Wyniki wyszukiwania - BazTech

1

Wpływ spawania wiązką elektronów na mikrostrukturę i właściwości mechaniczne stopów AlMgSi (Cu)

Boczkal Sonia, Płonka Bartłomiej, Hrabia-Wiśnios Joanna, Mitka Monika, Węglowski Marek Stanisław, Śliwiński Piotr, Pogorzelski Paweł, Fiołka Marcin, Fiołka Krzysztof

Welding Technology Review

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2026

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R. 98

3--14

PL

Spawanie wiązką elektronów (EBW- ang. Electron Beam Welding) jest odpowiednim procesem spawania dla wielu gatunków stopów aluminium. W niniejszym artykule omówiono wpływ parametrów technologicznych EBW na właściwości złączy spawanych AlSiMg(Cu). Przeprowadzono analizy SEM i EDS w celu zbadania wpływu pierwiastków stopowych, a także parametrów procesu EBW na właściwości złączy spawanych. Przeprowadzone eksperymenty wykazały, że zastosowanie EB może zapewnić spoiny o wysokiej jakości. Nie zaobserwowano porowatości ani pęknięć. Prędkość spawania 2000 mm/min skutkowała wąską szerokością spoin dla wszystkich stopów. W porównaniu z innymi stopami nastąpiło poważne pogorszenie właściwości mechanicznych z powodu zmiękczenia w strefie wtopienia wynikającego z rozpuszczenia wydzieleń wzmacniających w metalu spoiny i SWC, takie pogorszenie występuje w zakresie AlSiMg(Cu) 81-99% materiału podstawowego. Wyniki wykazały wzrost mikrotwardości w strefie wpływu ciepła (HAZ) dla wszystkich złączy spawanych do 116 HV1 (stop 3B) oraz wytrzymałości dla tego samego stopu do 275 MPa (materiał bazowy 277 MPa). Maksymalna wydajność połączenia wynosi 99%. Jednakże próby gięcia wykazały występowanie pęknięć do 3,5 mm.

EN

For many commonly used aluminium alloys, electron beam welding (EBW) is a very suitable welding process. In this study, the influence of EBW technological parameters on properties of AlSiMg(Cu) welded joints were discussed. SEM and EDS analysis studies were conducted to examine the effects of alloying elements as well as EBW parameters on the properties of welded joints. The conducted experiments revealed that the use of EB can produce welds with high quality. Porosity as well as cracks were not observed. The welding speed of 2000 mm/min have resulted in narrow width of welds for all alloys. In comparison with different alloys has experienced severe deterioration in mechanical properties due to softening in the fusion zone resulting from dissolution of the strengthening precipitates in the weld metal and HAZ, such deterioration is in the range of AlSiMg(Cu) 81-99% of base material. The results have shown that, the microhardness increase in HAZ for all welded joints up to 116 HV1 (alloy 3B), and strength for the same alloy up to 275 MPa (base material 277 MPa). Thus, the max joint efficiency is 99%. However, the bend tests indicated that cracks up 3.5 mm occurred.

2

Wpływ wybranych napełniaczy węglowych na właściwości mechaniczne i odporność chemiczną plastyfikowanego poli(chlorku winylu)

Kropidłowska Paulina, Halicka Klaudia, Irzmańska Emilia, Płocińska Magdalena

Przemysł Chemiczny

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2026

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T. 105, nr 1

65--70

PL

Wytworzono kompozyty PVC z grafenem (G) i/lub nanorurkami węglowymi (CNT) metodą dwuetapowego wytłaczania i scharakteryzowano pod kątem wytrzymałości na rozciąganie i rozdzieranie, a także odporności na degradację chemiczną wywołaną olejem mineralnym IRM 903 i n-heptanem. Wykazano, że grafen i CNT zwiększały wytrzymałość mechaniczną PVC, natomiast dodatek samego grafenu nie poprawił ocenianych właściwości. Stopień degradacji chemicznej zależał od interakcji medium z plastyfikatorem, a także od kompatybilności napełniaczy z matrycą kompozytu. Wyniki potwierdzają różnicujący wpływ nanonapełniaczy węglowych na właściwości użytkowe kompozytów PVC.

EN

PVC composites with graphene (G) and/or carbon nanotubes (CNTs) were produced using a 2-stage extrusion method and characterized for tensile and tear strength, as well as resistance to chem. degradation by IRM 903 mineral oil and n-heptane. It was demonstrated that G and CNTs increased the mech. strength of PVC, while the addition of G alone did not improve the assessed properties. The degree of chem. degradation depended on the interaction of the medium with the plasticizer, as well as the compatibility of the fillers with the composite matrix. The results confirm the differential effect of carbon nanofillers on the performance properties of PVC composites.

3

Czy modyfikatory udarności do PVC można stosować zamiennie? Reologiczne i mechaniczne kryteria oceny modyfikatorów udarności w formulacjach PVC

Kumosiński Marcin, Abramowicz Agnieszka, Kaczorowski Marcin, Pawłowski Sławomir, Spasówka-Kumosińska Ewa

Przemysł Chemiczny

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2026

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T. 105, nr 5

546--552

PL

Przeanalizowano komercyjnie dostępne modyfikatory udarności o różnej budowie, które były wprowadzane do mieszanek PVC w ilości 3,5-6,0 phr. Badania obejmowały analizę momentu plastyfikacji w funkcji czasu (tzw. plastogramów), testy wytłaczalności oraz pomiary udarności metodą Charpy’ego. Otrzymane wyniki wykazały istotne różnice w zachowaniu materiałów z różnymi modyfikatorami udarności w warunkach przetwórstwa oraz w ich odporności na kruche pękanie. Stwierdzono, że modyfikatory udarnościowe nie są bezpośrednio wymienne w mieszankach PVC. Ich skuteczność zależy od struktury chemicznej, kompatybilności fazowej oraz interakcji z pozostałymi składnikami receptury. Zamienność może być rozważana jedynie warunkowo, po przeprowadzeniu kompleksowej analizy reologicznej i mechanicznej.

EN

Comm. available impact modifiers of various compns. were incorporated into PVC blends at levels of 3.5-6.0 phr. The study included anal. of Brabender plastograms, extrusion performance tests, and Charpy impact strength measurements. The obtained results revealed significant differences in material behavior under processing conditions as well as in their resistance to brittle fracture. The impact modifiers were not directly interchangeable in PVC formulations. Their effectiveness depends on chem. structure, phase compatibility, and interactions with other components of the formulation. Interchangeability may be considered only conditionally, after a comprehensive rheol. and mech. evaluation.

4

Effects of ultrasonic-frequency pulse current on arc stability, acoustic signal emission and weld quality in underwater wet multi-layer multi-pass welding with Q345 steel

Li Hongliang, Yang Rui, Hu Junjie, Zhao Rui, Wang Jida, Jin Zeshi, Yu Feng

Polish Maritime Research

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2026

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nr 2

105--121

EN

ITo address limitations of poor arc stability and inadequate weld quality in conventional underwater wet welding for marine structural repairs, this study developed an ultrasonic-frequency pulsed (UFP) assisted underwater wet welding (UFP-UWW) process by coupling a constant-voltage power source with an ultrasonic-frequency pulse current generator. The dynamic features of arc voltage, welding current, and underwater acoustic signal were systematically investigated under varying excitation voltages (10–60 V) and frequencies (20–90 kHz). The microstructure, mechanical performance and corrosion resistance of underwater multi-layer multi-pass welds on Q345 low-alloy steel were evaluated. Results indicated that ultrasonic-frequency pulsed current modulation improved overall arc stiffness and enhanced arc combustion stability. The arc acoustic signal pressure and electrical signals exhibited consistent synchronization with external ultrasonic excitation frequency. The arc acoustic signal pressure amplitude increased with elevating excitation voltage but decreased with increasing frequency. The UFP-UWW process successfully produced defect-free multi-layer multi-pass welds. Ultrasonic-frequency electromagnetic stirring in the pool enhanced thermal convection and mass transfer, which disrupted columnar grain growth and refined the weld microstructure. Compared with conventional UWW, the UFP-UWW weld metal showed a significant improvement in tensile strength (an increase of ~7.4%) and impact toughness (by 22.7%), alongside enhanced corrosion resistance. This study confirmed the applicability of UFP-UWW in multi-layer multi-pass welding of thick plates, providing a reliable technical solution for high-quality marine engineering repairs.

5

Application performance of synthetic fibre ropes in marine towing systems

Zhang He, Zeng Ji, Jin Bowen, Chou Chiate, Dong Hailei, Li Hangyu

Polish Maritime Research

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2026

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nr 2

64--73

EN

A multi-body coupled mathematical model of a tug–barge–rope system is developed to address the absence of comprehensive parameter design theories for synthetic fibre ropes in marine towing systems and the challenges associated with stability regulation under complex sea states. This study systematically examines the effects of three rope lengths (20, 80, and 120 m) and three fibre materials (nylon, polyester, and ultra-high-molecular-weight polyethylene) on the dynamic performance of a towing system. The mechanical coupling relationships between system components are explored by utilising a dynamic control model. Parametric analysis highlighted the mechanical properties, elongation deformation, and stiffness evolution of ropes of varying lengths and materials during towing operations. The results indicate that short ropes demonstrate high strain sensitivity and instantaneous stiffness, which can readily induce overloads in the power system of the tug. Medium-length ropes, benefiting from viscoelastic deformation, facilitate energy dissipation, thereby mitigating tension fluctuations and enhancing motion stability. In contrast, long ropes result in delayed barge responses owing to stiffness attenuation. This study also revealed that different fibre materials offer distinct advantages in terms of force transmission, vibration suppression, and load-bearing capacity. Based on model analysis and a parametric study, optimal selection schemes for synthetic fibre ropes are proposed. The findings provide a theoretical foundation and practical guidance for the performance optimisation and engineering application of synthetic fibre ropes in marine towing systems, contributing significantly to the advancement of ocean engineering.

6

Mechanical and impact behaviour of polyurethane-modified epoxy sandwich composites for UAV structures

Roszowska-Jarosz Martyna, Kostrzewa Marcin

Journal of Sustainable Technologies - Problemy Eksploatacji

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2026

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Vol. 116, no. 1

73--81

EN

Sandwich composite structures are widely used in aerospace applications due to their high stiffness to weight ratio, efficient load transfer, and favourable dynamic response. However, conventional epoxy resins exhibit brittle behaviour and a limited resistance to impact loading, which restricts their use in lightweight structures exposed to dynamic or crash related loads. The aim of this study is to investigate the effect of epoxy resin modified with polyurethane, used as an interlayer binder, on the mechanical and impact performance of sandwich composites intended for unmanned aerial vehicle structures. The composites consisted of aramid fibre-reinforced facesheets and a polyvinyl chloride foam core. The epoxy matrix was modified with 5-10% by weight of polyurethane to form an interpenetrating polymer network, enhancing toughness and energy absorption. Mechanical properties were evaluated using dynamic mechanical analysis, Charpy impact testing, three point bending, and puncture resistance tests. The results demonstrate that polyurethane modification significantly improves impact resistance, damage tolerance, and energy absorption capability. These findings indicate that controlled formation of an interpenetrating polymer network is an effective approach for improving the mechanical performance of sandwich composites used in unmanned aerial vehicle structures.

PL

Konstrukcje kompozytowe typu sandwich znajdują szerokie zastosowanie w przemyśle lotniczym i kosmicznym ze względu na wysoki stosunek sztywności do masy, efektywne przenoszenie obciążeń oraz korzystną charakterystykę dynamiczną. Jednak tradycyjne żywice epoksydowe wykazują kruchość i ograniczoną odporność na obciążenia udarowe, co ogranicza ich zastosowanie w lekkich konstrukcjach narażonych na obciążenia dynamiczne lub związane ze zderzeniami. Celem niniejszego badania było zbadanie wpływu żywicy epoksydowej modyfikowanej poliuretanem, stosowanej jako lepiszcze międzywarstwowe, na właściwości mechaniczne i udarowe kompozytów warstwowych przeznaczonych do konstrukcji bezzałogowych statków powietrznych. Analizowane kompozyty składały się z arkuszy wierzchnich wzmocnionych włóknem aramidowym oraz rdzenia ze spienionego polichlorku winylu. Matryca epoksydowa została zmodyfikowana w 5-10% wagowo poliuretanem w celu utworzenia wzajemnie przenikającej sieci polimerowej, zwiększającej wytrzymałość i pochłanianie energii. Właściwości mechaniczne oceniono za pomocą analizy dynamiczno-mechanicznej, próby udarności Charpy’ego, próby zginania trzypunktowego oraz próby odporności na przebicie. Wyniki wykazały, że modyfikacja poliuretanem znacznie poprawia odporność na uderzenia, tolerancję na uszkodzenia oraz zdolność pochłaniania energii. Wyniki te wskazują, że kontrolowane tworzenie sieci polimerowej o wzajemnym przenikaniu jest skutecznym podejściem do poprawy właściwości mechanicznych kompozytów warstwowych stosowanych w konstrukcjach bezzałogowych statków powietrznych.

7

Effect of maleic anhydride on the physicochemical properties of chitosan

Thachangade Ranjana, Lewandowska Katarzyna

Engineering of Biomaterials

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2026

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vol. 29, no. 174

art. no. 24

EN

Chitosan (CS) has been explored in various fields due to its specific properties. Modifications to the glucopyranoside ring of chitosan expand its applicability, improving its existing characteristics and enabling new applications. This study aimed to modify CS with maleic anhydride (MA) at two different temperatures (30°C and 60°C) to investigate the influence of reaction conditions on the properties of the resulting complex. The effect of maleic anhydride on chitosan has been studied using Infrared Spectroscopy (ATR-FTIR), Tensile tests and Contact Angle Measurements. The attachment of MA to the CS backbone has been confirmed by infrared spectroscopy. The mechanical properties and surface free energy values show considerable differences compared to those of pure CS. The results demonstrate that MA incorporation significantly alters the structure–property relationships of CS films. The Young's modulus values were higher, and the contact angle results indicate the improved hydrophilicity of the grafted samples. The physicochemical properties were significantly improved after the incorporation of MA, due to hydrogen bonds formed within the CS matrix. This work establishes a foundational understanding of the basic physicochemical properties of CS–MA complexes and demonstrates how these properties can be tailored through controlled modification toward developing advanced functional systems for biomedical applications such as wound dressing, tissue engineering scaffolds etc.

8

Experimental analysis of the effect of lime addition on the properties of clay bricks (a thermomechanical study)

Zidani Sara, Baira Faycal, Abdelkader Fidjah

Budownictwo i Architektura

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2026

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Vol. 25, no. 2

art. no 26018

EN

The purpose of adding lime to clay bricks is to develop and improve their mechanical, physical, and chemical properties. Lime reduces shrinkage upon drying, thus reducing cracking. Furthermore, it improves the brick's resistance to compression and shape retention, increasing its long-term durability. In this context, tests were conducted on clay bricks with lime contents ranging from 5% to 30% at the University of Djelfa's research facility. A consistent increase in density was observed up to 15% lime. Lime also reduced water retention from 17% to 10%, thereby reducing the brick's vulnerability to moisture. Mechanically, compressive strength increased by 26%. Regarding the thermal aspect, thermal conductivity decreased between 5.71% and 30.28%. The results showed that a 15% lime rate is ideal for achieving a balance between durability and thermal insulation. In the field, lime may be a promising natural and economical option, contributing to reducing carbon emissions and construction costs while improving the maintainability of local assets.

9

Effect of supplementary cementitious materials on the fresh and hardened performance of self-compacting concrete incorporating different aggregate types

Bergad Mohamed, Fodil Dif, Omrane Mahomed

Budownictwo i Architektura

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2026

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Vol. 25, no. 2

art. no 26022

EN

The combined use of recycled coarse aggregates (RCA) and supplementary cementitious materials (SCMs) presents a practical approach to achieving sustainable self-compacting concrete (SCC). This study investigates the combined effects of two type of aggregates: natural coarse aggregates (NCA) and RCA, along with blended binders incorporating silica fume (SF), ground granulated blast-furnace slag (GGBFS), and natural pozzolan (NP). Fourteen SCC mixtures were produced in two parallel series under identical mix-design constraints. Fresh properties were assessed according to EFNARC procedures, while hardened performance was evaluated by compressive and flexural strengths (up to 120 days), ultrasonic pulse velocity (at 28 days), and sorptivity (at 28 days). All mixtures met the requirements for SCC workability and stability. Incorporating RCA was feasible, provided that its higher water demand was adequately compensated for. Among blended systems, the quaternary binder 5% SF, 15% GGBFS, and 5% NP delivered the most balanced performance. It combined stable fresh properties with the highest long-term compressive strength among blended mixes (54.1 MPa with NCA and 48.9 MPa with RCA at 120 days) and reduced sorptivity. Overall, these results demonstrate that optimised multi-SCM binders can mitigate RCA-related drawbacks and facilitate the development of durable SCC with lower cement content

10

Contribution to the reinforcement of cement composites using aggregates from industrial windshield waste

Beladzar Zahra Beladzar, Boukhelkhal Djamila, Guendouz Mohamed, Hadjadj Moussa

Budownictwo i Architektura

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2026

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Vol. 25, no. 1

art. no 26013

EN

The excessive extraction of raw materials for aggregate and cement production for developing sustainable concrete results in significant environmental issues. Automotive windshield waste (WGA) is increasing daily, contributing significantly to landfills due to a rapidly growing population and limited recycling options. This research investigates the use of WGA as a substitute for fine aggregates combined with blast furnace slag (BFS) as a filler to produce a new eco-friendly self-compacting sand concrete (SCSC). For this, eleven SCSC mixtures were prepared at a constant cement and BFS content of 400 kg/m3 and 200 kg/m3, respectively. The water-to-powder ratio was kept constant at 0.44. The superplasticizer-to-cement ratio was selected for each mix to improve the fresh SCSC flowability and homogeneity. The sand was substituted in volume with the WGA at a proportion of 10 to 100% with a step of 10%. The obtained results show the feasibility of producing high-performance SCSC by completely replacing natural sand with WGA, without impairing the concrete’s workability, mechanical, and durability properties. SCSC with 20% WGA substitution was found to be optimum with compressive and flexural strength 80% and 50% higher than the reference concrete, respectively. Furthermore, the use of up to 100% WGA showed high-quality concrete with more than 80 MPa compressive strengths, a significant reduction in water absorption and porosity, a denser microstructure, and a stronger interfacial transition zone (ITZ).

11

A descriptive view of rammed earth performance: bibliometric analysis and systematic literature review

Bilad Ayoub, Ikharrazne Lmokhtar

Budownictwo i Architektura

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2026

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Vol. 25, no. 2

art. no 26032

EN

Rammed earth is a sustainable material with several features that warrant being studied and analysed for safe use as a green building for low-rise buildings due to its minimal CO₂ emissions. The initial section of this paper used bibliometric analysis to review various studies conducted on rammed earth from 2010 to 2024, comprising 960 publications. The subsequent section presents a systematic literature review of 52 publications, focusing on the mechanical properties of rammed earth, such as compressive strength, tensile strength, shear strength, and shear parameters (friction angle and cohesion), as well as thermal performance. The analysis of the outcomes of the previous studies showed that the compressive strength of unstabilised rammed earth ranges from 1 to 2.75 MPa, while stabilised rammed earth exhibits a range of 1.2 to 9.40 MPa, which is adequate for single-story and double-story buildings. The tensile strengths are reported to be between 0.16 and 0.38 MPa for unstabilized rammed earth, and the incorporation of fibres and chemical stabilisers increases them to the range of 0.73 to 1.16 MPa. Furthermore, the seismic behaviour of rammed earth is affected by its shear strength, which is only a small fraction of compressive strength, ranging from 7% to 10%, and is dependent on cohesion and friction angle. This study also developed an expression for predicting the tensile strength of rammed earth based on the percentage of fibres and chemical stabilisers used.

12

Modeling progressive damage accumulation in cortical bone from human ribs using acoustic emission data

García-Vilana S., Sánchez-Molina D., Abdi H., Martinez-Gonzalez E.

Biocybernetics and Biomedical Engineering

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2026

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Vol. 46, iss. 2

278--289

EN

This work investigates how progressive microdamage accumulates in intact human fourth ribs under bending loads and how acoustic emission (AE) signals reflect that deterioration. Twenty-four ex vivo ribs (eighteen under quasi-static (< 0.0004 s −1) and six under dynamic (0.012–0.042 s −1)) were subjected to three-point bending while AE sensors recorded microcrack activity near regions of peak tensile stress. To accommodate large deformations and complex geometry, we applied finite strain theory and described the mechanical response with an orthotropic continuum damage model. Damage growth followed a Weibull distribution, and stiffness degradation closely tracked the damage variable. We then correlated AE event counts with damage progression by fitting an empirical relationship that captures both the gradual accumulation of low-damage events and the abrupt increases in events near failure. Our analyses reveal three key outcomes. First, the Hild-Lemaître quasi-brittle damage model provides an excellent fit to stress-strain data across all strain-rate regimes. Second, cumulative AE counts increase monotonically with internal damage, confirming AE as a reliable real-time proxy for microcrack evolution. Third, AE-damage curves differ qualitatively with strain rate: quasi-static tests produce strongly convex profiles culminating in a near-vertical asymptote, whereas dynamic tests exhibit an initial concave segment followed by a more linear trend before ultimate failure. Furthermore, it was observed that increasing strain rate elevates both ultimate and damage strains, whereas subject age is associated with reductions in ultimate stress and stiffness. In contrast, BMI exerts only minor effects. Finally, b-value analysis did not yield predictive insight for human cortical bone fracture, unlike in concrete. Together, these findings establish AE monitoring coupled with continuum damage mechanics as a powerful framework for characterizing rate-dependent failure in rib cortical bone, which could inform real-time clinical monitoring during high-risk procedures.

13

Application of artificial intelligence methods to determine the optimal process parameters in resistance projection welding of steel nuts

Karski Szymon, Awtoniuk Michał, Szala Mirosław

Applied Computer Science

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2026

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Vol. 22, no. 1

184--198

EN

The study employed applied computer modelling to identify the optimal process parameters for resistance projection welding using the original procedure. The influence of technological parameters (welding power, welding time, electrode pressure) on the quality of 184 welded joints produced by resistance projection welding of steel nuts and S235JR steel plates was examined using computer modelling methods, specifically a combination of machine learning and an evolutionary algorithm. A tree-based model was used to identify relationships between signals, and a genetic algorithm for multi-criteria optimisation. The prepared joints were then examined to determine the impact of the welding parameters on the microstructure, Vickers hardness, and strength of the welded joints (as assessed by pull-off testing). The superior strength of the projection welding joints was achieved through short welding times and high power. Additionally, limited welding time effectively restricted the heat-affected zone, reducing weld hardness and improving the joint's plasticity. The original modelling process enables energy consumption (welding current) to be minimised while maximising joint strength, which was the main aim of the work. Finally, the set of optimised welding parameters selected by AI was verified through sample welding and strength testing, and this was confirmed through final strength testing experiments.

14

Influence of basic 3D printing parameters on mechanical properties of PLA biopolymer prints by FDM method

Stelmachowicz Adrian, Mazur Jacek, Cwalina Paweł, Obidziński Sławomir, Boszorádová Lucia

Agricultural Engineering

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2026

|

Vol. 30, No. 1

141--161

EN

With the rapid advancement of 3D printing technology and increasing demands for production efficiency, it is essential to verify the impact of key process parameters on the mechanical properties of printed parts. Optimizing print speed, temperature, and path orientation is critical to ensuring the repeatability and durability of manufactured components, especially in engineering and industrial applications. Poly-actide (PLA) is a plant-based polymer that is one of the most popular materials used in 3D printing with FDM/FFF technology. The article presents the results of a study on the mechanical properties, specifically tensile strength and bending strength, of specimens manufactured using a Creality K2 Plus 3D printer with PLA. The tests were conducted in accordance with ISO 527-2 for tensile testing and ISO 178 for bending testing on a Stable Micro Systems TA-XT plus Texture Analyser. The filament for printing was extruded on an Artme3D MK3S filament extruder to a diameter of 1.75 mm. The specimens were printed in combinations involving changes in the three crucial printing parameters: temperature (190°C, 200°C, 210°C), printing speed (100 mm‧s-1, 150 mm‧s-1, 200 mm‧s-1) and the layer angle (15°, 30°, 45°, 90°). The study showed that both tensile strength and bending strength are most affected by temperature. Moreover, the optimal printing parameters for the specimens were determined for tensile strength (T=210°C, V=150 mm‧s-1, R=0°) and bending strength (T=200°C, V=200 mm‧s-1, R=0°).

PL

Wraz z dynamicznym rozwojem technologii druku 3D oraz rosnącymi wymaganiami dotyczącymi efektywności produkcji konieczna jest weryfikacja wpływu kluczowych parametrów procesu na właściwości mechaniczne drukowanych elementów. Optymalizacja prędkości druku, temperatury oraz orientacji ścieżki jest niezbędna do zapewnienia powtarzalności i trwałości wytwarzanych komponentów, szczególnie w zastosowaniach inżynierskich i przemysłowych. Polilaktyd (PLA) jest polimerem pochodzenia roślinnego i jednym z najpopularniejszych materiałów stosowanych w druku 3D w technologii FDM/FFF. W artykule przedstawiono wyniki badań właściwości mechanicznych, w szczególności wytrzymałości na rozciąganie i wytrzymałości na zginanie, próbek wykonanych z PLA przy użyciu drukarki 3D Creality K2 Plus. Badania przeprowadzono zgodnie z normą ISO 527-2 dla próby rozciągania oraz normą ISO 178 dla próby zginania, z wykorzystaniem analizatora tekstury Stable Micro Systems TA-XT plus. Filament do druku wytłoczono za pomocą wytłaczarki filamentu Artme3D MK3S do średnicy 1,75 mm. Próbki drukowano w kombinacjach obejmujących zmiany trzech kluczowych parametrów druku: temperatury (190°C, 200°C, 210°C), prędkości druku (100 mm‧s-1, 150 mm‧s-1, 200 mm‧s-1) oraz kąta ułożenia warstw (15°, 30°, 45°, 90°). Badania wykazały, że zarówno wytrzymałość na rozciąganie, jak i wytrzymałość na zginanie są w największym stopniu zależne od temperatury. Ponadto określono optymalne parametry druku próbek dla wytrzymałości na rozciąganie (T = 210°C, V = 150 mm‧s-1, R = 0°) oraz wytrzymałości na zginanie (T = 200°C, V = 200 mm‧s-1, R = 0°).

15

Wire arc additive manufacturing of 5356 aluminium alloy: Processes, properties and performance

Mauduit Arnold, Guilmois Lauriane, Pillot Sébastien, Bachelard Nicolas, Lorinet Quentin

Advances in Science and Technology. Research Journal

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2026

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Vol. 20, no. 6

403--421

EN

This study focuses on Wire Arc Additive Manufacturing (WAAM) of 5356 aluminium alloy. An approach combining designs of experiments and artificial neural networks was implemented to identify the optimal parameters for three MIG welding synergies: pulsed MIG, mixed CMT and pulsed MIG, and CMT MIG. The selected optimisation criteria were material health and the visual quality of the samples. The results obtained showed good material integrity for the three configurations studied (in all cases, the porosity rate is below 0.2%). The optimised samples were then subjected to mechanical and microstructural characterisation. The hardness measurements revealed a good level of homogeneity across the wall section and between the different configurations, both in the as-manufactured state and after annealing treatment (1.5 hours at 350 °C). The as built mechanical properties are consistent with the hardness values, with a tensile strength ranging between 250 MPa and 270  MPa. Slight anisotropy is observed between the building direction and the longitudinal direction of the test specimens (a difference of 2% to 4% in Rm and Rp0.2). The microstructural analysis of the three configurations revealed similar structures, characterised by columnar grains in the core structure of the beads and fine-grained interfacial zones, contrasting with the structures resulting from conventional welding. This difference is a consequence of an increased concentration of constituents, dispersoids and precipitates in the fine-grained zones, promoting abundant nucleation and selective grain growth. The phases were identified by Energy Dispersive Spectroscopy (EDS). Lastly, a correlation between the microstructure and the mechanical properties was established, highlighting a good match between both aspects.

16

Sustainable hybrid composites for wind turbine blades: Mechanical and environmental perspectives

Bryll Katarzyna, Abramovich Alina, Rogala Michał, Drzewieniecki Jan, Gawdzińska Katarzyna, Uriasz Janusz

Advances in Science and Technology. Research Journal

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2026

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Vol. 20, no. 8

360--372

EN

This study presents the results of an investigation into hybrid polymer composites with an epoxy matrix reinforced with glass and jute fibres, evaluated for potential application in wind turbine blades. The objective of the study was to combine the high mechanical strength of glass fibres with the flexibility and environmental advantages of natural fibres. Three types of laminated composites were fabricated: a glass fibre–reinforced composite, a natural fibre–reinforced composite (jute), and a hybrid laminate with a glass–jute–glass stacking sequence. Mechanical testing was conducted in accordance with ISO 527-4 and ISO 148-1 standards. The results indicated that the glass fibre composite exhibited the highest tensile strength (390 MPa). Jute fibre composite demonstrated the greatest elongation at break (4.1%), although with lower tensile strength (198 MPa). Hybrid laminate demonstrated intermediate mechanical properties, achieving a tensile strength of 240 MPa, an elongation at break of 3.4%, and an impact strength of 9.6 J/cm². The results indicate that hybridization of the reinforcing materials improves energy dissipation and delays the onset of failure, thereby enhancing resistance to dynamic load. These findings suggest that hybrid glass–jute composites may be a promising material solution for blades of small wind turbines, combining mechanical performance with improved environmental sustainability.

17

Study of the mechanical properties of C45 steel with a ferrite–pearlite microstructure

Sąsiadek Michał, Woźniak Waldemar, Melichar Martin, Jachowicz Tomasz, Dzuro Timon

Advances in Science and Technology. Research Journal

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2026

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Vol. 20, no. 8

443--450

EN

This paper presents the results of investigations of C45 steel with a ferrite-pearlite microstructure obtained by austenitizing at 850°C, accelerated cooling in compressed air, and subsequent subcritical heat treatment below Ac₁. The applied route is therefore described as accelerated air cooling followed by subcritical holding, and not as classical quenching and tempering of martensite. The specimens were held at 500, 550, 600, 650, and 700°C for 15 min, 1 h, 3 h, 9 h, and 23 h. Tensile testing was used to determine the yield strength Re, ultimate tensile strength Rm, and elongation A, while Vickers microhardness HV0.5 and SEM observations were used to characterize the response of the material. The results showed a monotonic decrease in Re, Rm, and HV0.5 with increasing subcritical heat-treatment temperature and holding time, whereas elongation generally increased, although with local non-monotonic variations. The observed trends are interpreted as consistent with softening processes in a ferrite-pearlite structure; however, because the metallographic evidence is qualitative, the mechanistic interpretation is formulated cautiously. The presented data may support the selection of subcritical heat-treatment parameters for C45 steel when specified tensile properties and hardness are required.

18

Microstructural evolution and fracture behavior of Al2O3-Cu composites sintered without pressure

Piotrkiewicz Paulina, Zygmuntowicz Justyna, Wachowski Marcin, Szachogłuchowicz Ireneusz, Kaszuwara Waldemar

Advances in Science and Technology. Research Journal

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2026

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Vol. 20, no. 8

38--52

EN

Al2O3-Cu composites offer a promising combination of high hardness, thermal stability, and electrical conductivity. In this study, Al2O3-Cu composites containing 2.5 vol.% Cu were produced by uniaxial pressing at 100 MPa, followed by free sintering in a reducing atmosphere (95% Ar/5 % H₂). Sintering was performed at 1200 °C, 1250 °C, 1300 °C, and 1400 °C for 2 h to evaluate the influence of temperature on densification, microstructure, and mechanical properties. Phase analysis confirmed the presence of only corundum Al2O3 and metallic Cu, independent of sintering temperature. Relative density increased strongly with temperature, from 78.65% at 1200 °C to 96.99% at 1400 °C. Microstructural observations revealed significant copper migration at 1400 °C, leading to irregular Cu agglomerates, local depletion of the metallic phase, and the encapsulation of Al2O3 grains through non-wetting liquid-phase sintering. The composites sintered at 1400 °C exhibited an average hardness of 13.6 ± 1.5 GPa and an indentation fracture toughness KIC of 4.94 ± 0.85 MPa·m0.5. Fracture behavior was dominated by intergranular cracking and crack deflection at weak Al2O3-Cu interfaces. The results demonstrate that although high densification can be achieved without external pressure, uncontrolled copper migration remains a key limitation of pressureless sintering in Al2O3-Cu composites.

19

Microstructural and mechanical characterisation of AA8011 aluminium alloy after tungsten inert gas welding under variable current parameters

Dianto Wahyu, Wahyudianto Fx. Arif, Suprihanto Agus, Rusman Rusman, Patayang Mika

Advances in Science and Technology. Research Journal

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2026

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Vol. 20, no. 5

185--201

EN

AA8011 aluminium alloy is widely used in automotive radiator applications due to its good corrosion resistance, adequate strength, and excellent thermal conductivity. However, its mechanical performance after welding is strongly influenced by the thermal cycle and the heat input during TIG welding. This study investigates the effect of welding current variations (115 A, 120 A, and 125 A) on the post-weld mechanical properties and microstructural evolution of AA8011 alloy. Tensile testing, Vickers microhardness mapping, macro-microstructural observations, and weld-bead geometry evaluation were performed in accordance with ASTM and AWS standards. Results show that welding current significantly affects grain morphology, hardness distribution, and tensile performance. The optimum mechanical response was obtained at 120 A. The novelty of this work lies in providing a comprehensive mechanical–microstructural characterisation of TIG-welded AA8011 alloy, thereby contributing scientific insights toward the optimisation of welding parameters for lightweight radiator components.

20

Development of a Johnson-Cook constitutive model for 316L stainless steel manufactured by wire laser metal deposition

Kiciński Radosław

Advances in Science and Technology. Research Journal

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2026

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Vol. 20, no. 2

470--479

EN

Additive manufacturing (AM) of metals is increasingly used in engineering applications; however, the anisotropy of mechanical properties caused by the layer-by-layer deposition process poses challenges for constitutive modelling. This study focuses on 316L stainless steel produced by Wire Laser Metal Deposition (WLMD) and aims to develop a Johnson–Cook (J–C) constitutive model suitable for numerical simulations of this material. Tensile tests were performed on specimens printed in four build orientations (0°, 45°, 90°, and cross-directional XX), and the engineering stress–strain curves were converted into true stress–strain data. Young’s modulus, yield strength (Re₀.₂), ultimate tensile strength (UTS), and strain at UTS were determined for each orientation. The results demonstrated pronounced anisotropy: UTS ranged from ~610 MPa (90°) to ~660 MPa (0°), while total elongation varied between 28% and 37%, depending on the build direction. Based on the true stress–strain data, simplified J–C parameters (A, B, n) were identified for each orientation, achieving a high quality of fit (R² > 0.97). The findings confirm that build orientation significantly influences the mechanical response of WLMD-processed 316L, and that direction-dependent J–C parameters are necessary for reliable finite element (FE) simulations. The proposed model provides a foundation for more advanced constitutive descriptions, including strain-rate and temperature effects.