF) firmy HP. Przeprowadzono badania i testy technologiczne, na bazie których oceniano właściwości adhezyjne powierzchni wydruków 3D, w funkcji metody obróbki warstwy wierzchniej. Oceniano również zastosowane kleje, przeznaczone do spajania drukowanych struktur 3D. W tym celu przeprowadzono pomiary chropowatości, pomiary kąta zwilżania, badania wytrzymałości na odrywanie, badania wytrzymałości na ścinanie i próby zginania. Na podstawie uzyskanych wyników oceniono możliwości łączenia wydruków MJF oraz wskazano przyczyny problemów spajania tego typu elementów.

15

The Influence of Surface Free Energy on Tribological Properties of Oxide Layers Formed on Aluminium Alloy EN AW-5251

Niedźwiedź M., Bara M., Skoneczny W.

Tribologia

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2018

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nr 4

71--79

EN

This paper presents the influence of the parameters of the formation of oxide layers on the surface free energy and the tribological properties of these layers. The layers were formed electrochemically on aluminium alloy EN AW-5251, with variable values of electrolyte temperature and current density. A three-component electrolyte was used to produce oxide layers. The surface free energy was determined by the droplet deposition method by measuring the wetting angles, while the van Oss-Chaunhury-Good method was used for the calculations. Tribological tests were performed on a T-17 tribological tester under conditions of technically dry friction for reciprocating motion. T7W composite was used as a specimen in tribological tests.

PL

W artykule przedstawiono wpływ parametrów wytwarzania warstw tlenkowych na swobodną energię powierzchniową oraz właściwości tribologiczne tych warstw. Warstwy zostały wytworzone na stopie aluminium EN AW-5251 metodą elektrochemiczną, przy zmiennych wartościach temperatury elektrolitu oraz gęstości prądowej. Do wytwarzania warstw tlenkowych zastosowano elektrolit trójskładnikowy. Swobodna energia powierzchniowa wyznaczona została metodą osadzonej kropli poprzez pomiar kątów zwilżania, natomiast do obliczeń zastosowano metodę van Ossa-Chaunhury’ego-Gooda. Testy tribologiczne przeprowadzono na testerze tribologicznym T-17 w warunkach tarcia technicznie suchego dla ruchu posuwisto-zwrotnego. W testach tribologicznych jako próbki użyto kompozytu T7W.

16

Ocena właściwości elastomerów wykorzystywanych na smoczki dziecięce w badaniach przyspieszonego starzenia

Żelasko A., Mrowiec A., Światłoń M., Niedziela E., Walaszczyk M., Zielińska E., Łagan S.

Aktualne Problemy Biomechaniki

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2018

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z. 15

67--74

PL

Celem pracy była ocena wpływu procesu przyspieszonego starzenia materiałów wykorzystywanych do produkcji smoczków dziecięcych, na zmianę właściwości powierzchni na podstawie pomiarów kąta zwilżania. Wyznaczona swobodna energia powierzchniowa (SEP) oraz jej składowe wskazują na wyraźny wpływ parametrów procesu starzenia na właściwości powierzchni smoczków lateksowych i silikonowych. Badania ujawniły znaczące różnice w kierunkach zmian SEP na skutek zjawiska starzenia. Uważa się, iż ma to wpływ na inicjowanie zjawiska adhezji bakterii.

EN

The aim of the study was to assess the impact of the accelerated aging of materials for baby’s pacifiers, on the surface properties based on wetting measurements. The research method consisted in assessing the contact angle in the sitting drop procedure based on the analysis of its shape in the subsequent stages of the aging process. For each stage and material, the value of surface free energy (SEP) was determined, which was also subjected to statistical analysis. Analytical model of Owens-Wendt was used for the calculations.

17

Ocena odporności korozyjnej stopu TI-6AL-4V po obróbce strumieniowo-ściernej stosowanym w protetyce stomatologicznej

Zapart M., Krawczyk C., Radwin E., Czerwik M., Sarraj S.

Aktualne Problemy Biomechaniki

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2018

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z. 16

41--46

PL

Niniejsza praca dotyczy badań odporności korozyjnej stopu Ti-6Al-4V o zmodyfikowanej powierzchni poprzez obróbkę mechaniczną (szlifowanie, polerowanie oraz obróbka strumieniowo-ścierna) do zastosowań w protetyce stomatologicznej. W ramach pracy przeprowadzono pomiar kąta zwilżania oraz badania odporności na korozje wżerową i szczelinową. Uzyskane wyniki jednoznacznie wykazały, że niezależnie od rodzaju modyfikacji powierzchni stop Ti-6Al-4V ma charakter hydrofilowy i jest odporny na korozję wżerową i szczelinową.

EN

This work concerns tests of corrosion resistance of Ti-6Al-4V alloy with modified surface by mechanical treatment (grinding, polishing and abrasive blasting treatment) for applications in dental prosthetics. As part of the work, was measured the contact angle as well as the pitting and crevice corrosion resistance tests. Obtained results clearly showed that regardless of the type of surface modification, the Ti-6Al-4V alloy is hydrophilic and resistant to pitting and crevice corrosion.

18

The Effect of Active Diluent Addition on the Energy and Adhesive Properties of Epoxy Adhesive

Krawczuk Anna, Domińczuk Jacek

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 1

19--25

EN

The paper reports values of surface free energy and its components of an epoxy adhesive modified by the addition of an active diluent. Wetting envelopes are determined and they serve as a basis for a wettability analysis and determining the possibility of maximizing the work of adhesion between the liquid and the solid. Static strength tests of adhesive joints made with the analysed adhesive compositions were also conducted. The results are used to determine the effect of active diluent addition on the energy and adhesive properties of the epoxy adhesive

19

Analiza właściwości energetycznych kompozycji klejowych dedykowanych do połączeń klejowo-zgrzewanych

Krawczuk A., Domińczuk J.

Technologia i Automatyzacja Montażu

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2017

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nr 2

61--65

PL

W pracy przedstawiono wyniki badań swobodnej energii powierzchniowej kompozycji klejowych, utworzonych w celu zapewnienia właściwych warunków wypełniania szczelin w połączeniach hybrydowych, takich jak połączenie klejowo-zgrzewane. Przedstawiona w pracy analiza wartości składowych polarnej i niepolarnej dla badanych klejów posłużyła do określenia zdolności kleju do zwilżania powierzchni. Podstawą do określenia wartości składowych swobodnej energii powierzchniowej były pomiary kąta zwilżania przez wybrane substancje adhezyjne na materiale o znanym stanie energetycznym warstwy wierzchniej. W oparciu o przeprowadzoną analizę możliwe było sklasyfikowanie kompozycji wg ich właściwości energetycznych, sprzyjających procesowi zwilżania powierzchni łączonych materiałów.

EN

The paper presents the results of measurements of surface free energy for adhesive compositions created in order to provide the appropriate conditions for filling gaps in the hybrid joints, such as weld-bonded joints. Presented in the paper analysis of polar and non-polar components of surface free energy for the studied adhesives was used to determine the ability of the adhesive to wet the surface. The basis for determining the value of surface free energy were measurements of the contact angle by selected adhesive substances on the material with a specific energy state of the surface layer. Based on this analysis, it was possible to classify the composition according to the energy properties conducive to the process of wetting the surface of the joined materials.

20

Fabrication, properties and cytotoxicity evaluation of degradable poly(trimethylene carbonate-co-lactide) for the use as nerve guidance channels

Bednarz P.

Tarnowskie Colloquia Naukowe. Nauki Techniczne i Ścisłe

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2017

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T. 4, nr 3

39--48

EN

Strategies to improve healing of damaged nerves include the application of specialized nerve guides, which hold the promise for allowing reanastomosis of the severed or damaged fibers. Studies have demonstrated that the use of a slowly degradable polymeric nerve guide can improve the nature and rate of nerve regeneration across a short gap in small nerves. The objective of this study was to characterize a biodegradable nerve guide based on poly(trimethylene carbonate-co-lactide) for peripheral nerve regeneration and to evaluate its cytotoxicity. The obtained copolymer films were incubated in two different media (distilled water and simulated body fluid), and while the degradation process appeared, pH and ion conductivity changes of solutions were monitored as well as mass loss of the samples. Additionally, mechanical tests (tensile strength, elongation at break and Young’s modulus parameters) before and after different time points were carried out. To evaluate cytotoxicity biological test were done on fibroblasts cells (NIH 3T3). Cell metabolic activity was determined using Alamar Blue reagent and their morphology was observed under fluorescence microscopy. The growth of pH in both media were mostly caused by steadily degradation of carbonate units into alkaline diols. The growth of ion conductivity value at the beginning of the incubation process was associated with the releasing of free ions to the solution. The mechanical parameters decreased with the progress of degradation process. Ringer’s fluid, as more aggressive, caused higher decrease in mechanical properties. The measured contact angles showed good surface wettability. Both surfaces, the top and the bottom, had similar hydrophilicity. Moreover, activity of fibroblasts cells were similar on both sides as well as on the reference TCPS. Good adhesion of NIH 3T3 cells to the surface suggests that the hydrophilic polymers promote colonization of fibroblasts cells on their surface. Biological studies have shown that used cells are very sensitive to surface topography which they colonize and cell viability was higher at the bottom surface, which has a slightly higher average roughness Ra. Thus, fibroblasts cell preferred colonizing rougher than smoother surfaces. Fabricated films does not affect negatively, namely, toxic on cell cultures and forms substrate with favourable surface properties. This was confirmed by the Alamar Blue tests and microscopic observations.