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1

Effect of Sr and B modification on impact strength and fracture behavior of AlSi9Mg alloy for marine applications

Romankiewicz Remigiusz

Zeszyty Naukowe Politechniki Morskiej w Szczecinie

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2025

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nr 84 (156)

56--67

EN

AlSi9Mg silumins are increasingly used in lightweight ship structures and onboard equipment, where resistance to impact and vibration is crucial. This study evaluates the effect of AlSr10 (0.15 and 0.30% Sr) and AlB4 (0.20% B) additions on the microstructure, impact strength and fracture behavior of the AlSi9Mg alloy. The highest improvement in impact strength—from 4.8 to 11.1 J/cm²—is achieved with 0.30% AlSr10. The lamellar eutectic β(Si) transformed into a fine fibrous morphology, reducing interphase spacing and producing a more tortuous fracture profile, which enhanced dynamic load resistance. While the AlB4 addition shortened α(Al) dendrites, it did not significantly improve impact strength (4.13 J/cm²). The results demonstrate that a properly selected Sr level enables the design of components (e.g., brackets, housings, and guards) for marine environments subjected to impact and vibration. This work provides a basis for future investigations into long-term durability of modified silumins under corrosive marine conditions and combined impact–vibration loads specific to waterborne transport.

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

Insight into the corrosion in non-ferrous alloy heat exchangers

Lachowicz Marzena M., Lachowicz Maciej B.

Ochrona przed Korozją

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2025

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nr 1

2--11

EN

Selected issues relating to the corrosion of non-ferrous heat exchanger components in their operating environment have been presented. With the increasing demand for such equipment, the number of reported corrosion-related failures is steadily increasing, resulting in rising operating costs. This paper introduces the different types of corrosion and defines selected corrosion problems affecting aluminium heat exchanger components. Macroscopic images are shown and the mechanism of corrosion caused by the presence of organic decomposition products on the surface of copper elements is discussed. In relation to copper, an example of corrosion caused by sulphate ions is also presented. The study also includes an example related to the hydrogenation of a titanium heat exchanger plate. The analyses presented in this paper are related to engineering practice and are relevant to the design of thermal energy exchange devices. The possibility of early detection of existing corrosion hazards will also help to prevent potential mechanical failures in heat exchangers.

PL

W pracy przedstawiono wybrane zagadnienia związane z korozją nieżelaznych elementów wymienników ciepła w ich środowisku eksploatacyjnym. Rosnący popyt na te urządzenia powoduje, że ilość odnotowanych awarii wywołanych korozją stale wzrasta, co wiąże się z rosnącymi kosztami ich eksploatacji. W pracy przedstawiono różne typy korozji, a także zdefiniowano wybrane problemy korozyjne dotyczące aluminiowych elementów wymienników ciepła. Pokazano obrazy makroskopowe oraz omówiono mechanizm korozji spowodowanej obecnością produktów rozkładu substancji organicznych na powierzchni elementów miedzianych. W odniesieniu do miedzi przedstawiono również przykład korozji wywołanej jonami siarczanowymi. W ramach badań przedstawiono także przykład związany z nawodorowaniem tytanowej płyty wymiennika ciepła. Przedstawione w pracy analizy związane są z praktyką inżynierską i stanowią istotne znaczenie dla projektowania urządzeń służących do wymiany energii cieplnej. Możliwość wczesnej detekcji istniejących zagrożeń korozyjnych pozwoli również zapobiegać potencjalnym awariom mechanicznym w wymiennikach ciepła.

4

Optimizing δ-ferrite structure to enhance high-temperature elongation in ER308L stainless steel deposited metal

Jiang Cong, Qi Yanchang, Xu Zixin, Yang Guangchang, Ma Chengyong

Materials Science Poland

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2025

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Vol. 43, No. 2

52--62

EN

As the size and weight of crucial equipment in third-generation nuclear power plants increase, the demand for high-temperature plasticity in welds has become more critical. This study examines the effect of varying δ-ferrite content on the high-temperature tensile properties of 308L austenitic stainless steel deposited metal at 350°C. The results reveal that as the δ-ferrite content decreased from 11.6 to 7.4%, the ferrite morphology shifted from continuous lathy and network structures to a discontinuous skeletal form. Correspondingly, 350°C high-temperature elongation increased from 26 to 32%, while tensile strength remained stable across all specimens, exhibiting good strength and plasticity at room temperature. The discontinuous skeletal δ-ferrite (7.4%) suppresses interfacial crack propagation during high-temperature tensile testing, thereby improving the high-temperature ductility.

5

Bonding mechanism between the AlN ceramic matrix and the copper-based metal cladding layer

Wang Song, Lu Hao, Shu Fengyuan, Zhang Xin, Li Guibian

Materials Science Poland

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2025

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Vol. 43, No. 1

42--50

EN

High-temperature brazing and laser cladding methods can form a good metallurgical bond between ceramics and copper cladding. Herein, through these two methods, the preparation of a Cu-based metal cladding layer on the surface of aluminum nitride (AlN) ceramics was carried out. Scanning electron microscopy, X-ray diffraction, energy-dispersive spectroscopy, and other characterization techniques were employed to observe the macroscopic and microscopic morphologies, elemental distribution, and microstructure characteristics of Cu-based metal coatings and transition layers, in order to analyze the interface bonding mechanism. Research has found that the active element titanium (Ti) has a significant promoting effect on the wettability of Cu powder on the surface of ceramics. Metallurgical reactions occur at the interface between ceramics and Cu-based metal coatings. Al and N elements in ceramics react with most of the Ti in the metal coating and Cu in the molten metal also reacts with Ti, generating new compounds, thereby forming a metallurgical bond between ceramics and Cu coatings.

6

3D Microstructure Reconstruction of Tetragonal Zirconia Polycrystalline

Grabowski Krzysztof

Journal of Casting & Materials Engineering

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2025

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Vol. 9, no. 1

1--7

EN

The microstructure of a material is fundamental to its properties and behavior under mechanical and thermal loads. Understanding the internal structure of a material and controlling the microstructure at the stage of ceramic materials synthesis are essential for designing materials with desired properties. This study focuses on the three-dimensional reconstruction of the microstructure of yttria-stabilized tetragonal zirconia polycrystalline (TZP). The goal was to create accurate digital models of the microstructure, which could be used for further material analysis. The study utilized images obtained through scanning electron microscopy (SEM), based on which the basic stereological parameters were determined. The microstructure reconstruction was performed using the Laguerre tessellation method, allowing for the generation of three-dimensional digital models of the microstructure that represent the material's internal structure. The results confirm that based on the basic stereological parameters obtained from two-dimensional cross-sections, three-dimensional reconstruction of the microstructure of polycrystalline zirconia is possible. This work, therefore, represents a step towards the effective design of ceramic materials with high performance parameters, through the control and optimization of their microstructure.

7

Enhancement of the Thermal Stability of Engine Block Alloy Al-10Si-1Cu-0.5Mg-0.5Ni-0.5Fe with Trace Additions of Ti and Zr

Kaiser Mohammad Salim

Engineering Transactions

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2025

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Vol. 73, iss. 1

3--28

EN

An investigation was carried out on the Al-10Si-1Cu-0.5Mg-0.5Ni-0.5Fe alloy engine block, emphasizing its physical and mechanical characteristics, as well as the presence of trace titanium (Ti) and zirconium (Zr). Three different alloys underwent processes such as homogenization, T6 solution treatment, quenching, and aging to observe both natural and artificial aging responses. The development of Al2Cu and Mg2Si phases within the aluminum matrix during the aging process led to the attainment of peak-aged strength. However, this strength diminished in the over-aged condition due to precipitation coarsening and recrystallization phenomena. The addition of Ti effectively refined the α-Al grain structure and led to the formation of thermally stable nano-sized Al3Ti dispersoids, which did not significantly enhance strength but prevented a drastic decline in the strength of the thermally damaged alloy. The simultaneous addition of Ti and Zr to the alloy further facilitated the precipitation of Al3(Ti, Zr) dispersoids, enhancing this capability. Trace addition reduced the alloys' toughness as well as thermal conductivity to a small extent due to grain refinement and precipitation formation, but these properties improved during aging due to recovery and recrystallization. Microstructural analysis of the alloys indicated that trace additions facilitated the formation of more finely distributed grains, contributing to grain refinement and preventing recrystallization in the over-aged state. The enhanced homogeneity of the grains due to trace additions was further supported by fractography studies.

8

Zirconium dioxide/tungsten carbide composite - influence of sintering technique on phase composition and microstructure

Pędzich Zbigniew, Wilmański Alan, Wojteczko Agnieszka, Komarek Sebastian, Kozień Dawid, Klimczyk Piotr

Composites Theory and Practice

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2025

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R. 25, nr 1

30--37

EN

The paper presents the results of a comparative experiment on sintering a particulate composite in the ZrO2/WC system containing significant amounts of carbide additive (20 or 50% by volume) utilizing spark plasma sintering (SPS) or high pressure high temperature (HPHT) techniques. The experiment was conducted using commercial zirconia and tungsten carbide powders. The main aim of the experiment was to verify if it was possible to use the HTHP technique to manufacture composite parts in order to increase the efficiency of the production process. The obtained results showed that the final microstructures of the composites produced by SPS and HPHT differ significantly in their phase composition and microstructure. The materials received by the HPHT process after consolidation contained a large volume of monoclinic zirconia phase, which was a serious disadvantage of the consolidated material due to strong susceptibility to cracking. Furthermore, the short time of sintering prevented the tungsten carbide grains from modifying their shape during the sintering process. The SPS process took more time, but in result the microstructure of the composites contained a non-transformed tetragonal zirconia phase and the carbide grains transformed their shape into convex and isometric ones.

9

Microstructure and selected mechanical properties of hot-rolled AA2024/SiC composite manufactured by powder metallurgy

Nikiel Piotr, Kutyła Patrycja

Composites Theory and Practice

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2025

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R. 25 nr 2

102-112

EN

This study investigates the microstructure and mechanical properties of an AA2024/SiC composite produced using powder metallurgy, followed by hot extrusion and multi-pass hot rolling. The composite, containing 5 wt% SiC, was fabricated by hot pressing at 450°C, then extruded and rolled with reductions of up to 66.2%. Microstructural analysis revealed uniform distribution of the SiC particles, grain refinement due to dynamic recrystallization (DRX), and enhanced particle dispersion with increasing rolling reduction. The hardness measurements showed significant improvement, with values increasing from 91 HV1 in the extruded state to 112 HV1 after the final rolling pass, and further grew to 151 HV1 after heat treatment. The tensile tests confirmed a strengthening effect, with the yield stress and ultimate tensile strength rising with rolling reduction from 205 MPa and 304 MPa (after initial rolling) to 236 MPa and 352 MPa (after the final rolling), respectively. Solution treatment and aging of the rolled composite resulted in a sharp increase in yield stress and ultimate tensile strength, reaching 293 MPa and 431 MPa after the first pass, increasing to 375 MPa and 484 MPa after the final pass. The study concludes that hot rolling significantly enhances the mechanical performance of AA2024/SiC composites, with grain refinement and particle fragmentation playing key roles in the strengthening mechanisms.

10

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.

11

Effect of major alloying elements Zn and Mg on microstructure and microhardness of AA7075 alloys and their composites

Mittal Prachi, Verma Ishu, Tomar Amit, Mahato Jayanta Kumar

Composites Theory and Practice

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2025

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R. 25 nr 2

90-101

EN

The present research work focuses on studying the effect of the major alloying elements on the microstructure and hardness of 7xxx series aluminium alloys and their composites. AA7075 aluminium alloy was used as the base material and different weight percentages of alloying elements zinc (Zn) and magnesium (Mg) were added at ratios 1:1, 2:1 and 3:1 to the base material. Afterwards, the modified aluminium alloys were used as matrix materials for the fabrication of aluminium alloy matrix composites (AAMCs) by adding different weight fractions of silicon carbide (SiC) as reinforcement material. Both the alloys and the AAMCs were fabricated by means of stir casting. XRD, SEM and EDX analysis of the modified aluminium alloys and their composites were carried out. Microstructures of the modified aluminium alloys and AAMCs were observed and the grain sizes were measured according to ASTM standards. Hardness tests of the fabricated specimens were carried out using Vickers microhardness testers and the hardness values were measured utilising the integrated software. It was observed that equiaxed grain structures were formed in both the modified Al alloys and their composites, indicating successful fabrication by means of the casting process; however, the average grain sizes of the fabricated specimens are dependent on the combination of wt% of reinforce ment and the composition of the Al alloys. Interestingly, a positive correlation with the weight percent ratio of Zn and Mg in the AA7075 was observed, indicating the potential for fine-tuning of the mechanical properties through proper selection of the alloying elements. It was also observed that the microhardness of the AAMCs fabricated with the mod ified Al alloys exhibits consistent improvement with an increasing weight fraction of SiC reinforcement, irrespective of the weight percentage ratio of the added Zn and Mg combination.

12

Application of AI and machine learning to the theory of composite materials

Mityushev V. V., Nurtazina K. B., Nauryzbayev N. Zh.

Composites Theory and Practice

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2025

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R. 25, nr 1

11--20

EN

The homogenization for classifying composites and determining their effective properties is an important optimal design problem of material sciences studied by mathematical modeling. The application of artificial intelligence (AI) and machine learning (ML) in the theory of composite materials is discussed. One of the main problems is the choice of characteristic ML features to describe multi-scale dispersed random composites and to predict their macroscopic properties. The complexity drastically increases when confronted with tasks such as estimating the effective properties of random composites, exploring optimal design scenarios with variable properties of components, or determining the optimal location and shape of inclusions since the myriad use of numerical computations proves challenging due to constraints in time and memory. In such instances, analytical, exact, or approximate formulas with the optimized parameters in symbolic form are preferred because powerful calculus methods can be applied to select the optimal parameters. The present paper is devoted to adequately choosing the parameters called structural sums, and corresponding analytical formulas. Such a formula is often asymptotic, and its correctly determined asymptotic precision shows its application area. We consider the question of the RVE size equivalent to the number of inclusions N per periodicity cell. It can be investigated numerically by solving a periodicity problem with N increasing up to stable effective constants not depending on N . Though one can find works in literature following these lines, they concern special distributions of inclusions with the numerical results performed for small N and for a small number of statistically investigated samples. A comprehensive study of 2D two-phase composites with equal circular inclusions is developed. It is demonstrated that using the concentration of inclusions and a contrast parameter is insufficient to properly study dispersed composites. The method of structural sums in combination with ML to improve model accuracy is applied. Based on the study, a new approach is suggested for selecting optimal parameters to analyze and classify two-dimensional dispersed composite structures. The included content fits 2020 Mathematics Subject Classification: 74Q15, 74-10.

13

Thermal Effects on the Structural and Mechanical Microstructure Parameters of Siliceous Sandstone from Kielce Upland

Pachnicz Michał

Civil and Environmental Engineering Reports

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2025

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Vol. 35, no. 1

250--271

EN

This study explores the thermal evolution of the microstructure and mechanical properties of Jurassic sandstone from the Kielce Upland, subjected to temperatures between 20°C and 1000°C. Combining microcomputed tomography (micro-CT) and nanoindentation techniques, it analyzes how geometric changes affect mechanical parameters. Key features like porosity, pore size distribution, and solid matrix thickness were assessed alongside indentation modulus (MIT) and hardness (HIT). The results reveal a strong correlation between microstructural changes and mechanical responses. At 200°C, microstructural compaction and thermal tightening lead to temporary strengthening. Above 600°C, increased porosity, microcrack formation, and rock matrix degradation cause significant reductions in mechanical properties. Reconstructed grayscale values are identified as reliable estimators for mechanical property changes, particularly for indentation modulus, when baseline parameters are available.

14

Sustainable use of leonardite biopolymers as a green alternative in soil improvement methods

Keskin Inan, Kahraman Selman, Vakili Amir Hossein, Kocaman Ayhan, Tatar Nurullah, Turan Metin

Archives of Mining Sciences

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2025

|

Vol. 70, no. 3

493--504

EN

Leonardite’s ability to stabilise marl, a challenging construction material, was confirmed through mechanical tests, including unconfined compressive strength, unconsolidated undrained triaxial tests, and chemical and microstructural analyses. Results confirmed that the strength improvement factor, cohesion improvement factor, and internal friction improvement factor significantly increased due to both the addition of Leonardite and the curing times. The addition of 15% Leonardite, along with curing periods of 7 to 14 days, resulted in considerable improvement factors ranging between 2 and 5, depending on the parameters investigated. Microstructural analysis confirmed that Leonardite could act as a filler, filling soil voids and reducing peaks associated with calcite content, which is responsible for the unfavorable behavior of marls. The formation of various functional groups and strong bands, such as carboxyl, hydroxyl, and carbonyl, as evidenced by FTIR analysis, was found to be responsible for improving the mechanical strength of samples containing Leonardite.

15

Mechanical and metallurgical properties of GTAW dissimilar welds between SUS304 and SA213T11 using ER308 filler metal, preliminary study

Hamdani Hamdani, Akhyar Akhyar, Rizwan Thaib, Sasmito Agus, Suhartono H Agus

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 8

77--89

EN

Dissimilar welding between austenitic stainless steel SUS304 and low alloy ferritic steel SA213T11 is widely used in the petrochemical and power generation industries because this combination is suitable for use in corrosive and high-temperature environments. This study presents a preliminary investigation of dissimilar metal welding between austenitic stainless steel SUS304 and low-alloy steel SA213T11 using Gas Tungsten Arc Welding (GTAW) with ER308 filler metal. The mechanical and metallurgical properties of the welded joints were evaluated through hardness testing, tensile testing, bend testing, and microstructural analysis. The results show that the welds produced are of acceptable quality, with sound bead appearance and no visible surface defects. Hardness values vary across different weld regions, with the weld zone exhibiting higher hardness due to the presence of δ-ferrite. Tensile tests indicate that the weld strength is comparable to or greater than the weaker base metal, and failure occurs outside the weld region. Microstructural observations reveal significant changes in the heat-affected zones and weld metal, influenced by the thermal cycle and filler composition. These findings provide insight into the performance of ER308 in joining dissimilar metals, which is relevant for applications in power and petrochemical industries.

16

Evaluating the stress intensity factor for R350HT rail steel in relation to microstructure parameters

Żak Sylwester, Junak Grzegorz, Woźniak Dariusz, Żak Artur, Chmiela Bartosz, Jabłońska Magdalena Barbara

Advances in Science and Technology. Research Journal

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2025

|

Vol. 19, no. 4

349–364

EN

The study highlights the advancement of rail transport, focusing on the distinct requirements of high-speed passenger transit and robust freight operations. Passenger rails emphasize geometric precision, such as straightness and minimal dimensional deviation, to reduce vibrations and improve safety and comfort. Freight rails, in contrast, require exceptional durability to withstand high axial loads, plastic deformation, and abrasive wear due to heavy tonnage. A key parameter for all rail types is the stress intensity factor (KIc), which ensures rail integrity by preventing crack propagation. The study confirmed that tested rail types (60E2, 54E4, and 49E1) meet the EN 13674-1 standard for mechanical properties, indicating effective heat treatment. Residual stress levels were found to be low, particularly in lighter rails, enhancing resistance to brittle fracture. All rails exhibited a fine, fully pearlitic microstructure with cementite lamellae spacing between 92 and 106 nm, contributing to mechanical strength and durability. The low residual stress and high KIc support extended rail life and safety, as larger critical crack sizes minimize fracture risk. These findings underline the reliability and safety of rail materials under operational conditions, with consistent pearlitic structures and optimized stress properties ensuring robust performance.

17

Effect of solution heat treatment on mechanical properties of Manaurite XM reformer tubes after long term service at elevated temperatures

Landowski Michał, Łabanowski Jerzy, Jurkowski Mateusz

Advances in Science and Technology. Research Journal

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2025

|

Vol. 19, no. 4

220--228

EN

The results of microstructure and mechanical properties changes of tubes made of Fe-Ni-Cr alloy G-X45NiCrNbTi35-25 after long term operation in methane reformer at elevated temperatures are presented. A method of tube regeneration by using solution heat treatment is proposed. Examinations included metallographic analysis with the use of light microscope (LM), scanning electron microscope (SEM), microanalysis of the chemical composition of precipitates (EDS) and static tensile tests. It was shown that solution heat treatment significantly affects the microstructure of the alloy, restoring the mechanical properties like tensile strength, yield strength and elongation of the tubes close to the values for the delivery condition, over 540 MPa, over 300 MPa and over 12%, respectively. The greatest improvement was observed in elongation, for samples after long-term operation at elevated temperature it was a minimum of 1.1% and after heat treatment 12.1% for the minimum requirement of 8% declared by producer (as cast).

18

Assessment of induced residual stresses and microstructure of Al/B4C/FA composite extruded by equal channel angular pressing

Irhayyim Tiba Qahtan, Gattmah Jabbar Qassim

Advances in Science and Technology. Research Journal

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2025

|

Vol. 19, no. 7

338--345

EN

This research evaluates the residual stresses and microstructure of rods fabricated from a hybrid aluminum matrix composite (Al1050/B4C/FA). The rod composite is subjected to various passes (cycles) using equal channel angular pressing (ECAP) at room temperature. Channel angles of 120° and 135° with pass numbers of 1P, 2P, 3P, 4P, 5P, and 6P are used to investigate the in-duced residual stresses (IRS) and examine the microstructure. The destructive cutting technique (CT) is employed to assess the state of IRS in the axial direction, and scanning electron micros-copy (SEM) is used to check the microstructure before and after severe plastic deformation (SPD). The results show that the values of residual stresses tend to increase due to the effects of SPD compared to the casting composite. As the ECAP cycles increase, the magnitudes of residu-al stresses start to change; the compressive state of residual stresses is near the rod surface, while the stresses are in tensile state near the center of the composite rod. The cycles of ECAP signifi-cantly impact the grain size reduction. The smallest grain size is observed at a die angle of 120° after 6 ECAP passes, measuring between 1 and 8 µm, while the grain size for the casted rods ranged from 4 to 15 µm.

19

Microstructure and mechanical properties of 15CDV6 steel in TIG-welded aircraft truss structures

Motyka Maciej, Rejman Edward, Bałon Paweł, Kiełbasa Bartłomiej

Advances in Mechanical and Materials Engineering

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2025

|

Vol. 42, nr 1

71-78

EN

Despite the undisputed dominance of composite materials in the construction of lightweight aircraft, steel structures still find use - especially for engine mounts. Weight reduction of the structure is achieved through the use of tubular trusses, usually made of structural steel for tempering. An increasing number of requirements for this type of construction and the development of steel metallurgy provide the basis for the introduction of new steel grades. This paper presents the testing results of a welded truss made of advanced 15CDV6 steel as a potential replacement for 30HGSA steel. The microstructure and hardness of characteristic zones of TIG-welded joints are discussed, as well as the results of static tensile testing of the parent material and welded joints.

PL

Pomimo niekwestionowanej dominacji materiałów kompozytowych w budowie lekkich pojazdów latających, konstrukcje stalowe nadal znajdują zastosowanie – szczególnie do mocowania silnika. Redukcję masy konstrukcji uzyskuje się poprzez zastosowanie kratownic rurowych, zwykle wykonanych ze stali konstrukcyjnej do ulepszania cieplnego. Zwiększone wymagania dla tego typu konstrukcji oraz rozwój metalurgii stali stanowią podstawę do wprowadzenia nowych gatunków stali. W artykule przedstawiono wyniki badań spawanej kratownicy wykonanej z zaawansowanej stali 15CDV6, jako potencjalnego zamiennika gatunku 30HGSA. Omówiono mikrostrukturę i twardość charakterystycznych stref złączy spawanych metodą TIG. a także wyniki statycznej próby rozciągania materiału rodzimego oraz połączeń spawanych.

20

Radiation shielding performance of high entropy alloys and derived nanomaterials towards nuclear irradiation/electromagnetic interference environments - fundamentals and technicalities

Kausar Ayesha

Advances in Materials Science

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2025

|

Vol. 25, nr 2(84)

73--103

EN

Recently, we note, high entropy alloys have attained incalculable research curiosity owing to remarkable elemental combinations, microstructural features, phase structure/stability, and superior physical characters mainly mechanical, thermal, and corrosion resistance under extreme working conditions. Interestingly, these materials have been found capable of sustaining the mechanical and anticorrosion properties at considerably high temperatures. In addition to the energy, engineering, and biomedical fields, high entropy alloys have been frequently explored for radiation protection applications. In nuclear sector, high entropy alloys and nanocomposite alloys exhibited worthy radiation defense towards wide ranging energetic particles including fast neutrons, gamma rays, electrons/ions, and other radionuclides. Consequently, plentiful high entropy alloys and related nanomaterial (nanocarbons, polymers, inorganic) designs have been found promising as functional bulk material/coatings for nuclear radiation as well as electromagnetic interference defiance. Accordingly, the appropriate experimental as well as theoretical approaches have been applied to study the structure, durability, and nuclear shielding effectiveness. In this context, various active mechanisms have been reported, including the micro-level changes, phase transformations, reduced thermal conductivity, and related radiation induced effects. Henceforth, this all-inclusive state-of-the-art overview, we believe, enlightens the significance of high performance high entropy alloys and nanomaterials for technical radiation defense applications against nuclear and electromagnetic interfering irradiations. In addition to radiation shielding parameters, the next generation high entropy alloy shields have been surveyed for synergistic mechanical, thermal, and anticorrosion features desirable against extreme nuclear/fission reactors environments.