rss_2.0Materials Science-Poland FeedSciendo RSS Feed for Materials Science-Polandhttps://sciendo.com/journal/MSPhttps://www.sciendo.comMaterials Science-Poland Feedhttps://sciendo-parsed.s3.eu-central-1.amazonaws.com/663bab89dd1c3d1f87119679/cover-image.jpghttps://sciendo.com/journal/MSP140216Evaluation of cracking risk of 80MnSi8-6 nanobainitic steel during hot forging in the range of lower temperature limitshttps://sciendo.com/article/10.2478/msp-2024-0011<abstract> <title style='display:none'>Abstract</title> <p>Nanobainitic steels exhibit an exceptional combination of high strength, good plasticity, impact toughness, and wear resistance. They are suitable for the production of large mass components through the open-die forging process. Subsequently, the forgings are air-cooled. An obstacle of this method is the extended time required for the large forgings to undergo a bainitic transformation, making the industrial implementation of this process economically unjustifiable. Nevertheless, nanobainitic steels also allow for the open-die forging of small batches of structural elements with high property requirements. A technological limitation lies in the necessity of performing a series of operations, leading to a prolonged processing time dependent on the shape of the product and the degree of deformation. Therefore, inter-operational reheating is often necessary, incurring costs and time consumption. This is particularly relevant to forgings with a mass ranging from a few to several dozen kilograms, which, due to their low thermal capacity, rapidly dissipate heat to the surroundings and tools. Designing an economical process with a limited number of reheating cycles requires advanced knowledge of material behavior under thermo-mechanical deformation parameters, including boundary conditions where a significant decrease in plasticity occurs and the risk of crack initiation. To obtain this information, a comprehensive analysis of the influence of thermo-mechanical parameters applied during the deformation of nanobainitic steel at relatively low temperatures on the flow characteristics and crack formation was conducted. To achieve this goal, the Digital Image Correlation method, the finite element method modeling considering damage criteria, and the macrostructural evaluation of deformed specimens were employed.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00112024-05-29T00:00:00.000+00:00Mechanical properties and quantum mechanical simulations of natural rubber composites with cerium complexes under aging conditionshttps://sciendo.com/article/10.2478/msp-2024-0013<abstract> <title style='display:none'>Abstract</title> <p>Enhancing the service life of natural rubber (NR) products, including antioxidants, is crucial to prevent rubber degradation and enhance its oxidation resistance. Phenolic antioxidant 2246 and cerium complex of p-amino salicylic acid (PAS-Ce) are utilized as NR antioxidants. Numerous studies have qualitatively analyzed the antioxidant mechanisms of these compounds. Building upon this perspective, this study quantitatively assessed the protective mechanisms of these antioxidants by combining experimental data with molecular simulations. Additionally, it compared their impacts on the thermal oxidative aging performance of NR. The findings revealed that the PAS-Ce/NR system exhibited the highest mechanical performance retention following multiple days of thermal-oxidative aging. Analyzing the PAS-Ce/NR system through ATR-FTIR and DTA techniques demonstrated that it had the lowest C=O content after thermal-oxidative aging. Furthermore, calculating the activation energy required for thermal-oxidative aging decomposition using the Kissinger and FWO methods indicated that PAS-Ce/NR had the highest activation energy, suggesting superior inhibitory effects against thermal-oxidative aging. Quantum mechanical simulations also illustrated that the dissociation energy of the O-H bond in antioxidants 2246 and PAS-Ce was lower than that of the C-H bond in NR. However, PAS-Ce exhibited a quicker capture of radical species, effectively delaying the oxidation reaction rate of NR molecular chains and thus more efficiently inhibiting the aging process. These insights contribute significantly to comprehending the antioxidative mechanisms in NR aging.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00132024-05-27T00:00:00.000+00:00Shear strengthening of deficient RC deep beams using NSM FRP system: Experimental and numerical investigationhttps://sciendo.com/article/10.2478/msp-2024-0012<abstract> <title style='display:none'>Abstract</title> <p>It is essential to retrofit deep beams with shear inadequacies because these beams, although they have the same shear and flexural reinforcements as ordinary beams, are more susceptible to shear failure. Hence, it is of great significance to overcome the shear weaknesses in deep beams. This research paper aims to experimentally examine the effectiveness of near-surface mounted (NSM) carbon fiber reinforced polymer (CFRP) for retrofitting reinforced concrete (RC) deep beams subjected to shear forces. The study involved three different types of specimens. The first specimen was constructed with concrete throughout its span and included shear stirrups. The second specimen was divided into two halves, with one half lacking shear reinforcements and the other half having them. The third specimen had steel web reinforcement in one half of the span, while the other half was strengthened using NSM CFRP U-wrap strips and externally bonded horizontal CFRP strips. The proposed strengthening method significantly increased the shear strength of the deep beams, surpassing that provided by steel web reinforcement alone. Furthermore, the NSM CFRP strengthened specimen exhibited a change in failure mode from shear to flexural failure. In comparison to the control beam without stirrups, the beams strengthened with NSM CFRP U-wrap strips demonstrated an impressive 82% improvement in shear strength, while the beam with shear reinforcement showed a 23 % enhancement in load capacity. The proposed strengthened scheme is capable of enhancing the structural performance and load-carrying capacity effectively. A finite element model was generated utilizing ABAQUS software to simulate the behavior of the tested deep beams and verified against the experimental outcomes. The numerical models successfully predicted the behavior of the RC deep beams strengthened with NSM CFRP when compared to the experimental data.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00122024-05-27T00:00:00.000+00:00Analysis of the influence of dies geometry on the process extrusion force and properties of the extrudate obtained in the process of cold extrusion of 7075 aluminum alloy by the KOBO methodhttps://sciendo.com/article/10.2478/msp-2024-0008<abstract> <title style='display:none'>Abstract</title> <p>The KOBO extrusion process is an unconventional method of extrusion based on the phenomenon of superplasticity as an effect of a special state caused by the oscillatory motion of the die at a certain angle a certain frequency. It significantly lowers the extrusion force and makes it possible to extrude lightweight metals and alloys (e.g. aluminum and magnesium alloys) in cold extrusion with high extrusion ratios compared to conventional hot extrusion.</p> <p>This work studies the influence of the tool (die) geometry on process realization parameters and the properties of the extrudate. Experimental studies of cold KOBO extrusion were performed using dies with different face portion geometry. The obtained extrudate obtained from EN-AW 7075 aluminum billets was examined for mechanical properties and macro/microstructure, showing that, with adequate modifications to the tool face part geometry, it is possible to lower the extrusion force and obtain extrudate with desired properties.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00082024-05-22T00:00:00.000+00:00The influence of nano-SiO emulsion on sulfate resistance of cement-based groutshttps://sciendo.com/article/10.2478/msp-2024-0010<abstract> <title style='display:none'>Abstract</title> <p>Sulfate attack is one of the most significant durability issues for cement-based grouts, which are widely used to repair concrete structures in sulfate-rich environments. The purpose of this study was to investigate the impact of nano-SiO<sub>2</sub> emulsion on the sulfate resistance of cement-based grouts. The durability of the mixes was evaluated on the basis of weight loss and compressive strength. X-ray diffraction (XRD) and scanning electron microscopy (SEM) of hardened grout matrix were used to analyze the hydration products and microstructure of the hardened grout matrix. The results indicate that the hydration degree of nano-SiO<sub>2</sub>-modified samples is higher than that of the control sample. The compressive strength from highest to lowest was 16 NSE, 10 NSE, NSP, and the control sample. The XRD and SEM results suggest that the deterioration of properties may be attributed to the formation and growth of ettringite (AFt) crystals, which may result in crack generation and extension and in the corrosion of gypsum, leading to exfoliation. The addition of nano-SiO<sub>2</sub> to cement-based grouts through a preprepared emulsion, which facilitates dispersion within the cement matrix, has the potential to reduce AFt and gypsum contents, enhance microstructure density, decrease the migration channels of <inline-formula><alternatives><inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/j_msp-2024-0010_ieq_001.png"/><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msubsup><mml:mrow><mml:mtext>SO</mml:mtext></mml:mrow><mml:mn>4</mml:mn><mml:mrow><mml:mn>2</mml:mn><mml:mo>−</mml:mo></mml:mrow></mml:msubsup></mml:mrow></mml:math><tex-math>\[\text{SO}_{4}^{2-}\]</tex-math></alternatives></inline-formula>, and ultimately improve the resistance to sulfate attack. This work will provide a novel route to enhance the sulfate resistance of cement-based grouts, which may be serviced in a sulfate-rich environment.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00102024-05-22T00:00:00.000+00:00Technological challenges in manufacturing of vacuum gauge thermionic cathode using thick-film technologyhttps://sciendo.com/article/10.2478/msp-2024-0007<abstract> <title style='display:none'>Abstract</title> <p>This paper focuses on the development of a technological challenges of manufacturing the planar ceramic vacuum sensor based on the principles of hot-cathode ionization in the Bayard-Alpert configuration. The goal is to simplify the technological process by utilizing planar platinum structures with gold electrical paths instead of 3-dimensional structures. Various methods were tested, including the use of carbon-based SVM (Sacrifice Volume Materials) materials, but without success. Wet-etching using potassium hydroxide on Al<sub>2</sub>O<sub>3</sub> substrates showed promise results. The findings highlight the challenges and progress made in developing the thermo-emittercomponent of the vacuum sensor.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00072024-05-22T00:00:00.000+00:00Advances in the application of biosynthesized carbon dots as fluorescent probes for bioimaginghttps://sciendo.com/article/10.2478/msp-2024-0009<abstract> <title style='display:none'>Abstract</title> <p>Carbon dots (CDs) are emerging as versatile fluorescent nanoprobes for bioimaging applications due to advantages like tunable emissions, excellent biocompatibility, facile surface functionalization, and ease of synthesis. This review summarizes recent advances in applying biosynthesized CDs for sensitive bioimaging. CDs derived from sustainable biomass sources through green techniques like hydrothermal and microwave synthesis demonstrate bright, excitation-tunable photoluminescence spanning visible to near-infrared spectra. Careful control of synthesis parameters and surface passivation strategies enhance quantum yields above 50% comparable to toxic semiconductor dots. Conjugation with polymers, peptides, and recognition elements like antibodies impart solubility and selectivity towards cancer cells and biomarkers. <italic>In vitro</italic> validation in standard lines shows targeted organelle imaging abilities. <italic>In vivo</italic> administration reveals renal clearance pharmacokinetics with preferential tumor accumulation via enhanced permeability effects. Average tumor growth inhibition around 50-80% was achieved in mouse xenografts using CDs-drug formulations through combined therapeutic effects of chemotherapy and photothermal ablation under imaging guidance. However, concerns regarding toxicity from chronic exposures, large-scale reproducible manufacturing, and multimodal imaging capabilities need redressal prior to further clinical translation.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00092024-05-22T00:00:00.000+00:00Comparative analysis of microstructure and selected properties of WC-Co-Cr coatings sprayed by high-velocity oxy fuel on S235 and AZ31 substrateshttps://sciendo.com/article/10.2478/msp-2024-0002<abstract> <title style='display:none'>Abstract</title> <p>The purpose of this work was to carry out comparative studies of WC-Co-Cr coatings deposited using the high velocity oxy fuel (HVOF) method onto two types of substrate material: structural steel S235 and magnesium alloy AZ31. The influence of the substrate material type on the microstructure, phase composition, crystallite size, porosity, Vickers microhardness, instrumental hardness (H<sub>IT</sub>), Young’s modulus (E<sub>IT</sub>), and fracture toughness was investigated. For both substrates, the deposited coatings deposited were characterized with fine-grained and compact microstructure. The X-ray diffraction (XRD) revealed presence of following phases: WC, W<sub>2</sub>C, Co<sub>0.9</sub>W<sub>0.1</sub>, and Co<sub>3</sub>W<sub>9</sub>C<sub>4</sub>. The WC phase was the most desirable and stable one with crystallites were below 100 nm. On the other hand, the size of the W<sub>2</sub>C crystallites was below 30 nm. The coatings obtained showed porosity values equal to 2.3 ± 0.4 vol% and 2.8 ± 0.7 vol% for AZ31 and S235, respectively. The average Vickers microhardness for both types of sample was appproximately 1200 HV0.3. The average H<sub>IT</sub> values for carbide particles and metallic matrix were around 29 GPa and 6.5 GPa, respectively. In the case of E<sub>IT</sub>, it was around 620 GPa and 190 GPa for WC and Co-Cr, respectively. The differences between coatings were negligible. The E<sub>IT</sub> value for both coatings was equal to 344 ± 11 GPa. The fracture toughness was around 4.5 MPa · m<sup>1/2</sup> in both cases. The investigations revealed that it is possible to replace steel substrate material with a much lighter equivalent, in this case AZ31 alloy, without deterioration of the coating properties.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00022024-05-08T00:00:00.000+00:00Experimental investigation of stereolithography and digital light processing additive manufactured palletshttps://sciendo.com/article/10.2478/msp-2024-0001<abstract> <title style='display:none'>Abstract</title> <p>Pallets are a tertiary form of packaging used for stacking, storing, protecting, or transporting goods in supply chains. They are utilized as a base for the unitization of goods for logistics and warehousing. Moreover, pallets can be manufactured using wood, plastic, metal, and corrugated paper, which can be used as material-handling equipment. With several products being transported worldwide and with year-on-year growth, it would be beneficial to make lightweight pallets. Such pallets are recyclable, easy to clean, cheap, and durable to maintain and store. Though most of the pallets are widely available for basic purposes, applications involving high-end bio-packings and transportation of special chemicals require specialized pallets to be manufactured like polymers to ensure a negligible chemical reaction, light in weight, and attenuation in freight capacity, thereby widespread reduction in wastage. With advancements, job to job and immediate requirements, additive manufacturing has the potential to close the gap for jobs with short lead times. If the design process of new pallets has limits the creation of specific codes, the transitions will be smoother in rapid prototyping. This work describes the development of polymer pallets by taking advantage of stereolithography (SLA) and digital light processing (DLP) technology for 3D printing pallets in correlation to injection moulding. After the pallets are designed and manufactured, AM technologies can be applied to specified standards, and the pallets then undergo tensile strength, elongation, and hardness tests. The analysis was carried out for configurable geometries adapting to fork lifting, conveyor, racking, and stacking conditions. Analytical and numerical solutions were carried out to understand the stress and deflections for each geometry and its wide range of applications for pallets.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00012024-05-08T00:00:00.000+00:00Effects of infill density on mechanical properties of additively manufactured chopped carbon fiber reinforced PLA compositeshttps://sciendo.com/article/10.2478/msp-2024-0003<abstract> <title style='display:none'>Abstract</title> <p>In this present study, the fused deposition modeling (FDM) method was used to fabricate the composites. Before three-dimensional (3D) printing, samples were designed according to the ASTM D256, D790 and D3039 standards for impact, flexural and tensile tests, respectively, using Onshape software before conversion to an STL file format. Afterward, the digital file was sliced with infill densities of 60%, 80%, and 100%. The composite samples contained chopped carbon fiber (cCF) and poly lactic acid (PLA), as reinforcement and matrix, respectively. The cCF/PLA (simply called cCFP) filaments were printed into various cCFP composite (cCFPC) samples, using a Viper Share bot 3D machine with different infill densities before the aforementioned mechanical testing. The tensile strength of cCFP were obtained as 25.9MPa, 26.9MPa and 34.75MPa for 60%, 80% and 100% infill density cCFP samples, respectively. Similarly, the flexural strength of cCFP were obtained as 11.8MPa, 12.55MPa and 18.4MPa and impact strength was 47.48kJ/m<sup>2</sup>, 48.45kJ/m<sup>2</sup> and 48.96kJ/m<sup>2</sup> for 60%, 80% and 100% infill density cCFP samples, respectively. The fractured/tested samples were examined and analyzed under a scanning electron microscope (SEM) to investigate the presence of fiber and void in the tensile sample. Based on the experimental results, it was evident that a high infill density of 100% with the highest reinforcement exhibited maximum impact strength, tensile and flexural strengths and moduli when compared with other lower carbon content of cCFPC samples. Therefore, the optimal 3D-printed cCFPC sample could be used for engineering application to benefit from properties of the polymer matrix composite materials and possibilities through additive manufacturing (AM).</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00032024-05-08T00:00:00.000+00:00Enhanced catalytic activity of zeolitic imidazolate frameworks (ZIF-8) polyelectrolyte complex composites membranes by laser etchinghttps://sciendo.com/article/10.2478/msp-2024-0004<abstract> <title style='display:none'>Abstract</title> <p>The effect of laser etching on the surface properties of composite polyelectrolyte complex (PEC) based membranes as mixed matrix membranes was studied. The PECs were prepared by the stoichiometric mixing of cationic PDDA (poly(diallyl dimethyl ammonium chloride)) and anionic PSS (poly(sodium 4-styrene sulfonate)) as polyelectrolytes with various contents of ZIF-8 as filler. Composite membranes usually display improved bulk properties depending on the nature of the filler, but the surface properties are often dictated by the matrix covering the surface. The PEC composite membranes were then subjected to laser etching, resulting in the enhanced exposure of embedded ZIF-8 particles within the PEC structure in an attempt to improve the surface properties of the composite membrane. The crystal structure, morphology, and distribution of zinc at the PECs surface, before and after laser etching, were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDS), respectively. In order to evaluate the improvement of the surface properties of the laser-etched membranes, a model experiment involving a catalytic reaction was chosen. The pristine and laser treated surfaces were tested for their catalytic activity for the transesterification of triglycerides present in soybean oil with methanol at a temperature of 150°C. Interestingly, the laser-etched PECs displayed substantially enhanced activity compared to the original composite PEC membranes as a result of surface erosion. These results could be interesting for the future development of composite membranes with improved surface properties where the filler needs to expose the surface of the membranes.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2024-00042024-05-08T00:00:00.000+00:00Water absorption and mechanical behaviour of green fibres and particles acting as reinforced hybrid composite materialshttps://sciendo.com/article/10.2478/msp-2023-0051<abstract> <title style='display:none'>Abstract</title> <p>This paper highlights the results of an experimental study on the preparation and characterization of <italic>Luffa cylindrica</italic> fiber (LCF) and groundnut shell particle (GSP) reinforced phenol-formaldehyde (PF) hybrid composites. The amount of LCFs was fixed at 25 wt%, while the amount of groundnut shell particles ranged from 0 to 25 wt%. Observations were made regarding the water absorption and thickness swelling behaviour of prepared hybrid composites. In addition, the mechanical behaviours of hybrid composites have been studied under both dry and wet conditions. In comparison to dry conditions, the mechanical properties of the hybrid composites were lower when they were wet. Hybrid composites comprising 25% <italic>Luffa cylindica</italic> fibre and 15% groundnut shell particle (25LCF/15GSP) exhibit the highest level of mechanical properties under both conditions. The percentages of water absorption and thickness swelling increase as groundnut shell particles increase. The composite 25LCF/25GSP exhibited the highest percentage of water absorption and thickness swelling. Compared to date palm leaf (DPL)-reinforced composites, 25LCF/15GSP showed more significant mechanical and physical properties. We concluded that the inclusion of groundnut shell particles in LCF/PF composites substantially improved the mechanical properties of the hybrid composite. The range of increment, however, was narrower under moist conditions compared to dry conditions.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2023-00512024-04-03T00:00:00.000+00:00Investigation of silver nanoparticles embedded in extracted gelatins from camel, bovine, and fish bones for possible use in radiation dosimetryhttps://sciendo.com/article/10.2478/msp-2023-0043<abstract> <title style='display:none'>Abstract</title> <p>Gelatins from camel, bovine, and fish bones were successfully extracted by using chemical pretreatment and heating methods. The bones were demineralized for 3 days at ambient temperature using hydrochloric acid solutions (0.5–1 M), and the collagen was partially hydrolyzed by preheating in distilled water at 75–80°C for 3 h, followed by extraction temperature at 90°C for 1 h. Free-standing films of gelatin entrained with silver nanoparticles (Gel/AgNPs) at low concentrations (1.25, 2.5, and 5 mM) were synthesized as radiation dosimeters. A high-energy ultrasonic homogenizer was used to dissolve the gelatin in distilled water and to disperse the AgNPs in the gelatin. The nanocomposites’ morphology and crystallinity were investigated using scanning electron microscopy (SEM), optical absorption, and Fourier transform infrared (FTIR) spectroscopies. Dose enhancement was assessed using X-ray irradiations with beam energies below and above silver K-edge. The beam was configured by setting the X-ray generator at 15, 25.5, and 35 kV potential and a beam current of 1 mA. An X-ray detector is used to detect the number of electrons after passing through Gel/AgNPs samples. The use of AgNPs embedded in gelatin caused the enhancement of X-ray radiation absorption, and the highest percentage of linearity for the dosimeter was found to be 90% in the optical range of 395 nm to 425 nm. The preliminary results demonstrated that Gel/AgNPs material may be used in radiation dosimetry for low-energy radiotherapy sources.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2023-00432024-04-02T00:00:00.000+00:00Performance of green high-strength concrete incorporating palm oil fuel ash in harsh environmentshttps://sciendo.com/article/10.2478/msp-2023-0042<abstract> <title style='display:none'>Abstract</title> <p>The corrosion of steel reinforcement by chloride is commonly recognized as a key factor that contributes to the degradation of durability in reinforced concreae structures. Using supplementary cementitious materials, such as industrial and agricultural waste materials, usually enhances the impermeability of the concrete and its corrosion resistance, acid resistance, and sulfate resistance. This study’s primary purpose is to examine the effects of replacing ordinary Portland cement (OPC) with ultrafine palm oil fuel ash (U-POFA) on the corrosion resistant performance of high-strength green concrete (HSGC). There were four HSGC mixes tested; the first mix contained 100% OPC, while the other mixes replaced OPC mass with 20%, 40%, and 60% of U-POFA. The performance of all HSGC mixes containing U-POFA on workability, compressive strength, porosity, water absorption, impressed voltage test, and mass loss was investigated at 7, 28, 60, and 90 days. Adding U-POFA to mixes enhances their workability, compressive strength (CS), water absorption, and porosity in comparison with mixes that contain 100% OPC. The findings clearly portrayed that the utilization of U-POFA as a partial alternative for OPC significantly enhances the corrosion-resistant performance of the HSGC. In general, it is strongly advised that a high proportion of U-POFA be incorporated, totaling 60% of the OPC content. This recommendation is the result of its significance as an environmentally friendly and cost-effective green pozzolanic material. Hence, it could contribute to the superior durability performance of concrete structures, particularly in aggressive environmental exposures.</p> <sec> <title style='display:none'>Highlights</title> <p><list list-type="bullet"> <list-item><p>The corrosion resistance performance of high-strength green concrete was investigated.</p></list-item> <list-item><p>Ultrafine palm oil fuel ash as a partial alternative of cement mass with 20%, 40%, and 60% was used.</p></list-item> <list-item><p>HSGC performance was evaluated in terms of workability, compressive strength, water absorption, porosity, impact stress testing, and mass loss.</p></list-item> </list></p> </sec> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2023-00422024-04-02T00:00:00.000+00:00Effects of B content on wear and corrosion resistance of laser-cladded Co-based alloy coatingshttps://sciendo.com/article/10.2478/msp-2023-0040<abstract> <title style='display:none'>Abstract</title> <p>To improve the surface properties of Ti alloy, (Co<sub>34</sub>Fe<sub>8</sub>Cr<sub>29</sub>Ni<sub>8</sub>Si<sub>7</sub>)<sub>100–<italic>x</italic></sub> B<sub><italic>x</italic></sub> alloy, coatings were prepared by laser cladding. The coatings—mainly composed of TiCr, Fe<sub>0.1</sub>Ti<sub>0.18</sub>V<sub>0.72</sub>, CoTi, Ti<sub>2</sub>Ni, and TiB—and amorphous phases were investigated in terms of microstructure, wear resistance, and corrosion resistance. The results showed that the microhardness of the Co-based coatings first increased and then decreased with the increase of B content. When the B content was 6%, the microhardness of the coating increased up to 1210 HV<sub>0.2</sub> which was 3.4 times that of TC4 alloy substrate. The coatings exhibited diverse wear mechanisms that gradually transitioned from severe fatigue spalling and oxidative wear to slightly abrasive wear. The corrosion current density of Co-based coatings in 3.5 wt% NaCl solution first increased and then decreased as B contents increased. Coatings with 4% B content, however, exhibited the best corrosion resistance, which was most suitable for improving the corrosion resistance of Ti alloy.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2023-00402024-04-02T00:00:00.000+00:00Residual fly ash from pyrometallurgical processes as a partial replacement for Portland cement in mortars: a study of structural evolution and determination of compressive strengthhttps://sciendo.com/article/10.2478/msp-2023-0050<abstract> <title style='display:none'>Abstract</title> <p>Mortar mixtures were prepared by partial replacement of Portland cement with 0%, 10%, and 15% of residual fly ash to determine the structural evolution and compressive strength at 3, 7, 14, and 28 days. Portlandite, calcite, ettringite, iron oxide, silicon oxide, and sillimanite were identified in the standard mortar, and, additionally, magnetite was identified in the mortar with 10% and 15% fly ash. X-ray diffraction peaks corresponding to portlandite and ettringite increased in intensity with increasing curing time as a result of the consolidation of mineral species. The SEM analysis revealed that the standard mortar contained mainly portlandite and ettringite at 28 days, while the samples with 10% and 15% fly ash contained particles of fly ash coated with portlandite and ettringite, particles with a smooth surface, and particles of fly ash with signs of attack on their surfaces. The sc increased when the age of the mortar and the substitution of Portland cement by fly ash was increased from 3 to 28 days and from 0 to 15%, respectively.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2023-00502024-04-02T00:00:00.000+00:00Synergistic emulsification of polyetheramine/nanofluid system as a novel viscosity reducer of acidic crude oilhttps://sciendo.com/article/10.2478/msp-2023-0049<abstract> <title style='display:none'>Abstract</title> <p>Oil is a critical raw material for energy and industry, the depletion of conventional oil reserves necessitates efficient extraction and production of unconventional resources like acidic crude oil. However, its high viscosity poses significant challenges for transportation and processing. To address these challenges, this study developed a novel emulsion viscosity reducer. We designed a nanofluid based on a synergistic polyetheramine/nanofluid system consisting of alkyl ethoxy polyglycosides (AEG) as a green surfactant, SiO<sub>2</sub> nanoparticles, and an organic alkali polyetheramine. The mixture was evaluated for its viscosity reduction and emulsification performance with acidic crude oi obtained from Qinghe oil production plant in Shengli Oilfield. The results showed that the optimized viscosity reducer achieved a remarkable reduction rate of 98.1% at 50◦C in crude oil viscosity from 6862 mPa·s to 129 mPa·s. This demonstrated the reducer effectively transformed acidic crude oil into a low viscosity oil-in-water (O/W) emulsion with high stability. Furthermore, the core imbibition simulation tests demonstrated that the viscosity reducer could improve the recovery of acidic crude oil from 29.6% to 49.4%, indicating the potential application of the optimized viscosity reducer in the exploitation of acidic crude oil. In conclusion, this study developed a novel emulsion viscosity reducer, which can reduce the viscosity and improve recovery of acidic crude oil by emulsifying into O/W emulsion. The optimized formula has potential for practical application in the exploitation of acidic crude oil.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2023-00492024-03-27T00:00:00.000+00:00Mechanical and corrosion properties of highly porous Ta-Nb-Sn alloy for intervertebral disc in spinal applicationshttps://sciendo.com/article/10.2478/msp-2023-0048<abstract> <title style='display:none'>Abstract</title> <p>In this study, low Young’s modulus, highly porous Ta-Nb-Sn alloy foam was manufactured by using the space holder method. The aim of this study is development of an alloy with high wear resistance, with Young’s modulus, with good imaging (MRI, CT) properties, and with high bioactivity. Ta alloy foam can be used in spinal applications (intervertebral disc) or dental applications. The space holder method enables the manufacturing of open-cell foam with a low elastic modulus. Powder mixtures were prepared through mechanical alloying. Carbamide was used to form pores. Ta has suitable strength, ductility, corrosion resistance, and biocompatibility. Ta has high price, however, and a high melting temperature, high activity, and high density. Nb addition lowered the melting temperature, elastic modulus, and cost of using Ta. The sinterability of Ta was enhanced by Sn addition. The corrosion behaviour of Ta alloy was examined. Young’s modulus was determined by compression and ultrasonic tests. Tomography and radiography tests were also used.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2023-00482024-03-21T00:00:00.000+00:00In vitro evaluation of stainless steel orthodontic wires coated with TiO and TiO:Ag for their anti-adhesive and antibacterial efficacy against in a sucrose-enriched environmenthttps://sciendo.com/article/10.2478/msp-2023-0047ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2023-00472024-03-21T00:00:00.000+00:00Investigating the steel–cement interface in high-temperature, high-pressure carbon dioxide environmentshttps://sciendo.com/article/10.2478/msp-2023-0045<abstract> <title style='display:none'>Abstract</title> <p>This study investigates the impact of high-temperature, high-pressure carbon dioxide on the steel-cement interface, crucial in engineering structures and carbon capture storage systems. Experiments conducted on N80 steel and ordinary portland cement in synthetic aquifer brine revealed that CO<sub>2</sub> exposure significantly exacerbates steel corrosion and cement degradation. The corrosion current density of steel increased to 1.2 <italic>μ</italic>A/cm<sup>2</sup> after six months in CO<sub>2</sub>, compared to 0.3 <italic>μ</italic>A/cm<sup>2</sup> in unexposed samples. Cement samples showed a marked decline in mechanical properties, with hardness reducing from 1.25 GPa (giga-Pascal) in control samples to 0.65 GPa after six months. The steel—cement interface integrity also diminished, as evidenced by a decrease in acoustic impedance from 45.0 M-Rayl to 34.0 M-Rayl over six months. These results emphasize the need for advanced materials and strategies to enhance the durability and safety of structures in CO<sub>2</sub>-rich environments.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/msp-2023-00452024-03-21T00:00:00.000+00:00en-us-1