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1

Application properties and microscopic analysis of elastomer samples cross-linked by gamma radiation

Bonato Jasminka

Zeszyty Naukowe Politechniki Morskiej w Szczecinie

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2024

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nr 78 (150)

15--21

EN

Natural rubber is an important industrial material derived from caoutchouc trees (Hevea Brasiliensis). By chemical composition, it is a polymer material that is mostly cis-1,4-polyisoprene. It falls into the category of elastomers, which enables its wide usage due to its specific characteristics. Polymer materials include plastic, rubber, and glue and are the most important technical materials. Rubbers are used in the production of conveyor belts, shock absorbers, coatings, fenders, engines, and device parts. They are also used in composite materials such as threads, particles, and matrix materials. By analyzing the properties of natural rubber, the subject of the research is defined, i.e., the characterization of natural rubber samples and their connection with macroscopic properties. In accordance with the subject of the research, in this paper, tests are carried out on samples of natural rubber, which are obtained in the form of thin films from latex and cross-linked by gamma radiation. A total dose of 300 kGy is applied to the samples in the state of uniaxial deformation. In this sense, a hypothesis is put forward that involves examining the influence of radiation dose on the morphology of natural rubber samples using scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDX). The investigation aims to emphasize the importance of the method in acquiring a comprehensive characterization of the material samples, which are used both in maritime areas and in other fields of application.

2

Wstępne rozpoznanie hałdy w Wałbrzychu w rejonie Kopalni Victoria

Zielińska Amelia, Piróg Kamil

Górnictwo Odkrywkowe

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2021

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R. 62, nr 2

33--36

PL

W artykule przedstawiono działania „ Poltegor-Instytut” w ramach projektu MINRESCUE „Od odpadów wydobywczych po cenne zasoby: nowe koncepcje gospodarki o obiegu zamkniętym”. Przeprowadzono wstępne rozpoznanie hałdy zlokalizowanej w Wałbrzychu polegające na wykonaniu odwiertów, pobraniu próbek, a następnie poddaniu ich wstępnym analizom składu jakościowo-ilościowego.

EN

The paper presents the activities of „Poltegor-Instytut” realized within „From Mining Waste to Valuable Resource: New concepts of the Circular Economy” MINRESCUE. A preliminary reconnaissance of the heap located in Wałbrzych was carried out, consisting in drilling boreholes, taking samples and then subjecting them to preliminary analyzes of their qualitative and quantitative composition.

3

Structural and optical properties of Dy3+ doped Sr2SiO4 phosphors

Verma Durga, Patel R. P., Verma Mohan L.

Materials Science Poland

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2019

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Vol. 37, No. 1

55--64

EN

Dysprosium doped strontium silicate phosphor namely (Sr2SiO4:Dy3+) was prepared by low-temperature solution combustion method using urea (CO(NH2)2) as a fuel. The material was characterized by powder X-ray diffraction (XRD), FT-IR, SEM and EDX. The average crystallite sizes was calculated by Scherer formula. Thermoluminescence study was carried out for the phosphor which showed single glow curve. The kinetic parameter were calculated by using Chen’s glow curve method. Photoluminescence spectra revealed strong transition at 473 nm (blue), 571 nm (yellow) and weak transition at 645 nm (red). These peaks were assigned to transition 4F9/2 → 6H15/2, 13/2 , 11/2. CIE graph of Sr2SiO4:Dy3+phosphor is suitable for the generation of white light emission.

4

Microstructure and Phase Composition of the Ag-Al Film Wear Track: Through-Thickness Characterization by Advanced Electron Microscopy

Kryshtal O., Kruk A., Mao F., Taher M., Jansson U., Czyrska-Filemonowicz A.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 1

251--256

EN

Analytical transmission electron microscopy has been applied to characterize the microstructure, phase and chemical composition of the Ag–Al wear track throughout its thickness down to the atomic level. Microscopy findings have been correlated with Ag–Al film tribological properties to understand the effect of the hexagonal solid solution phase on the tribological properties of this film. Ag–25Al (at.%) films have been produced by simultaneous magnetron sputtering of components in Ar atmosphere under 1 mTorr pressure and subjected to pin-on-disc tribological tests. It has been shown that hcp phase with (001) planes aligned parallel to the film surface dominates both in as-deposited and in tribofilm areas of the Ag–Al alloy film. Possible mechanisms of reduced friction in easily oxidized Ag–Al system are discussed and the mechanism based on readily shearing basal planes of the hcp phase is considered as the most probable one.

5

Synthesis and characterization of AA5083 and AA2024 reinforced with SiO2 particles

Raja R., Jannet S., Thampy M. A.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2018

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Vol. 66, nr 2

127--132

EN

Among the types of different particulates, silica is a standout as one of the the cheapest and low-density particulates accessible in substantial amounts. The present study has been centered around the synthesis and study of aluminum matrix composite strengthened with nano-sized SiO2 particles of various weight percentage by means of the stir casting technique. The EDX emphasized the presence of various elements and augmented the in situ reaction. The tensile strength and wear studies were also carried out. The reinforcement materials percentage variation was one of the important factors for the present studies. The Aluminum Alloy 5083 and 2024, which are magnesium and copper-based alloys, had a significant effect on the material characterization.

6

Antimicrobial Characteristics of Pulsed Laser Deposited Metal Oxides on Polypropylene Hydroentangled Nonwovens for Medical Textiles

Ramamurthy P., Chellamani K. P., Dhurai B., ThankaRajan S. P., Subramanian B., Santhini E.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 2 (122)

112--119

EN

In this study, an attempt was made to investigate the antimicrobial activity on polypropylene (PP) hydroentangled nonwoven fabrics coated with transition metal oxides. After etching the nonwoven fabrics with RF plasma, nano-scale coatings of ZnO and CuO were done using the KrF excimer based pulsed laser deposition technique (PLD). Morphological and antimicrobial studies were carried out to elucidate the mechanism of antibiocidal behaviour of the coated fabrics. Results showed significant antibacterial activity of ZnO and CuO coated PP hydroentangled nonwovens with a better activity against gram positive S.aureus than gram negative E.coli. Inherently non-toxic, PP has excellent chemical resistance and the use of specialised PP fibres for hydroentangled nonwovens could offer scope in addition to metal oxide coatings; nano-scale biological materials such as enzymes and drugs could add specific functionality for their use as medical textiles.

PL

W pracy podjęto próbę zbadania aktywności przeciwdrobnoustrojowej polipropylenowych włóknin pokrytych tlenkami metali. Przeprowadzono badania morfologiczne i przeciw- drobnoustrojowe powlekanych włóknin. Wyniki wykazały znaczną aktywność antybakteryjną włóknin pokrytych ZnO i CuO, przy czym wyższą aktywność antybakteryjną zaobserwowano wobec bakterii Gram-dodatnich (Staphylococcus ureus), niż wobec Gram-ujemnych (Escherichia coli). Stwierdzono, że zastosowanie nietoksycznego polipropylenu, który charakteryzuje się bardzo dobrą odpornością chemiczną, do wytwarzania włóknin powlekanych tlenkami metali pozwala na otrzymanie funkcjonalnych produktów medycznych.

7

Comparison of float-sink and progressive release flotation of ground products of coal middlings

Xie W., He Y., Luo C., Zhang X., Li H., Yu J., Wang H., Shi F.

Physicochemical Problems of Mineral Processing

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2015

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Vol. 51, iss. 2

675--684

EN

An additional recovery of coking coal middlings can be utilized for increasing of the concentrate yield of coking coal. A combined flow sheet of comminution and flotation can realize this target. To investigate the effect of grinding process on further flotation of ground products, progressive release flotation tests were used to compare with the float-sink tests, which were regarded as a criterion. Coal middlings were ground by wet-milling with iron balls to <0.5 mm. Curves of ash vs. cumulative yields of sized products indicated that the concentrate yield of coal separated by progressive release flotation was lower than that of coal benefited by the float-sink test, with the same ash for four size fractions (0.5-0.25 mm, 0.25-0.125 mm, 0.125-0.074 mm and <0.074 mm). Distributions of elements conducted by energy disperse spectroscopy (EDX) showed that associated kaolinite was liberated and exposed on the surface. It led to the shift of local surface property from hydrophobicity to hydrophilicity. Meanwhile, analyses of chemical property performed by an X-Ray photoelectron spectrometer (XPS) depicted that the hydrophilic mineral FeOOH, which generated in the grinding process, was adsorbed on the coal surface. Flotation of the ground products were worsened due to the increase of hydrophilicity of the coal surface.

8

Application of Aloe vera gel instead of silicon dioxide as organic dielectric material in microelectronics

Rana S. M., Al-Amin R., Uz-Zaman A., Talukder S. H., Mia N. H., Tayyaba S., Hoq M.

Materials Science Poland

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2015

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Vol. 33, No. 3

635--638

EN

Organic materials are now being used in a wide range of microelectronic applications in parallel with inorganic materials, because of their superior properties, environmental safety, and low cost. This paper describes the characterization of Aloe vera gel (AVG), a new organic dielectric material. The surface morphology, spatial distribution of elements, and structural characteristics of an AVG layer were examined using scanning electron microscopy, energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD), respectively. The resistance of the AVG layer, determined using a four-probe station, was 640 Omega. EDX showed that the elements contained in the layer were carbon, oxygen, aluminum, silicon, calcium, potassium, and copper. The XRD results suggested that the sample primarily consisted of bornite (Cu5FeS4), geerite (Cu8S5), sal ammoniac (NH4Cl), and carobbite (KF).

9

Method of determination of palladium concentration for C-Pd nanostructural films as a function of film thickness, roughness and topography

Rymarczyk J., Kozłowski M.

Materials Science Poland

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2014

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Vol. 32, No. 2

228--235

EN

In this paper a method of determination of Pd in a carbon-palladium film (C–Pd film) deposited on a quartz substrate is presented. This method is based on energy dispersive X-ray spectroscopy (EDX) and all experiments were performed using a scanning electron microscope (SEM) equipped with EDX system. Qualitative and quantitative analyses were carried out for C–Pd films prepared by PVD method in different technological conditions. It was shown that results of the experiments depended on the structural model, film thickness and electron beam energy used for Pd content calculation. This method enabled us to conclude on the homogeneity of palladium distribution in the whole volume of carbonaceous matrix, depending on the parameters of PVD process. Additionally, these studies showed that a different palladium concentration in C–Pd films had a significant impact on their topography and morphology.

10

Preparation and characterization of mixed-matrix-membranes

Hülagü D., Kramer V., Kraume M.

Czasopismo Techniczne. Mechanika

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2012

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R. 109, z. 1-M

95--105

EN

In the concept of mixed-matrix-membrane (MMM) producing, rubbery polymer PDMS and a micro porous carbon adsorbent have been chosen as membrane components. Transport properties of MMMs strongly depend on the polymer and filler interface. Blockage of the carbon pores by polymer chains eliminates the necessary mass transfer. As a fundamental step in preparation pore blockage was investigated for different carbon treatments. Polymer penetration into the pores was analysed by Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDX). By using saturation method of carbon particles with a solvent pore blockage with silicon chains was hindered partly.

PL

Jako składniki membrany w koncepcji wytwarzania membran wielomatrycowych (MMM) wybrano polimer gumy PDMS oraz mikroporowaty adsorbent węgla. Właściwości MMM w zakresie przenoszenia zależą w dużej mierze od obszaru wzajemnego oddziaływania polimeru i materiału wypełniającego. Blokada porów węgla za pomocą łańcuchów polimerowych eliminuje konieczność przenoszenia masy. Blokada porów została potraktowana jako najważniejszy etap przygotowań pod kątem poddawania węgla działaniu różnych środków. Przenikanie polimerów do porów przeanalizowano w ramach mikroskopii elektronowej skaningowej (SEM) oraz rentgenowskiej spektroskopii energii dyspersyjnej (EDX). Zastosowanie metody saturacji cząsteczek węgla z rozpuszczalnikiem pozwoliło częściowo powstrzymać blokadę porów z łańcuchami krzemu.

11

Formation of Boric Acid by Surface Oxidation of Amorphous Boron Powder: Characterization and Quantitative Estimation

Nandi A. K., Ghosh M., Newale S. P., Jadhav A. J., Prasanth H., Pandey R. K.

Central European Journal of Energetic Materials

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2012

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Vol. 9, nr 4

387-398

EN

Amorphous Boron Powder (ABP) is used as a fuel in air breathing propulsion systems due to its high gravimetric and volumetric heat value. ABP is sensitive to air and undergoes slow oxidation during storage and handling, leading to the formation of a boric acid layer on the particle surface. This paper describes an analytical method for the estimation of boric acid in ABP. In-house samples obtained from the pilot plant of this laboratory, as well as commercial samples, were assayed for their boric acid content. The study is substantiated by characterization of the ABP samples by SEM with EDX and FTIR. The ageing characteristics of in-house boron powder was also studied.

12

Utlenianie stali Crofer22APU w atmosferze pary wodnej

Żurek Z., Homa M., Jaroń A., Stawiarski A.

Ochrona przed Korozją

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2011

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nr 6

349-351

PL

W pracy przedstawiono wyniki badań utleniania stali Crofer22APU w atmosferze pary H2O w zakresie temperatur 600-900oC w czasie 100 godzin. Na podstawie wyników badań stwierdzono, że proces utleniania przebiega zgodnie z prawem parabolicznym. Szybkość utleniania jest funkcją temperatury i wzrasta wraz ze wzrostem temperatury. Wielkość stałej szybkości utleniania w parze wodnej jest porównywalna ze stałą szybkości utleniania otrzymaną w powietrzu. Utworzone zgorzeliny w badanym zakresie temperatur wykazują dobrą przyczepność do podłoża.

EN

In this paper the results of oxidation of Crofer22APU steel in water vapor at the temperature range 600-900oC during 100 hours are presented. Oxidation process obeys with parabolic rate low. Oxidation rate is a function of temperature and increases with increasing temperature. The kp of oxidation in water vapor is comparable with the kp obtained in the air. Scales shows good adhesion to the substrate.

13

Brazing a graphite composite to molybdenum alloy TZM using active copper-based filler metals with chromium additive

Mirski Z.

Archives of Metallurgy and Materials

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2011

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Vol. 56, iss. 3

829-837

EN

The paper presents issues of brazing the graphite composite CFC 222 with the molybdenum alloy TZM. Both materials demonstrate significant differences in physicochemical and mechanical properties that significantly affect brazing conditions and properties of the brazed joints. The performed brazing operation was preceded by a wettability test that decided selection of the filler metal. From among various copper-based filler metals, the best appeared a copper brazing filler metal with some addition of active chromium. Presented is a model of the wedge test, helpful at optimising the brazing process of two materials with different properties. Width of the brazing gap was selected on the ground of metallurgical examinations after the wedge test and transferred to the joint with a parallel gap. Applied were various forms of copper-based filler metals in that chromium was present as an alloying component, a component of the brazing paste, powder between copper covers and as a galvanic coating of a pure-copper strip. Evaluation of brazed joints of the composite CFC 222 with the TZM alloy is presented on the grounds of metallographic examinations by means of light microscopy and microhardness measurements, electron microscopy, EDX analysis of elements and XRD analysis of phase composition of the reactive zone.

PL

W pracy przedstawiono problematykę lutowania twardego kompozytu grafitowego CFC 222 ze stopem molibdenowym TZM. Obydwa materiały wykazują znaczne różnice we właściwościach fizykochemicznych i mechanicznych, które mają istotny wpływ na warunki lutowania i właściwości uzyskanych połączeń lutowanych. Wykonanie połączeń poprzedziła próba zwilżalności, która zdecydowała o wyborze lutu. Spośród różnych lutów na osnowie miedzi najlepszy okazał się lut miedziany z dodatkiem aktywnego chromu. Przedstawiono model próby klinowej, pomocny w optymalizacji procesu lutowania obydwu materiałów zróżnicowanych właściwościach. Na podstawie próby klinowej, w wyniku badań metalograficznych, dobrano szerokość szczeliny lutowniczej i przeniesiono ją na złącze ze szczeliną równoległą. Stosowano różne postacie lutów miedzianych, w których chrom występował jako składnik stopowy, składnik pasty lutowniczej, proszek między okładkami miedzianymi i jako pokrycie galwaniczne taśmy z czystej miedzi. Ocenę połączeń lutowanych kompozytu CFC 222 ze stopem molibdenowym TZM przedstawiono na podstawie badań metalograficznych za pomocą mikroskopii świetlnej i pomiarów mikrotwardości, mikroskopii elektronowej, analizy pierwiastków metodą EDX oraz analizy składu fazowego strefy reakcyjnej metodą dyfrakcji rentgenowskiej XRD.

14

Kompozyty metaliczne wytwarzane metodą mechanicznej syntezy — przykład układu Al-Mg-ZrSi2

Błaż L., Kula A., Sugamata M., Kaneko J.

Rudy i Metale Nieżelazne

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2007

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R. 52, nr 11

823-828

PL

Przedstawiono skrótowy przegląd badań lekkich kompozytów metalicznych na osnowie Al i stopu Al-Mg wytwarzanych w ramach współpracy badawczej Nihon University w Tokio i Akademii Górniczo-Hutniczej. Od 1998 roku prowadzone są badania kompozytów zawierających 8÷19 % tlenków metali ze szczególnym uwzględnieniem wpływu temperatury na strukturę i własności materiału. Reakcja chemiczna w podwyższonej temperaturze może spowodować redukcję tlenków (Me-O) i zmiany struktury prowadzące do utworzenia tlenków aluminium lub złożonych faz Al(Mg)-O. Wyróżniono dwie podstawowe grupy kompozytów: (1) materiały, w których zredukowany metal (Me) jest praktycznie nierozpuszczalny w osnowie, oraz (2) materiały, w których uwolniony Me tworzy fazy międzymetaliczne z metalem osnowy. Istotnym problemem w produkcji kompozytów jest porowatość pojawiająca się przede wszystkim w wyniku reakcji chemicznej zależnie od lokalnej zmiany objętości składników i produktów reakcji w stanie stałym. W poszukiwaniu nowych składników umacniających kompozyty zwrócono uwagę na inne związki metali, które nie powodują nadmiernego utleniania osnowy, tak jak w wyniku redukcji tlenków. Wstępne badania zostały przeprowadzone dla kompozytu Al(Mg)-ZrSi2. Stwierdzono, że reakcja chemiczna między składnikami podczas wyżarzania lub odkształcania w podwyższonej temperaturze nie prowadzi do nadmiernych zmian silnie rozdrobnionej struktury materiału. Wielkość obserwowanych w osnowie dyspersyjnych tlenków typu Al-Mg-O nie ulega praktycznie zmianie nawet po przetopieniu kompozytu.

EN

Brief overview through research work on light-metal based composites developed at Nihon University, Tokyo and tested at AGH — University of Science and Technology according to bilateral research cooperation program is presented. Since 1998 a number of experiments were performed on aluminum and aluminum-magnesium based composites containing 8÷10 % other metal oxides in order to test the effect of temperature on the material structure and properties. Chemical reaction between the composite components at high enough temperature result in reduction of Me-oxides and development of very fine Al- and Al(Mg)-oxides within the matrix. In general, two groups of composites were distinguished: (1) composites containing Me-elements that are insoluble in Al-matrix and (2) composites containing Me-elements that create Al-Me or Al-Mg-Me intermetallics. Material porosity was found to depend on local volume contraction during chemical reaction as well as following intermetallic grains growth and related contraction/expansion effect. Searching for new hardening components was undertaken in order to select oxygen-free hardening components that avoid excessive oxidation of the matrix that result from chemical reaction at high temperature. Preliminary experiments were performed on Al(Mg)-ZrSi2 composite. It was observed that heavy refined structure of mechanically alloyed composite was practically unchanged during annealing even if some structural processes from chemical reaction between components were observed. Very fine Al(Mg)-O particles, that developed in the composite matrix, were practically stable in their size even if the material was re-melted above the matrix liquidus temperature.

15

The study of silver nanoparticles by scanning electron microscopy, energy dispersive X-ray analysis and scanning tunnelling microscopy

Puchalski M., Dąbrowski P., Olejniczak W., Krukowski P., Kowalczyk P., Polański K.

Materials Science Poland

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2007

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Vol. 25, No. 2

473--478

EN

The authors present results of studies on commercially available silver nanoparticles fabricated by Amepox Microelectronics and delivered in the form of silver powder. The studies were carried out by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and scanning tunnelling microscopy (STM). Chemical analysis performed with the use of EDX revealed that the powder contains about 74% of silver. Further studies of the silver granulate by use of SEM explicitly indicated the presence of micromete-size conglomerates composed of much smaller particles. Silver powder was dissolved in n-hexane, and colloid solution was obtained, in which the particles were subjected to the process of segregation. The colloid, obtained with this method, in which one expected to find particles of smaller sizes, was deposited on the Au(111) surface. The results of the studies of the sample prepared by means of STM enabled us to estimate the distribution of silver nanoparticles size, which appeared to be normal with a relatively small standard deviation.

16

Quality of bimetal Al-Cu joint after explosive cladding

Berski S., Stradomski Z., Dyja H.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

|

Vol. 22, nr 1

73-76

EN

Purpose: An analysis of quality of bimetallic joint between aluminium and copper layers of billet for extrusion process is the subject of the work. Design/methodology/approach: For preparing the quality analysis of particular layer of bimetal, the shearing test were done. During the tests the maximal stress for particular sets of the bimetal was established. For chosen cases the metallographic research of Al-Cu joint were done. Findings: The geometry of the cylindrical set and explosive cladding process parameters which allow to obtain the cylindrical bimetallic billets without cracks and delaminations and also with uniform cladded layer along and across the billet. Research limitations/implications: The analysis is concerning the explosive joint of pure aluminium A1995 and electrolytic copper M1E 99,97 in cylindrical sets. In the future research the analysis of this kind of joints after direct extrusion process is planning. Practical implications: The analysis could be helpful for more effective designing of the bimetal billets trough the explosive cladding process and next for the plastic working processes. Originality/value: During the extrusion process with high value of extrusion ratio the delamination of the billet layers especially on the boundary of the layers is observed, this fact causes that joint after the metal working processes has lower strength even than components of the bimetal billet. So very important task is establishing the geometry set and explosive parameters to obtain the best quality of the joint.

17

Surface Functionalization of Nonwovens by Aluminum Sputter Coating

Deng B., Wei Q., Gao W., Yan X.

Fibres & Textiles in Eastern Europe

|

2007

|

Vol. 15, no. 4 (63)

90--92

EN

Nonwoven materials have been widely used in many industries. The surface properties of nonwovens are of importance in the applications presented here. In this study, magnetron sputter coating was used to deposit functional metal aluminium (Al) nanostructures onto nonwoven material. Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and Environmental Scanning Electron Microscopy (ESEM) were employed to study the structure, topography and chemical composition of the material, respectively. The AFM results revealed the formation of functional nanostructures on the fiber surfaces. A full Energy Dispersive X-ray analysis (EDX) mounted on the ESEM was also used to detect the elemental composition of the functional fibers. EDX examination showed the change in the chemical compositions of the fiber surfaces. It was also found that the electrical resistance of aluminium (Al) sputtered nonwoven material was significantly decreased.

PL

Właściwości powierzchniowe włókna zmieniono poprzez magnetronowe napylanie powłok aluminiowych, tworząc nanostruktury na powierzchni włóknin. Dla zbadania struktury warstwy, jej topografii i składu chemicznego stosowano SEM, ESEM i AFM. Badania za pomocą AFM wykazały formowanie się funkcjonalnej nanostruktury na powierzchni włókniny. Rentgenograficzna analiza (EOX) sprzężona z ESEM również służyła dla detekcji pierwiastków zintegrowanych z funkcjonalną powierzchnią włóknin. Badania EDV uwidoczniły różnice w składzie chemicznym warstw powierzchniowych włóknin. Niezależnie od powyższych analiz, wykazano znaczne obniżenie oporności elektrycznej włóknin napylanych aluminium.

18

Struktura i właściwości mechaniczne staliwa typu 0.3C-30Ni-18Cr z dodatkami Nb i Ti

Garbiak M., Lenart S.

Inżynieria Materiałowa

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2003

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R. XXIV, nr 6

674-676

PL

W pracy omówiono zmiany w strukturze i właściwościach mechanicznych staliwa typu 0.3%C-30%Ni-18%Cr wywoływane stabilizowaniem stopu dodatkami niobu i tytanu. Zawartość niobu w trzech badanych stopach wynosiła kolejno 0.0, 0.55 i 1.75 a tytanu odpowiednio 0.03, 0.28 i 0.93% mas. Mikrostrukturę stopów badano za pomocą mikroskopii świetlnej, mikroanalizy metodą EDX oraz dyfrakcji rtg z izolatów. W badanych stopach, w zależności od ich składu chemicznego, stwierdzono obecność węglików typu M23C6 i MC a także fazy G. Pomiary właściwości mechanicznych stopów w temperaturze otoczenia i 900 stopni Celsjusza wykazały niższe wartości parametrów R0.2, Rm i A10 przypadku stopów stabilizowanych.

EN

The study discusses the changes in microstructure and mechanical properties of cast steel 0.3%C-30%Ni-18%Cr due to stabilization with niobum and titanium. The niobum content in three tested alloys was 0.0, 0.55 and 1.75 and that of titanium 0.03, 0.28 and 0.93 (wt%) respectively. Microstructure was examined using light and a scanning electron microscope with EDX attachment and X-ray diffraction of residues from annealed alloys. The following phases, depending on chemical composition of cast steel, where identified: carbides of M23C6 and MC type and a G phase. The mechanical properties such as R0.2, Rm, and A10 were examined at both ambient and temperature of 900 degrees centigrade. Stabilized alloys had lower values of those parameters.

19

Laser damage threshold of GaAs' (001) surface

Rożniakowski K., Walocha J., Wojtatowicz T.W.

Scientific Bulletin. Physics / Lodz University of Technology

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2001

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Vol. 21

105-117

EN

The paper presents the investigations on the interaction of Nd:YAG pulsed laser beam with polished (001) surface of GaAs crystal. From the investigations made with scanning electron microscope it arises, that the scratches on the sample's surface resulting from the polishing process are centres (germs) of melting, since they lower the melting (damage) threshold of a surface layer.

PL

W artykule przedstawiono badania oddziaływania promieniowania lasera impulsowego Nd:YAG z wypolerowaną powierzchnią (001) kryształu GaAs. Z badań wykonanych za pomocą skaningowego mikroskopu elektronowego wynika, że rysy na powierzchni próbki powstałe w wyniku polerowania stanowią centrum procesu topienia, gdyż obniżają próg topnienia (zniszczenia) warstwy powierzchniowej.