Wyniki wyszukiwania - BazTech

1

Physical properties of masking coating systems used in military technology

Michalski Marek, Radek Norbert

Zeszyty Naukowe Politechniki Morskiej w Szczecinie

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2025

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nr 82 (154)

69--79

EN

This paper presents the results of experimental tests on coating systems for military applications. The evaluation of properties is performed based on measurements of thickness, gloss, hardness, and surface roughness. The spectral characteristics of the tested systems and color parameters are presented. The tests are conducted for two-layer masking coating systems made in three variants: coating system (SP1), coating system modified with carbon nanotubes (SP2), and coating system modified with glass microspheres (SP3). Analysis of the obtained results reveals that these coating systems exhibit similar thickness, gloss, and spectral characteristics. The SP2 system is characterized by lower hardness, while the SP2 and SP3 systems have higher roughness.

2

Insight into Abrasive Wear of X153CrMoV12 Tool Steel Microalloyed with Varied Niobium Content

Leśniewski Tadeusz, Lachowicz Marzena, Hawryluk Marek, Marzec Jan

Tribologia

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2025

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nr 1

17--28

EN

The article analyses the influence of the addition of niobium on the microstructure, hardness, and wear of X153CrMoV12 cold work tool steel. Steels containing 0.06 wt.% and 0.20 wt.% niobium are characterized using light and scanning electron microscopy methods, hardness measurements and tribological tests. To test the abrasion resistance of selected materials, the authors use the T-07 test stand. The behavior of steel under tribological influences is assessed using scanning electron microscopy. The results show that the abrasive particles have an obvious effect on the loss of steel abrasive mass, but the niobium content determines the relative wear resistance. Steel with a niobium content of 0.20 wt.% is characterized by higher hardness, which ultimately results in higher abrasion resistance. This effect is associated with the presence of niobium carbide precipitates in the steel.

PL

Oceniono wpływ dodatku niobu na mikrostrukturę, twardość i zużycie stali narzędziowej do pracy na zimno gatunku X153CrMoV12. Scharakteryzowano stale zawierające odpowiednio 0,06% wag. oraz 0,20% wag. niobu z wykorzystaniem metod mikroskopii świetlnej, elektronowej skaningowej, pomiarów twardości oraz badań tribologicznych. Badanie odporności na ścieranie wybranych materiałów prowadzono na stanowisku badawczym T-07. Zachowanie stali w warunkach oddziaływań tribologicznych oceniono z wykorzystaniem elektronowej mikroskopii skaningowej. Wyniki pokazały, że cząstki ścierne miały oczywisty wpływ na utratę masy ściernej stali, ale zawartość niobu decydowała o względnej odporności na zużycie. Stal o zawartości niobu 0,20% wag. charakteryzowała się wyższą twardością, co przełożyło się ostatecznie na wyższą odporność na ścieranie. Efekt ten powiązano z obecnością w stali wydzieleń węglików niobu.

3

Improving the mechanical and thermal properties of polyurea by adding copper(ιι) oxide nanoparticles

Saeed Jilan Khalid Mohammed, Sulyman Ebtahag Z., Al-Ahmady Kossay K.

Ochrona przed Korozją

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2025

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nr 7

206--214

EN

Composites consisting of polyurea (PUA) as a matrix material, reinforced with the addition of copper oxide nanoparticles (CuONPs) used in various mass ratios (0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% and 10%) were tested. The resulting composites were examined for their mechanical (hardness, tensile strength, compressive strength), thermal (thermal conductivity, thermogravimetric analysis) and structural (FTIR) properties. The tests showed that reinforcing polyurea with copper oxide nanoparticles improved the mechanical properties (hardness and elastic modulus), while compressive strength decreased by 77% at a weight percentage of 6%, and the best result was obtained at a weight percentage of 1%. Heat treatment also affected the mechanical properties; for example, hardness increased at 7°C and 80°C. Thermal conductivity increased by 57% with the addition of the reinforcement material at room temperature and further increased during heat treatment at 7°C and 80°C. Thermal analysis showed slight changes in the curves, resulting in an improvement in the resistance of the matrix to thermal decomposition. The infrared spectrum showed that the nanoparticles bands overlapped with the matrix. Scanning electron microscopy (SEM) characterization revealed the presence of bonding between the copper nanoparticles (CuONPs) and the polyurea (PUA) matrix.

PL

Przeprowadzono badania kompozytów składających się z polimocznika (PUA) jako materiału matrycowego, wzmocnionego dodatkiem nanocząstek tlenku miedzi (CuONPs) stosowanego w różnych proporcjach masowych (0,5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% i 10%). Otrzymane kompozyty badano pod kątem ich właściwości mechanicznych (twardość, wytrzymałość na rozciąganie, wytrzymałość na ściskanie), termicznych (przewodność cieplna, analiza termograwimetryczna) i strukturalnych (FTIR). Badania wykazały, że wzmocnienie polimocznika nanocząsteczkami tlenku miedzi poprawiło właściwości mechaniczne (twardość i moduł sprężystości), natomiast wytrzymałość na ściskanie spadła o 77% przy udziale masowym tlenku miedzi 6%, a najlepszy wynik uzyskano dla kompozytów zawierających 1% tlenku miedzi. Obróbka cieplna również wpłynęła na właściwości mechaniczne, twardość wzrosła w temp. 7°C i 80°C. Przewodność cieplna wzrosła o 57% po dodaniu materiału wzmacniającego w temperaturze pokojowej i dalej wzrosła podczas obróbki cieplnej w temp. 7°C i 80°C. Analiza termiczna wykazała niewielkie zmiany krzywych, wynikające z poprawy odporności matrycy na rozkład termiczny. Widmo kompozytu w podczerwieni wykazało, obecność dodatkowego pasma wskazującego na obecność nanomateriału Cu-O i podwójnego pasma pochodzącego od grupy C=O co wskazuje na interakcję między nanocząstkami CuO a grupą C=O matrycy. Charakterystyka metodą elektronowej mikroskopii skaningowej (SEM) ujawniła obecność wiązania między nanocząsteczkami miedzi (CuONP) a matrycą polimocznikową (PUA).

4

Characterisation of the microstructure, thermophysical, and mechanical properties of the ti3alc2-tic composite

Łęczycki Krzysztof, Starczewski Maciej, Panas Andrzej, Sałaciński Michał, Krupińska Anna

Journal of KONBiN

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2025

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Vol. 55, iss.2

97--109

EN

This study focuses on a complex complementary investigation of the properties of the composite structure with a Ti3AlC2 MAX phase matrix and dispersive titanium carbide particle filling. The paper presents the results of microstructure studies, thermophysical and mechanical properties of the Ti3AlC2-TiC composite obtained by the SPS (spark plasma sintering) method.. Microstructural observations, including the distribution of both phases of the composite, were carried out using Scanning Electron Microscopy (SEM) combined with Energy-Dispersive X-ray Spectroscopy (EDS). As part of the thermophysical properties analysis, the temperature-dependent thermal diffusivity was determined using the Laser Flash Analysis (LFA) method, along with specific heat capacity measured by LFA using a reference sample, and linear thermal expansion. Based on the parameters and density of the composite (determined from geometric and weight measurements), its thermal conductivity was calculated, accounting for its temperature dependence. The presented material characterisation was supplemented with the results of Dynamic Mechanical Analysis (DMA), performed in a three-point bending mode instrument operation on a free-standing sample, as well as hardness measurements using the Vickers method. The obtained data were analysed, and the results were used both for ongoing calculations of interdependent parameters and to verify the correctness of the acquired data.

PL

Praca dotyczy kompleksowych komplementarnych badań właściwości struktury kompozytu z osnową fazy MAX Ti3AlC2 i dyspersyjnym wypełnieniem cząstkami węglika tytanu. W referacie przedstawiono wyniki badań mikrostruktury, właściwości cieplnofizycznych oraz mechanicznych kompozytu Ti3AlC2-TiC uzyskanego metodą SPS (spark plasma sintering). Obserwacje mikrostruktury z uwzględnieniem rozmieszczenia obydwu faz kompozytu przeprowadzono z wykorzystaniem metod skaningowej mikroskopii elektronowej (SEM) z zastosowaniem spektroskopii dyspersji energii (EDS). W ramach badań właściwości cieplnofizycznych określono zależności temperaturowe dyfuzyjności cieplnej metodą wymuszenia laserowego (LFA), ciepła właściwego metodą LFA z wykorzystaniem pomiarów wzorca oraz liniowej rozszerzalności cieplnej. Na podstawie uzyskanych parametrów oraz gęstości kompozytu wyznaczonej metodą wypornościową obliczono jego przewodność cieplną z uwzględnieniem jej zależności od temperatury. Przedstawioną charakterystykę materiału rozszerzono o wyniki pomiarów dynamicznej analizy (termo)mechanicznej (DMA), które zrealizowano w trybie trójpunktowego zginania próbki swobodnej oraz o pomiary twardości metodą Vickersa. Uzyskane dane były poddane analizie, której wyniki wykorzystano zarówno do bieżącego przeliczania wartości zależnych od siebie parametrów, jak i do sprawdzenia poprawności uzyskiwanych danych.

5

High-entropy alcocufeni matrix composites reinforced with tungsten carbide

Żakowski Michał, Cieślak Grzegorz, Oleszak Dariusz

Composites Theory and Practice

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2025

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R. 25 nr 2

75-81

EN

In the present study, metallic-ceramic composites were fabricated, with an equimolar high-entropy AlCoCuFeNi alloy as the matrix, and tungsten carbide WC (5 and 10% by volume) as the reinforcing phase. Induction melting and arc melting techniques were used for composite preparation. The metallic matrix of the composite exhibited a two- phase structure consisting of FCC and BCC solid solutions. Microscopic investigations revealed a dendritic micro- structure of the matrix, in which the WC particles were distributed non-homogeneously, regardless of the melting method. Strong precipitation of the chemical composition in the matrix was observed, with interdendritic regions enriched in copper and dendrites enriched in aluminium, nickel and iron. Additionally, besides WC particles, two types of precipitates, with various morphology, were observed in the matrix. The addition of tungsten carbide particles re- sulted in an increase in the composite hardness from approximately 273 HV for the high-entropy alloy to as high as 332 HV for the composite. The appearance of the precipitates can be attributed to the chemical reaction between the liquid matrix and WC, resulting in the formation of complex carbides.

6

Optimizing the impact strength and hardness of the liquid crystal display printed parts using artificial neural network

Abdulrazaq Mustafa Mohammed, Najm Vian N., Ahmed Athraa Mohammed S.

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 8

373--383

EN

Vat photopolymerization (VPP) is an effective additive manufacturing (AM) process known for its high dimensional accuracy and excellent surface finish. The combination of visible light with the use of LCD screens for 3D printing, allows for a faster, more efficient and economical manufacturing process. Despite these benefits, fabricating the end-use products still has some limitations related to the strength of the fabricated parts. For this purpose, the present paper provides a methodology to predict and optimize three critical process variables in AM, namely: layer height, build orientation, post-curing time. A neural-network model was developed for predicting the impact strength and hardness and optimizing the printing variables for highest responses. From the experiments using full-factorial design, it was revealed that improved parts strength and hardness are obtained at lower layer height, flat orientation, and moderate post-curing time. Based on the ANOVA analysis of, the most effective variable on the impact strength was post-curing time with (41.8%), while the orientation was higher contribution than the rest on the parts hardness with (47.5%). Comparisons between the experimental and the predicted values were illustrated. The mean error between experimental and neural network model was (1.13%) for impact strength and (0.82%) for hardness strength with correlation coefficient equal to 0.988 and 0.982 for the two responses respectively. The current proposed study demonstrates good agreement between the predicted model values and the experiments outcomes of impact strength and parts hardness.

7

Mechanical properties analysis of burnished brass

Al-mahasne Mayas Mohammad

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 8

423--433

EN

Brass alloy consists of copper and zinc. It is used as an industrial material because of its hardness and workability, high corrosion resistance, magnetism and good forging ability. This paper evaluates the mechanical properties of brass alloy subjected to cold working which caused plastic straining of the surface of brass specimen resulting from burnishing forces. Forces have a significant role in a burnished surface of brass sample which squeeze it against the samples making plastic twisting of the specimen surface. Burnishing results under variable forces are investigated. The best results of surface roughness have the forces rate of more than 100 N. with a feed rate (0.07 mm/rev).

8

DOCOL 1100M welding in the construction of electric means of transport

Szczucka-Lasota Bożena, Gołombek Klaudiusz, Węgrzyn Tomasz, Łazarz Bogusław, Lukaszkowicz Krzysztof, Pereira Silva Abilio, Antczak-Jarząbska Romana

Transport Problems

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2024

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T. 19, z. 2

219--228

EN

Advanced high-strength steels are important for the automotive sector. Metal active gas (MAG) is the most popular method for joining grades of steel. The goal of the paper is to analyze the mechanical properties of the MAG welding joint made of high-strength DOCOL 1100M intended for the construction of electric vehicles. The manuscript shows a basic understanding of the properties of DOCOL joints. This type of material is characterized by a martensitic microstructure, which makes it difficult to make a proper joint. The tensile strength, metallographic structure, and type of non-metallic inclusions were analyzed as a function of the oxygen amount in the protective gas mixture. Investigations of oxide non-metallic inclusions were carried out using scanning electron microscopy. This article attempts to obtain high joint strength of the electric vehicle structure by controlling the average size of non-metallic inclusions in the weld, which is influenced by shielding gas in the MAG welding process. The solution has application potential for the automotive industry, especially for electric vehicles.

9

Ocena wpływu fotopolimeryzacji na mikrotwardość kompozytów typu bulk-fill

Pieniak Daniel, Niewczas Agata M., Gil Leszek, Krzysiak Zbigniew

Przemysł Chemiczny

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2024

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T. 103, nr 3

391--394

PL

Przedstawiono wyniki badań mikrotwardości trzech powszechnie stosowanych kompozytów handlowych typu bulk-fill. Celem pracy była ocena wpływu fotopolimeryzacji próbek o grubości nominalnej 2 mm na wytrzymałość stykową powierzchni. Wytrzymałość stykową oceniano w testach mikrotwardości metodą Vickersa. Badano mikrotwardość na powierzchniach naświetlanej (LC) i nienaświetlanej (NLC) lampą stomatologiczną UV. W badaniach wykorzystano lampę z funkcją soft start. Próbki przed badaniem mikrotwardości kondycjonowano w sztucznej ślinie w temp. 36,7°C. Wyniki badań poddano analizie statystycznej. W przypadku jednego kompozytu B-F wykazano brak istotnych różnic mikrotwardości na powierzchni LC i NLC. Mikrotwardość kompozytów TPF i EU na powierzchni NLC była istotnie większa niż na LC. Ponadto różnica mikrotwardości powierzchni LC i NLC kompozytu EU była największa.

EN

Samples of 3 com. bulk-fill dental composites were tested for Vickers microhardness to det. the effect of photopolymn. of samples with a nominal thickness of 2 mm on the surface contact strength. Microhardness was tested on surfaces exposed (LC) and not exposed (NLC) to a UV dental lamp. Before testing the microhardness, the samples were conditioned in artificial saliva at 36.7°C. The research results were statistical analyzed. In 2 of 3 tested composites, significantly higher microhardness was found on the NLC surface than on the LC surface.

10

Surface layer performance of low-cost 3D-printed sliding components in metal-polymer friction

Pieniak Daniel, Michalczewski Remigiusz, Firlej Marcel, Krzysiak Zbigniew, Przystupa Krzysztof, Kalbarczyk Marek, Osuch-Słomka Edyta, Snarski-Adamski Andrzej, Gil Leszek, Seykorova Maria

Production Engineering Archives

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2024

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Vol. 30, Iss. 3

361--376

EN

The paper presents the results of contact strength and tribological property tests of spare parts made of a popular resin using a 3D DLP printing technology. Two printer models by the same manufacturer were used in the study. The post-processing technique, which shapes the final functional properties, was diversified. Surface performance properties were compared, i.e. Shore hardness, indentation hardness, Martens hardness, elastic modulus, and parameters related to surface creep and relaxation. Tribological durability in rotary motion and tribological wear in reciprocating linear motion were also evaluated using micro- and nanotribometers. This was followed by surface analyses of the friction track of the analysed materials using microscopic methods: a scanning electron microscope, a WLI interferometric microscope, and an optical microscope. The results were statistically processed and the relationship between the parameters determined in the indentation test was determined.

11

Mechanical Properties of Material Extrusion Printed Samples Made of PLA After Treatment in an Acetone Bath

Szczygieł Paweł, Kowalska Natalia

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

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2024

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Vol. 15, Nr 2 (56)

71--82

EN

This paper presents a study of the effect of chemical treatment using pure acetone on strength specimens made from PLA polylactide produced by 3D FDM/FFF printing technology. The strength specimens were designed in accordance with the ISO 527 standard. The chemical treatment was carried out using baths at different time intervals. The hardness of the samples was measured, and a tensile test was performed. The results show that with prolonged contact with acetone, the hardness of the material decreases by approximately 45% compared to untreated samples. When analysing the tensile tests, it was noted that the tensile strength decreases with longer chemical bath time. At the same time, the material becomes more ductile, resulting in a high elongation at break in tension of up to 40% relative to untreated samples.

PL

W artykule przedstawiono badanie wpływu obróbki chemicznej przy użyciu czystego acetonu na wytrzymałość próbek wykonanych z polilaktydu PLA w technologii druku 3D FDM/FFF. Próbki wytrzymałościowe zostały zaprojektowane zgodnie z normą ISO 527. Obróbkę chemiczną w roztworze acetonu przeprowadzono w różnych odstępach czasu. Zmierzono twardość próbek i przeprowadzono statyczną próbę rozciągania. Wyniki wskazują, że przy dłuższym kontakcie z acetonem twardość materiału spada o około 45% w porównaniu z próbkami niepoddanymi obróbce. Analizując testy rozciągania, zauważono, że wytrzymałość na rozciąganie zmniejsza się wraz z wydłużeniem czasu trwania kąpieli chemicznej. Jednocześnie materiał staje się bardziej plastyczny, co powoduje, że wydłużenie przy zerwaniu jest o 40% większe w porównaniu do próbek niepoddanych obróbce chemicznej.

12

The high-hardness ceramic glazes based on basalt from Bali Province for ceramic body coatings

Sundari Komang Nelly, Subari, Birawidha David C, Prasetia Hendra, Mudra I Wayan, Hendronursito Yusup

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 3

art. no. 190121

EN

The ceramic glaze method is not only done to add color aesthetics but also to increase the hardness of the glaze. Basalt is one of the raw materials developed as a ceramic glaze material because it is cheap, easy to find, and has good characteristics. This research aims to determine glaze characteristics by varying the concentration of basalt rocks from the Ababi area, Karangasem Regency, Bali Province. The experiment used basalt at 45%-61%, Feldspar 27%-37%, Kaolin 3%-8%, and ZnO 7%-10% as raw materials for glaze, not frit glaze. Heating the glaze material layer at 1,250 °C for 3 hrs. The product characteristics of glaze ceramics include chemical composition, crystal phase, microhardness, porosity, density, thermal expansion coefficient, and surface morphology. Basalt from Bali is characterized by its high Fe2O3 content, reaching 20.07 wt%. Compared to basalt in generally, it has a different impact on the physical and mechanical characteristics of the ceramic glaze produced. Based on the observation of ceramic glaze products, the glaze composition with 56% basalt, 32% feldspar, 5% kaolin, and 7% ZnO showed the best coating, with a yellowish-brown color and an average thickness of 79.82μm. The hardness value of the glaze layer is 6.5 GPa, exceeding the standard hardness value of glazes on the market. Glazed ceramics contain the minerals Gahnite (ZnAl2O4) and Coesite (SiO2), which can increase the hardness of the glaze. This research demonstrates the tremendous potential and added value of using basalt from Bali Province as a raw material for glazed ceramics.

13

Improving mechanical and thermal properties of unsaturated polyester resin by adding automotive glass waste

Hemadi Assis Ekhlass K., Al-Ahmady Kossay K., Sulyman Ebtahag Z.

Ochrona przed Korozją

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2024

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nr 10

294--305

EN

The primary goal of this study was to improve a number of mechanical properties of UPE (unsaturated polyester) by using available and cheap particulate fillers, such as reinforcement with powder with a particle size of 75 μm. A composite of UPE with automotive glass waste (as filler materials) was prepared, and some mechanical and thermal properties were studied at certain weight percentages (5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, and 50%). A comparison was made between the polymeric composites before and after the process of reinforcing them with waste automotive glass, and it was found that with a 30% content of these additives they showed good mechanical properties. These additions were made at different temperatures: 8°C, 25°C and 50°C. The results before and after the reinforcement process for polymer composites showed that there was an improvement in the mechanical properties (compressive strength, hardness and impact resistance) with a decrease in the modulus of elasticity (Young’s modulus). When processing was carried out at a temperature of 8°C, a decrease in the values of the mechanical properties (compressive strength, impact strength, modulus of elasticity, thermal conductivity) was observed in varying proportions, with an increase in the values of hardness. Conversely, when the samples were heated to a temperature of 50°C, there was an increase in the values of the above-mentioned properties and a significant decrease in the hardness values. Throughout the research, various measurement techniques were used, including scanning electron microscopy (SEM), infrared spectroscopy (IR) and thermogravimetric analysis (TGA). Their purpose was to monitor the changes that occurred in the polymer as a result of the use of the reinforcing material (automotive glass).

PL

Głównym celem badań było poprawienie właściwości mechanicznych UPE (nienasyconego poliestru) poprzez zastosowanie dostępnych i tanich wypełniaczy cząsteczkowych, na przykład przez wzmocnienie proszkiem o wielkości cząstek wynoszącej 75 μm. Przygotowano kompozyt UPE ze szklanymi odpadami przemysłu motoryzacyjnego (jako materiałem wypełniającym) i zbadano wybrane właściwości mechaniczne i termiczne przy określonych procentach wagowych (5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45% i 50%). Porównano kompozyty polimerowe przed procesem wzmacniania odpadami szklanymi i po nim. Stwierdzono, że przy 30-procentowym udziale tych dodatków wykazywały one dobre właściwości mechaniczne. Dodatki zostały wprowadzone w różnych temperaturach: 8°C, 25°C i 50°C. Analiza wyników przed wzmocnieniem kompozytów polimerowych i po tym procesie wykazała, że nastąpiła poprawa właściwości mechanicznych (wytrzymałości na ściskanie, twardości i udarności) przy spadku modułu sprężystości (modułu Younga). Po przetwarzaniu w temperaturze 8°C odnotowano spadek wartości parametrów mechanicznych (wytrzymałości na ściskanie, udarności, modułu sprężystości, przewodności cieplnej) w różnych proporcjach przy jednoczesnym wzroście twardości. Z kolei po podgrzaniu próbek do temperatury 50°C zwiększyły się wartości wymienionych właściwości i znacznie zmniejszyła twardość. W badaniach wykorzystano różne techniki pomiarowe, w tym skaningową mikroskopię elektronową (SEM), spektroskopię w podczerwieni (IR) i analizę termograwimetryczną (TGA), w celu zweryfikowania zmian zachodzących w polimerze w wyniku zastosowania materiału wzmacniającego (szklanych odpadów przemysłu motoryzacyjnego).

14

Comparative analysis of selected parameters of thin-walled samples produced using FFF/FDM 3D printing technology

Musiałek Mateusz

Mechanik

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2024

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R. 97, nr 12

40--42

EN

The article presents a comparative analysis of specimens produced using FFF/FDM 3D printing technology. The specimens were designed according to ISO 868. The hardness of the specimens was measured, and accuracy as well as the mass of selected colors were measured. The PLA material was chosen due to its wide application and popularity. The dimensional accuracy of the specimens was assessed. The nominal values are considered as a reference for determining the percentage accuracy for each specimens. The data obtained from this study can help to identify the optimal configurations that guide the production of components using filaments through printing.

PL

W artykule przedstawiono analizę porównawczą próbek wyprodukowanych w technologii druku 3D FFF/FDM. Próbki zaprojektowano zgodnie z normą ISO 868. Zmierzono twardość próbek i wykonano pomiary dokładności oraz pomiar masy wybranych kolorów. Materiał PLA został wybrany ze względu na bardzo szerokie zastosowanie i popularność. Oceniono dokładność wymiarową próbek. Wartości nominalne są uważane za odniesienie do określenia procentowej dokładności każdej próbki. Dane uzyskane z tego badania mogą pomóc zidentyfikować optymalne konfiguracje, które determinują produkcję komponentów z użyciem filamentów poprzez drukowanie.

15

Fruit classification by assessing slice hardness based on rgb imaging. case study: apple slices

Falih Bashar S., Gierz Łukasz, Al-Sammarraie Mustafa A.J.

Journal of Applied Mathematics and Computational Mechanics

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2024

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Vol. 23, nr 3

7--18

EN

Correct grading of apple slices can help ensure quality and improve the marketability of the final product, which can impact the overall development of the apple slice industry post-harvest. The study intends to employ the convolutional neural network (CNN) architectures of ResNet-18 and DenseNet-201 and classical machine learning (ML) classifiers such as Wide Neural Networks (WNN), Naive Bayes (NB), and two kernels of support vector machines (SVM) to classify apple slices into different hardness classes based on their RGB values. Our research data showed that the DenseNet-201 features classified by the SVM-Cubic kernel had the highest accuracy and lowest standard deviation (SD) among all the methods we tested, at 89.51 %  1.66 %. This classifier has proved to be the best compared to the others with two features, DenseNet-201 and ResNet-18, along with WNN, NB, and SVM (cubic and linear) kernels.

16

Tests of the Mechanical and Acoustic Parameters of Electric Guitar Bodies

Ryniewicz Andrzej, Pietruch Marcin, Ryniewicz Anna M., Bojko Łukasz

Drewno : prace naukowe, doniesienia, komunikaty

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2024

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Vol. 67, nr 214

Art. no. 194995

EN

The aim of this work was to perform a mechanical and acoustic analysis of electric guitar bodies. Sam ples of ash, oak, walnut, lime tree, and fir were selected for mechanical tests - with constant moisture content, made of latewood, and free from defects. The tests were carried out on a Brinell device to determine the hardness of the wood, and on an MCT3 machine from Anton Paar to determine the microhardness and elastic moduli. The elastic properties of wood are determined by its anisotropy and have different values depending on the direction of force in relation to the fibers. The wood showed the greatest stiffness along the fibers; in the case of forces acting perpendicular to the fibers, the stiffness was much lower. Sound transmission tests of selected acoustic parameters were carried out. They involved measuring and analyzing the frequency and damping of vibrations of guitar bodies using a special vibration sensor. The acoustic parameters of a guitar body experimentally made from walnut were compared with those of a mass-produced Ibanez guitar made of ash wood. Each species of wood has its own characteristic blend of physical properties, such as grain structure, density, weight, and strength, which influence the final tonal power of the guitar. The test results of various wood species indicate significant differences in strength and acoustic-resonance properties, which determine the absorption of vibrations, sound amplification, and sound transmission. The use of a specific wood for a guitar body is dependent on the musician’s artistic vision and the purpose of the instrument.

17

Mechanical behaviour and failure mechanism of resistance spot welded aluminium and copper joint used in the lightweight structures

Fakhri Marwah Sabah, Al-Mukhtar Ahmed, Mahmood Ibtihal A.

Diagnostyka

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2024

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Vol. 25, No. 2

art. no. 2024207

EN

Recently, dissimilar metals have found applications in the process of resistance spot welding (RSW), particularly within the electric vehicle industry. Notably, copper and aluminum have gained significant importance in these sectors due to their advantageous characteristics for the industry requirements. The mechanical behavior of these materials is essential to maintaining structural integrity. The study aims to estimate the mechanical behavior of dissimilar RSW joints and optimize welding parameters for Cu-Al joints. Hence, understanding the joining processes in the electric vehicle industry to design reliable components. Combining different types of materials, such as T2-grade commercially pure copper sheets and aluminum AA1050 with the same thickness of 1 mm has been welded. The determination of optimal welding conditions takes into account material thicknesses and types. Through tensile-shear testing, welding parameters that yield maximal joint strength were identified. Using Minitab 19 software, the Taguchi method helped achieve optimized welding parameters. The hardness, fracture characteristics, and weld strength have been investigated. Hardness measurements were conducted across the nugget thickness and surface, offering insights into potential failure modes. The welding process involves the transition to a liquid state for the aluminum components, resulting in the formation of intermetallic compounds. Consequently, crack initiation was observed within the aluminum segments, leading to a plug-out fracture mechanism. In contrast, copper exhibits superior strength and hardness compared to aluminum, where increased hardness correlates with heightened strength. The discrepancy in hardness, especially the lower values observed on the aluminum side, caused fractures to appear within the heat affected zone (HAZ). Subsequently, this fracture propagated until pull-out failure was realized. The study revealed that dissimilar joining of Cu and Al resulted in an ultimate tensile stress of 26 MPa, while similar joining of copper showcased a strength of 98 MPa. Additionally, the symmetric join in aluminum exhibited a strength of 93 MPa. The maximum tensile shear force is equal to 512 N at a maximum welding current of 14000 A. The pull-out failure mode occurs in the Cu-Al RSW joint. The maximum hardness was noted in the fusion zone (FZ). Relevant literature sources have supported and confirmed these outcomes.

18

Plastic deformation mechanisms in BCC single crystals and equiatomic alloys: Insights from nanoindentation

Dominguez-Gutierrez Francisco Javier, Papanikolaou Stefanos, Bonfanti Silvia, Alava Mikko

Computer Methods in Materials Science

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2024

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Vol. 24, No. 1

37--49

EN

Deformation plasticity mechanisms in alloys and compounds may reveal the material’s capacity towards optimal mechanical properties. We conducted a series of molecular dynamics (MD) simulations to investigate plasticity mechanisms due to nanoindentation in pure tungsten, molybdenum, and vanadium body-centered cubic single crystals, as well as the body-centered cubic, equiatomic, random solid solutions (RSS) of tungsten–molybdenum and tungsten–vanadium alloys. Our analysis focuses on a thorough, side-by-side comparison of dynamic deformation processes, defect nucleation, and evolution, along with corresponding stress–strain curves. We also checked the surface morphology of indented samples through atomic shear strain mapping. As expected, the presence of Mo and V atoms in W matrices introduces lattice strain and distortion, increasing material resistance to deformation and slowing down dislocation mobility of dislocation loops with a Burgers vector of 1/2 〈111〉. Our side-by-side comparison displays a remarkable suppression of the plastic zone size in equiatomic W–V RSS, but not in equiatomic W–Mo RSS alloys, displaying a clear prediction for optimal hardening response of equiatomic W–V RSS alloys. If the small-depth nanoindentation plastic response is indicative of overall mechanical performance, it is possible to conceive a novel MD-based pathway towards material design for mechanical applications in complex, multi-component alloys.

19

Microstructure Characterisation, Hardness, and Corrosion Behaviour of Nickel-Silicon Carbide Electrodeposition Coating with The Influence of Ultrasonic Agitation

Loganathan Agalyah, Kamdi Zakiah, Ainuddin Ainun Rahmahwati, Husin Rosniza, Ibrahim Siti Aida, Salleh Mohd Arif Anuar Mohd

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 3

859--863

EN

This study is about the electrodeposition of Ni-SiC composite coatings at various ultrasonic agitation temperatures (50, 55, and 60°C). The coatings were characterised by a scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). Vickers microhardness test and immersion test were used to determine the hardness and corrosion behaviour of the composite coating respectively. The immersion test was conducted in 0.5M sulphuric acid to analyse the coating corrosion rate. The results demonstrate that increasing the ultrasonic agitation temperature increase the corrosion resistance of the composite coating. Furthermore, the hardness of the Ni-SiC shows higher hardness values at the highest agitation temperature, 60°C. This shows that Ni-SiC composite coating sample S.60 had the best hardness and corrosion behaviour.

20

Comparison of the Properties of Cold Work Tool Steels with the Same Hardness but Different Manufacturing Processes

Tóth László, Fábián Enikő Réka, Pinke Peter, Kovács Tunde Anna, Nabiałek Marcin, Sandu Andrei Victor, Vizureanu Petrica

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 3

809--817

EN

The required important properties of cold work tool steels are hardness, wear resistance, suitable toughness and in many cases corrosion resistance. For cold work tool steels, hardness can be well controlled by heat treatment, but steels of the same hardness do not necessarily have similar wear, corrosion resistance or even toughness. These properties are influenced by the chemical composition of the steels and their manufacturing processes. The study is performed on Böhler K390 PM produced by powder metallurgy (PM) process, Böhler K360 ESR made by electro-slag remelting (ESR) methods and Böhler K110 produced conventionally (C). The specimens were heat treated to obtain the same hardness of 61 HRC. It was made a comparative test of the abrasive wear resistance, corrosion resistance and toughness of the heat-treated cold work tool steel test specimens. The comparative test results show that the Böhler K110 steel has the best corrosion resistance against the 20% acetic acid, and the Böhler K390 PM steel has the best wear resistance and toughness. The goal of the research was to find the optimal cold work tool steel quality for special applications (as a function of wear resistance, corrosion resistance and toughness). The K390 reached the best wear resistance which is two times better than the K360 and about ten times better than the K110. About the corrosion test results, it can be concluded that K110 showed the lowest weight loss after the corrosion test, and the K390 and K360 showed higher weight loss and lower corrosion resistance. Impact energy values from the Charpy impact test were the highest in the case of K390 followed by the K360 and the K110. The results were confirmed by the microscopic analysis.