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1

Structural Characterization and Properties of Al/Fe Multi-Layer Composites Produced by Hot Pressing

Kowalski Wojciech, Paul Henryk, Mania Izabela, Petrzak Paweł, Czaja Paweł, Chulist Robert, Góral Anna, Szlezynger Maciej

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 1

137--144

EN

This study aimed to develop Fe/Al multilayered metallic/intermetallic composites produced by hot pressing under an air atmosphere. Analyses were carried out on the composite plates made up of alternatively situated sheets of AA1050 aluminum alloy and DN04 low carbon steel, which were annealed at 903 K for 2, 5, and 10 h. Annealing was performed to obtain reaction layers of distinct thickness. The samples were examined using X-Ray diffraction and scanning and transmission electron microscope equipped with an energy-dispersive X-Ray spectrometer. To correlate the structural changes with mechanical properties, microhardness measurements in near-the-interface layers were performed. All the reaction layers grew with parabolic kinetics with η-Al5Fe2 intermetallic phase as the dominant component. After annealing for 5 and 10 hours, a thin sublayer of θ-Al13Fe4 phase was also detected.

2

Zastosowanie metod uczenia maszynowego w analizie obrazu mikroskopowego płytek ceramicznych

Gąsiński Arkadiusz, Tymowicz-Grzyb Paulina

Szkło i Ceramika

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2022

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R. 73, nr 2

34--37

PL

Współczesne metody badań stosowane w nowoczesnych technikach badawczych spowodowały, że zbierane są ogromne ilości danych, które muszą być poddane dalszej analizie. Uczenie maszynowe pomaga interpretować zgromadzone dane, a po ich przetworzeniu może pomóc podjąć dalsze decyzje. Metoda ta ma coraz większe zastosowanie w kontroli jakości wyrobów. W artykule przedstawiono zastosowanie nadzorowanej wersji uczenia maszynowego w badaniach nad optymalizacją rozpoznawania faz chemicznych z obrazów mikroskopowych i obrazów składu chemicznego dla płytek ceramicznych. Stwierdzono, że w przypadku opracowanych danych z elektronowej mikroskopii skaningowej, najlepsze wyniki uzyskano dla algorytmu CART (drzewo decyzyjne). Zastosowana metodyka znacznie usprawnia przeprowadzenie badań i poprawia jakość uzyskanych analiz obrazu w odniesieniu do standardowego oprogramowania mikroskopów.

EN

Contemporary research methods used in modern research techniques often result in the collection of huge amounts of data that must be further analyzed. Machine learning helps to interpret the collected data, and after their processing, it can help you make further decisions. The article presents the use of the supervised machine learning in research on the optimization of the recognition of chemical phases from microscopic images and chemical composition images for ceramic tiles. It was found that in the case of the developed data from scanning electron microscopy, the best results were obtained for the CART algorithm (decision tree structure). The applied methodology significantly improve the conduct of research and ameliorate the quality of the obtained image analyzes.

3

Extraction and Characterization of Silicon Dioxide from Volcanic Ash of Mount Sinabung, Indonesia: A Preliminary Study

Hasanah Moraida, Sembiring Timbangen, Sitorus Zuriah, Humaidi Syahrul, Zebua Fynnisa, Rahmadsyah

Journal of Ecological Engineering

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2022

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Vol. 23, nr 3

130--136

EN

The study was conducted on the extraction of volcanic ash from Mount Sinabung through the co-precipitation method to recover silicon dioxide (SiO2). The X-ray fluorescence (XRF) analysis showed that the SiO2 content in volcanic ash was 48.5%, and after extraction, it was 99.1%. The morphology shown by scanning electron microscope (SEM) indicated that SiO2 looks cleaner and tends to be the same size compared to the volcanic ash sample. The average particle size of volcanic ash and extracted SiO2 were 32.28571 ± 2.51259 and 12.97521 ± 0.60657 μm, respectively. The X-ray diffractometer (XRD) analysis showed that the crystal structure of the volcanic ash sample was quartz, maghemite, and cristobalite. Besides, the extracted SiO2 had an amorphous quartz crystal structure. The test conducted using Fourier transform infrared (FTIR) resulted in the absorption of 1095.57 cm-1 and 798.53 cm-1 for the Si‒O‒Si and Si‒OH groups which were the groups of siloxanes and silanols, respectively.

4

Effect of annealing on the microstructure and properties of IN 625 specimens manufactured by selective laser melting

Sitek Ryszard, Ciftci Jakub, Moszczyńska Dorota, Maj Piotr, Ura-Bińczyk Ewa, Warzybok Piotr, Cieślik Iwona, Wiśniewski Paweł, Mizera Jarosław

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e207, 2022

EN

The study examines the effect of the annealing on the microstructure, tensile strength (small flat dog-bone specimen size with 5 mm dimension of measuring base) and corrosion resistance of IN 625 nickel superalloy specimens manufactured by means of selective laser melting method (SLM). The annealing of such specimens was carried out in a chamber furnace in a protective atmosphere of argon at a temperature of 1038 °C for 1 h. The cooling process was carried out in an atmosphere of air at ambient temperature. The microstructure of the IN 625 nickel superalloy after the 3D printing process and after the post-process heat treatment (HT) was examined by means of scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The results showed a uniform microstructure after the SLM process with element microsegregation. The cooling rate in the heat treatment was not sufficient which caused precipitation at the grain boundaries, most probably carbides and resulted in only a partial increase in ductility much lower than that of the material in initial state despite the high temperature applied during the annealing. The strength in the HT was on a level comparable to as-build state, 852 MPa and 891 MPa, respectively. Additional corrosion resistance tests were performed by the potentiodynamic method in a 3.5% NaCl solution at room temperature. HT increased the current density variation from ipass due to the formed precipitates. Our studies show that the size effect is an important factor when assessing the properties of IN 625 obtained using SLM. Despite similar microstructure, the structure defects play a more significant role which translates into lower mechanical properties than in normal sized specimens defined by the standard ASTM E8.

5

Graph-based segmentation with homogeneous hue and texture vertices

Ngo Lua, Han Jae-Ho

Optica Applicata

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2021

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Vol. 51, nr 4

541--549

EN

This work presents an automated segmentation method, based on graph theory, which processes superpixels that exhibit spatially similarities in hue and texture pixel groups, rather than individual pixels. The graph shortest path includes a chain of neighboring superpixels which have minimal intensity changes. This method reduces graphics computational complexity because it provides large decreases in the number of vertices as the superpixel size increases. For the starting vertex prediction, the boundary pixel in first column which is included in this starting vertex is predicted by a trained deep neural network formulated as a regression task. By formulating the problem as a regression scheme, the computational burden is decreased in comparison with classifying each pixel in the entire image. This feasibility approach, when applied as a preliminary study in electron microscopy and optical coherence tomography images, demonstrated high measures of accuracy: 0.9670 for the electron microscopy image and 0.9930 for vitreous/nerve-fiber and inner-segment/outer-segment layer segmentations in the optical coherence tomography image.

6

Fe-Al based composite reinforced with ultra-fine Al2O3 oxides for high temperature applications

Kopec Mateusz, Jóźwiak Stanisław, Kowalewski Zbigniew

Journal of Theoretical and Applied Mechanics

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2021

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Vol. 59 nr 3

509--513

EN

In this paper, an Fe-Al based composite reinforced with ultra-fine Al2O3 oxides was obtained through sintering of aluminium, iron and mullite ceramic powders using self-propagated high temperature synthesis (SHS). The powder mixture with a 50%wt. content of the ceramic reinforcement was cold pressed and subsequently subjected to the sintering process in vacuum at 1200◦C for 25 minutes under external loading of 25 kN. The complex microstructure of the Fe-Al matrix reinforced with ultra-fine Al2O3 oxides was found to be desired in high temperature applications since only 3% of the relative weight gain was observed after 100 hours of annealing at 900◦C.

7

Influence of Hot Pressing on the Microstructure of Multi-Layered Ti/Al Composites

Kowalski Wojciech, Paul Henryk, Petrzak Paweł, Maj Łukasz, Mania Izabela, Faryna Marek

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 4

1149--1156

EN

Metal-intermetallic layered (MIL) composites attract considerable attention due to their remarkable structural and ballistic performance. This study aimed to develop a Ti/Al-based multilayered MIL material by adding ceramic powders, since they can improve the composite’s impact resistance. To this end, an experiment was conducted which a stack of alternating Ti and al sheets bonded by hot pressing; Ti/Al multilayers containing additional layers of Al2O3 and SiC powders were also produced. The samples obtained were examined using electron microscopy techniques. The clads’ mechanical properties were investigated using a Charpy hammer. In the reaction zone, only one intermetallic phase occurred: the Al3Ti phase. The model with an additional Al2O3 layer showed the highest impact energy. none of the Ti/Al clads broke during the Charpy impact test, a result proving their high ductility.

8

Halloysite intercalated by potassium acetate

Mariusz Adamczyk, Katarzyna Małycha, Karol Kułacz, Michał Pocheć, Kazimierz Orzechowski

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 6

235--243

EN

Halloysite was intercalated by the mechanochemical technique from dry components. The process efficiency of 50% was achieved. The obtained intercalate differed from the material acquired using an aqueous solution of potassium acetate. The material was analyzed employing electron microscopy, thermogravimetry, X-ray powder diffraction, and dielectric spectroscopy. It was found that the molecules and/or ions present in the interlayer spaces retain some possibility of movement. This property of the material is promising for potential application as low expensive absorbers of electromagnetic radiation.

9

Effect of upgraded field assisted sintering technology on microstructure of NiAl/CrB2 composites

Szlezynger Maciej, Maj Łukasz, Pomorska Małgorzata, Morgiel Jerzy, Jach Katarzyna, Rosinski Marcin

Composites Theory and Practice

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2020

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R. 20, nr 1

7--10

EN

The method of fabricating metal matrix composites plays a crucial role in obtaining dense materials characterized by high wear resistance. The present work describes an attempt to produce NiAl/CrB2 composites using the next generation spark plasma sintering (SPS) method, i.e. upgraded field assisted sintering technology (U-FAST) technique. Microstructure characterization was performed by means of scanning (SEM) and transmission (TEM) electron microscopy. The SEM microstructure investigations of the NiAl model material proved practically full densification of the material sintered at 1200°C and 1300°C, even if remnants of surplus nickel were observed at the boundaries of rounded NiAl grains. The NiAl/CrB2 composites, besides fused NiAl and CrB2 grains, showed the presence of a raised level of nickel also at the grain boundaries. The TEM microstructure observations helped to establish that even if the grain boundaries were pinned by nickel-rich precipitates, some increase in grain growth took place, as evidenced by the fact that strings of smaller precipitates were also visible outside the matrix grain boundaries. All these microstructure investigations indicate that the newly elaborated U-FAST technique is evidently capable of producing compacts free of porosity at lower temperatures and during a shorter time than solid hot pressing or vacuum sintering in a semiliquid state.

10

Mechanical and morphological characterization of discarded fishnet/glass fiber reinforced polyester composite

Monivarman P., Nagarajan V. A., Raj F. M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2020

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Vol. 68, nr 6

1385--1391

EN

The present work focuses on the fabrication of glass fiber and multifilament discarded fishnet nylon fiber polymer composites with four different fiber compositions. Composites are molded by means of simple hand lay-up methodology with dissimilar layers of the fiber mat. The mechanical characterization (tensile and impact) and thermal analysis of composites have to be investigated. Among the different patterns, hybrid composites reflected better tensile and impact properties as compared to the conventional materials. Morphological characterization was carried out to figure out the de-bonding of fiber/matrix adhesion characteristics of fractured face of tensile testing samples. The result suggests the potential for reuse of discarded fishnet, which constitutes a better alternative for structural work and for possible applications to be used to develop added-value products.

11

Micro-analytical studies of discontinuous precipitation in Fe-13.5 at.% Zn alloy

Zięba Paweł, Chronowski Mateusz, Morgiel Jerzy

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 3

190--196

EN

For the first time, the analytical electron microscopy has been used to determine the solute concentration profiles left behind the moving reaction front (RF) of the discontinuous precipitation (DP) reaction in a Fe-13.5 at.% Zn alloy. These profiles have been converted into grain boundary diffusivity (sδDb) values, using Cahn’s diffusion equation in its original form and the data of the growth rate of the discontinuous precipitates obtained from independent measurements. This approach has essentially removed existing difference in comparison to sδDb values obtained from Cahn′s simplified and Petermann–Hornbogen models relevant for the global approach to the DP. Simultaneously, the local values of sδDb have been up to 8–10 orders of magnitude higher than the data for volume diffusion coefficients and much greater than for diffusion at the stationary grain boundaries of Zn in pure Fe. This is clear indication that the rate controlling factor for DP reaction in the Fe-13 at.% Zn alloy is diffusion at the moving RF.

12

Silver nanoparticles deposited on calcium hydrogenphosphate – silver phosphate matrix; biological activity of the composite

Szmuc K., Kus-Liskiewicz M., Szyller Ł., Szmuc D., Stompor M., Zawlik I., Ruman T., Wołowiec S., Cebulski J.

Polish Journal of Chemical Technology

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2019

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Vol. 21, nr 2

6--13

EN

The composite containing nanosilver uniformly deposited on matrix composed of CaHPO4 x 2H2 O (brushite, ca 89 mass %), CaHPO4 (monteonite, ca 9.5 mass%), and Ag3 PO4 (0.5 mas%) was obtained by addition of calcium nitrate and silver nitrate aqueous solution at 30:1 Ca:Ag molar ratio into excess of (NH4 )2 PO4 solution at pH 5.0 – 5.5. The isolated solid was characterized by STEM, XRD, and LDI mass spectrometry. It has been found that nanosilver was uniformly distributed within composite as <10 nm diameter sized nanoparticles. Determination of silver by AAS showed that 60% of silver is present as Ag(0) nanoparticles, the present as matrix Ag3 PO4 as identified by XRD method. The composite showed strong growth inhibition in E. coli and P. aeruginosa strains, and moderate towards S. aureus. The C. albicans cells were the most resistant to the tested material, although still composite was moderately cytostatic for the yeast.

13

Wpływ innowacyjnego medium piaskującego na połączenie tytan – porcelana dentystyczna

Lubas Małgorzata

Materiały Ceramiczne

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2019

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T. 71, nr 3

276--285

PL

W pracy przedstawiono wyniki badań stanu powierzchni próbek tytanowych (Grade 2) po przeprowadzanej obróbce mechanicznej z zastosowaniem różnych mediów piaskujących. Topografię powierzchni próbek metalicznych po procesie piaskowania zobrazowano za pomocą mikroskopu sił atomowych AFM. Przeprowadzone badania pozwoliły określić podstawowe parametry chropowatości - Ra, Rq i Rmax. Do piaskowania wykorzystano mieszaninę Al2O3/NaAlSi3O8/ZrO2-TiO2 oraz tradycyjnie stosowany w pracowniach protetycznych piasek korundowy (100% Al2O3). Na podstawie badań wytrzymałościowych (metoda trzypunktowego zginania) oraz badań mikroskopowych (SEM/EDS) określono wpływ zastosowanego medium piaskującego na jakość połączenia metal-porcelana dentystyczna.

EN

The paper presents the results of tests on the surface condition of titanium samples (Grade2) after mechanical machining with the use of various sandblasting media. The topography of the surface of metallic samples was depicted after the sand blasting process by an atomic force microscope AFM. The tests allowed to determine the basic parameters of roughness - Ra, Rq and Rmax. A mixture of Al2O3/NaAlSi3O8/ZrO2-TiO2 and corundum sand (100% Al2O3) traditionally used in prosthetic laboratories was used for sandblasting. On the basis of strength tests (three-point bending method) and microscopic tests (SEM/EDS), the influence of the sandblasting medium used on the quality of the metal-dental porcelain joint was determined.

14

Hybrid ZnO/ZnO-NPs nanofibres fabricated via electrospinning

Matysiak W., Zaborowska M.

Journal of Achievements in Materials and Manufacturing Engineering

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2019

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Vol. 94, nr 1-2

5--12

EN

Purpose: Due to the growing interest and multitude of possible applications, zinc oxide nanowires, including those doped with ZnO nanoparticles, can became, alongside carbon nanotubes, a very desirable material which use is predicted in the construction of nanogenerators, dye sensitized solar cells, optoelectronics or ultrasensitive gas detectors. Design/methodology/approach: The electrospinning process allows for low-cost and scalable production of fibrous mats with diameters from a few to several hundred nanometers. What is more, electrospinning method has gained popularity also due to its versatility, now it is possible to produce fibres from almost every known polymer and the simplicity and lack of any additional functionalization of the obtained nanomaterials. The application of the calcination process to remove the polymer matrix from the obtained nanofibres results in the creation of ceramic nanofibres. Findings: Among the existing methods for the production of ceramic nanostructures, including the hydrothermal, physical and chemical vapour deposition methods, nanolithography or molecular self-assembly, the electrospinning process creates the possibility of fabricating one-dimensional nanostructures with unprecedented properties, good quality, no additional functionalization and purification. Research limitations/implications: Due to ongoing research on the potential applications of zinc oxide nanostructures, including photovoltaics, sensorics and electronics, the most predictable behaviour and properties of ZnO nanowires characterize those nanomaterials that exhibit a periodic structure of the crystal lattice. Considering the optimization of the parameters of the method of producing ceramic zinc oxide nanowires doped with crystalline ZnO nanoparticles, it is worth analysing the thermal treatment parameters of nanofibres. Practical implications: Although amorphous structure, hybrid ZnO nanofibres could be used as humidity sensors with much higher sensing properties than crystalline ZnO nanostructures. Originality/value: Low-cost, scalable production of ceramic nanofibres for most technical applications.

15

Morphology and composition of particulate matter in the air of urban area

Loskot Jan, Kumar D. Kishore, Komárek Jan, Sajdlová Světlana, Křiž Jan, Ziembik Zbigniew

Ecological Chemistry and Engineering. A

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2019

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Vol. 26, nr 1-2

59--71

EN

Atmospheric pollution by particulate matter has become increasingly important in recent years, because it was found that these airborne particles have various adverse effects on the environment and human health. To extend the knowledge of such pollutants, detailed characterization of sizes, morphology and chemical composition of individual airborne particles is desired. In the presented research, the air microparticles were taken from discarded fiberglass tape filters which are commonly used in MP101M continuous suspended particulate analysers to determine the mass concentration of the particulate matter. These samples, which were collected in Kutna Hora (Czech Republic), were studied using the methods of scanning electron microscopy and energy-dispersive X-ray spectroscopy. Based on microscopic photographs, various geometrical parameters (Feret’s diameter, perimeter, cross-section surface area, circularity, aspect ratio, roundness and solidity) of 237 particles were assessed, while the spectroscopy measurements revealed elemental composition of these particles. Statistical evaluation of the measured data was done using the methods of principal component analysis and compositional data analysis. By these methods, certain relationships among the geometrical parameters and the content of chemical elements in the particles were found. This research also demonstrated that the fiberglass air filters can easily be reused to gain additional information about airborne particles in various places at any time. The character of the particles can also provide information about a possible source of contamination.

PL

Zanieczyszczenie powietrza przez pył zawieszony (PM) staje się w ostatnich latach coraz bardziej znaczące. Stwierdzono, że unoszące się w powietrzu cząsteczki niosą różne niekorzystne skutki dla środowiska i zdrowia ludzkiego. Aby poszerzyć wiedzę na temat takich zanieczyszczeń, pożądana jest szczegółowa charakterystyka rozmiarów, morfologii i składu chemicznego poszczególnych cząstek zawieszonych w powietrzu. W prezentowanych badaniach mikrocząsteczki powietrza zostały pobrane z filtrów taśmowych z włókna szklanego, które są powszechnie stosowane w analizatorach cząstek stałych MP101M. Próbki zostały zebrane w Kutnej Horze (Republika Czeska), były badane metodami skaningowej mikroskopii elektronowej i spektroskopii rentgenowskiej z rozpraszaniem energii. Na podstawie zdjęć mikroskopowych oceniono różne parametry geometryczne (m.in. średnicę Fereta, obwód, powierzchnię przekroju poprzecznego, krągłość, współczynnik kształtu) 237 cząstek, a pomiary spektroskopowe pozwoliły na określenie składu pierwiastkowego tych cząstek. Statystyczną ocenę otrzymanych wyników wykonano metodami analizy głównych składowych i metodami analizy zmiennych złożonych. Stwierdzono istnienie pewnych zależności pomiędzy parametrami geometrycznymi a zawartością pierwiastków chemicznych w cząstkach. Badania te wykazały również, że filtry powietrza z włókna szklanego mogą być z łatwością ponownie wykorzystane do uzyskania dodatkowych informacji o cząstkach zawieszonych w powietrzu w różnych miejscach w dowolnym czasie. Charakter cząsteczek może również dostarczyć informacji o możliwym źródle zanieczyszczeń.

16

The Evolution of Microstructure and Magneto-structural Properties of Heat Treated Ni-Mn-Sn-In Heusler Alloys Sintered by Vacuum Hot Pressing

Maziarz W., Wójcik A., Chulist R., Szczerba M. J., Kowalczyk M., Czaja P., Cesari E., Dutkiewicz J.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 2

727--732

EN

In this work, vacuum hot pressed Ni-Mn-Sn-In Heusler alloys with different concentration of In (0, 2 and 4 at.%), were investigated. The magneto-structural behaviour and microstructure dependencies on chemical composition and on heat treatment were examined. It was found that the martensite start transformation temperature increases with growing In content and to a lesser extent with increasing temperature of heat treatment. The high energy X-ray synchrotron radiation results, demonstrated that both chemical composition as well as temperature of heat treatment slightly modified the crystal structures of the studied alloys. Microstructural investigation performed by transmission electron microscopy confirmed chemical composition and crystal structure changes in the alloys.

17

Microstructure of Multi-Component Ni35Ti35Ta10Co10Cu10 Alloy

Glowka K., Zubko M., Świec P., Prusik K., Dercz G., Matyja E., Stróż D.

Archives of Metallurgy and Materials

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2019

|

Vol. 64, iss. 2

715--719

EN

A new NiTi-based multi-component Ni35 Ti35 Ta10 Co10 Cu10 (at.%) alloy was obtained by vacuum arc melting. The microstructure of the alloy has been studied using scanning and transmission electron microscopy, backscatter electron diffraction and X-ray diffraction techniques. The performed measurements showed presence of two cubic and one tetragonal phases. Energy dispersive X-ray spectroscopy analysis confirmed that all the observed phases contained all five principal elements.

18

Microstructure Analysis of Equiatomic Multi-Component Ni20Ti20Ta20Co20Cu20 Alloy

Glowka K., Zubko M., Świec P., Prusik K., Dercz G., Stróż D.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 2

785--789

EN

An equiatomic multi-component alloy Ni20Ti20Ta20Co20Cu20 (at.%) was obtained using vacuum arc melting. In order to characterize such an alloy, microstructure analysis has been performed using Scanning and Transmission Electron Microscopy, Electron Backscattered Diffraction, X-ray Diffraction and Energy Dispersive X-ray Spectroscopy techniques. Microstructure analysis revealed the presence of one rhombohedral and two cubic phases. Energy Dispersive X-ray Spectroscopy measurements revealed that both observed phases include five chemical elements in the structure. Using Rietveld refinement approach the lattice parameters were refined for the observed phases.

19

Ślady krwi na Całunie Turyńskim : analiza materiałowa od mikro do nanoskali

Jaworski J. S.

Wiadomości Chemiczne

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2018

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[Z] 72, 1-2

61--80

EN

Modern experimental methods of materials science including optical and electron microscopy (SEM, ESEM, HRTEM), X-ray spectroscopy (EDX, WAXS), Raman and FTIR spectroscopy used in investigations of structures of new materials can be also successfully applied for analysis of archeological, cultural heritage and art objects. An interesting example of such analyses are investigations of microscopic fibers and particles taken previously from areas attributed to the blood on the Shroud of Turin. Detailed analyses performed by a number of research groups published in 2015–2017 are reviewed. They confirmed previous hypothesis on blood authenticity and discovered new evidences indicated a violence hidden behind the death. In particular, the presence of old red blood cells was documented by Lucotte [20], of bile pigment biliverdin by Laude and Fanti [28], of iron oxide cores of ferritin bounded to nanoparticles of creatinine by Carlino et al. [31]. The last result is typical for patients with severe polytrauma indicating at the unexpected nonoscopic level a tremendous suffering of the victim wrapped in the Shroud of Turin. Bigger particles of mineral pigments: ochre (iron oxide) and vermillion (mercury sulfide) were also found but they can be easily distinguished form blood particles using environmental electron microscopy ESEM with the back-scattered electrons detector [24]. The statistical analysis of a sample composition made by Fanti and Zagotto [24] indicated that 90–95% of the observed volume corresponds to the blood and only remainder represents inorganic pigments. Thus, it was proposed [24] that the original human blood on Shroud stains was much later reinforced by red pigments using a color dust without any binder and this hypothesis can easily explain controversies between previous results of different researches.

20

Mikrostruktura i właściwości mechaniczne wielowarstwowych platerów na bazie Al i Ti wytwarzanych z wykorzystaniem energii wybuchu

Paul H., Prażmowski M., Gałka A., Miszczyk M.

Przegląd Spawalnictwa

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2018

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R. 90, nr 4

63--65

PL

W pracy analizowano zmiany mikrostrukturalne oraz formowanie się nowych faz w wielowarstwowych układach platerów zbudowanych na bazie Ti i Al. Wykorzystano techniki mikroskopii optycznej i skaningowej mikroskopii elektronowej, pomiary mikrotwardości, a także próbę zginania w warunkach udarowych. Obserwacje w skali makro pokazały, że w procesie spajania wytworzono 15-warstwowy plater wolny od nieciągłości strukturalnych. Powierzchnie połączenia uległy silnemu odkształceniu i wykazywały mieszany falisto-płaski charakter ze strefami przetopień preferencyjnie lokowanymi na grzbiecie oraz w zawinięciach fal. Zaobserwowano, że silnie pofalowane granice połączenia zawsze formowały się w warstwach położonych w pobliżu ładunku wybuchowego. Analizy w mikro skali udokumentowały występowanie cienkiej warstwy przetopionej o silnie rozdrobnionej strukturze.

EN

Microstructure and phase in the bonding zone of explosively welded Ti/Al multilayer clads were examined by optical microscopy and scanning electron microscopy. The defect-free multilayer composite was successfully formed. The macro-scale observations showed that the interfaces between joined plates presented mixed wavy/flat shape with solidified melt inclusions located preferentially at the crest of each wave and in the wave vortex. It was found that interfaces of wavy character were always formed in layers near the explosive charge and flattened with the increase of the distance from the top surface. The micro-scale analyses observations revealed a presence of very thin reaction layer at the flat parts of the joint plates and nano-grained structure of melted zones.