Materials最新文献

{"title":"Enhanced Wear Resistance and Thermal Dissipation of Copper-Graphene Composite Coatings via Pulsed Electrodeposition for Circuit Breaker Applications.","authors":"Daniele Almonti, Daniel Salvi, Nadia Ucciardello, Silvia Vesco","doi":"10.3390/ma17236017","DOIUrl":"https://doi.org/10.3390/ma17236017","url":null,"abstract":"<p><p>Copper, though highly conductive, requires improved wear resistance and thermal dissipation in applications that involve continuous movement and current-induced vibrations, such as power breakers. Conventional solutions, such as copper-tungsten alloys or lubricant use, face limitations in durability, friction, or environmental impact. This study explores the development of copper-graphene (Cu-GNPs) composite coatings using pulsed electrodeposition to enhance the tribological, thermal, and mechanical properties of circuit breaker components by adopting an industrially scalable technique. The influence of deposition bath temperature, duty cycle, and frequency on coating morphology, hardness, wear resistance, and heat dissipation was systematically evaluated using a 2³ full factorial design and an Analysis of Variance (ANOVA). The results revealed that optimized pulsed electrodeposition significantly improved coating performance: hardness increased by 76%, wear volume decreased by more than 99%, and friction coefficient stabilized at 0.2, reflecting effective graphene integration. The addition of graphene further improved thermal diffusivity by 19.5%, supporting superior heat dissipation. These findings suggest that pulsed copper-graphene composite coatings offer a promising alternative to traditional copper alloys, enhancing the lifespan and reliability of electronic components through improved wear resistance, lower friction, and superior heat transfer.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Evaluation of Concrete Blended with Eco-Friendly Bio-Sulfur as a Cement Replacement Material.","authors":"Wonchang Kim, Taehyung Kim, Taegyu Lee","doi":"10.3390/ma17236016","DOIUrl":"https://doi.org/10.3390/ma17236016","url":null,"abstract":"<p><p>Bio-sulfur (BS), extracted from landfill bio-gas via microbial methods, was examined herein as a potential cement replacement material. The study developed five modified BS variants through limestone incorporation processes (sulfur-to-limestone ratios of 1:0.5, 1:1, 1:1.5, 1:3, and 1:5). The study revealed that modified BS with higher limestone ratios demonstrates significant workability and strength reductions of over 50% with increased content, leading to the adoption of a sulfur-to-limestone ratio of 1:1. The concrete specimens exhibited compressive strength improvements of up to 12% with increased BS content, while the UPV showed proportional increases with increased BS content that remained independent of the water/binder (W/B) ratio. Statistical analysis confirmed significance with <i>p</i>-values below 0.05. XRD analysis identified initial cement hydrate peaks at 3 d that evolved into distinct Mg-S hydrate and Ca-Al-S hydrate formations in the BS-containing specimens by 28 d.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modification of Uniaxial Stress-Strain Model of Concrete Confined by Pitting Corroded Stirrups.","authors":"Zhiwei Miao, Yifan Liu, Kangnuo Chen, Xinping Niu","doi":"10.3390/ma17236014","DOIUrl":"https://doi.org/10.3390/ma17236014","url":null,"abstract":"<p><p>To investigate the impact of stirrup pitting corrosion on the stress-strain model of core concrete under compression, this study, based on existing corroded steel specimens, establishes a probabilistic model of the residual cross-sectional area distribution of steel bars to reasonably evaluate the effect of pitting on the mechanical performance of stirrups. Considering the tension stiffening effect in reinforced concrete, a time-dependent damage model of corroded steel bars in concrete was determined, and the existing stress-strain model of concrete confined by stirrups was ultimately modified, establishing a time-dependent constitutive model that incorporates the effects of stirrup pitting corrosion. A comparison with previous experimental results indicates that the revised model presented in this paper can appropriately reflect the changes in the mechanical performance of concrete confined by corroded stirrups. The results of this study can provide theoretical support for the refined numerical analysis of reinforced concrete structures under the erosion of chloride ions.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perovskite in Triboelectric Nanogenerator and the Hybrid Energy Collection System.","authors":"Tong Wu, Zequan Zhao, Yin Lu, Hanzhang Yang, Xiaoning Liu, Xia Cao, Ning Wang","doi":"10.3390/ma17236019","DOIUrl":"https://doi.org/10.3390/ma17236019","url":null,"abstract":"<p><p>In the context of escalating energy demands and environmental sustainability, the paradigm of global energy systems is undergoing a transformative shift to innovative and reliable energy-harvesting techniques ranging from solar cells to triboelectric nanogenerators (TENGs) to hybrid energy systems, where a fever in the study of perovskite materials has been set off due to the excellent optoelectronic properties and defect tolerance features. This review begins with the basic properties of perovskite materials and the fundamentals of TENGs, including their working principles and general developing strategy, then delves into the key role of perovskite materials in promoting TENG-based hybrid technologies in terms of energy conversion. While spotlighting the coupling of triboelectric-optoelectronic effects in harnessing energy from a variety of sources, thereby transcending the limitations inherent to single-source energy systems, this review pays special attention to the strategic incorporation of perovskite materials into TENGs and TENG-based energy converting systems, which heralds a new frontier in enhancing efficiency, stability, and adaptability. At the end, this review highlights the remaining challenges such as stability, efficiency, and functionality for applications in TENG-based energy-harvesting systems, aiming to provide a comprehensive overview of the current landscape and the prospective trajectory of the role of perovskite materials in TENG-based energy-harvesting technologies within the renewable energy sector.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of Strength Parameters of Composite Reinforcement Consisting of Steel Member, Adhesive, and Carbon Fiber Textile.","authors":"Maciej Adam Dybizbański, Katarzyna Rzeszut, Saydiolimkhon Abdusattarkhuja, Zheng Li","doi":"10.3390/ma17236022","DOIUrl":"https://doi.org/10.3390/ma17236022","url":null,"abstract":"<p><p>The main aim of the study was the determination of the strength parameters of composite bonded joints consisting of galvanised steel elements, an adhesive layer, and Carbon-Fiber-Reinforced Plastic (CFRP) fabric. For this purpose, shear laboratory tests were carried out on 60 lapped specimens composed of 2 mm thick hot-dip galvanised steel plates of S350 GD. The specimens were overlapped on one side with SikaWrap 230 C carbon fibre textile (CFT) using SikaDur 330 adhesive. The tests were carried out in three series that differed in overlap length (15 mm, 25 mm, and 35 mm). A discussion on the failure mechanism in the context of the bonding capacity of the composite joint was carried out. We observed three forms of joint damage, namely, at the steel-adhesive interface, fibre rupture, and mixed damage behaviour. Moreover, an advanced numerical model using the commercial finite element (FE) program ABAQUS/Standard and the coupled cohesive zone model was developed. The material behaviour of the textile was defined as elastic-lamina and the mixed-mode Hashin damage model was implemented with bi-linear behaviour. Special attention was focused on the formulation of reliable methodologies to determine the load-bearing capacity, failure mechanisms, stress distribution, and the strength characteristics of a composite adhesive joint. In order to develop a reliable model, validation and verification were carried out and self-correlation parameters, which brought the model closer to the laboratory test, were proposed by the authors. Based on the conducted analysis, the strength characteristics including the load-bearing capacity, failure mechanisms, and stress distribution were established. The three forms of joint damage were observed as steel-adhesive interface failure, fibre rupture, and mixed-damage behaviour. Complex interactions between the materials were observed. The most dangerous adhesive failure was detected at the steel and adhesive interface. It was also found that an increase in adhesive thickness caused a decrease in joint strength. In the numerical analysis, two mechanical models were employed, namely, a sophisticated model of adhesive and fabric components. It was found that the fabric model was very sensitive to the density of the finite element mesh. It was also noticed that the numerical model referring to the adhesive layer was nonsensitive to the mesh size; thus, it was regarded as appropriate. Nevertheless, in order to increase the reliability of the numerical model, the authors proposed their own correlation coefficients α and β, which allowed for the correct mapping of adhesive damage.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Vanadium Addition on the Wear Resistance of Al_0.7CoCrFeNi High-Entropy Alloy.","authors":"Marzena Tokarewicz, Malgorzata Gradzka-Dahlke, Wojciech J Nowak, Andrzej Gradzik, Miroslaw Szala, Mariusz Walczak","doi":"10.3390/ma17236021","DOIUrl":"https://doi.org/10.3390/ma17236021","url":null,"abstract":"<p><p>High-entropy alloys are of interest to many researchers due to the possibility of shaping their functional properties by, among other things, the use of alloying additives. One approach to improving the wear resistance of the AlCoCrFeNi alloy is modification through the addition of titanium. However, in this study, an alternative solution was explored by adding vanadium, which has a completely different effect on the material's structure compared to titanium. The effect of vanadium additives on changes in the microstructure, hardness, and wear resistance of the Al_0.7CoCrFeNi alloy. The base alloys Al_0.7CoCrFeNi and Al_0.7CoCrFeNiV_0.5 were obtained by induction melting. The results showed that the presence of vanadium changes the microstructure of the material. In the case of the base alloy, the structure is biphasic with a visible segregation of alloying elements between phases. In contrast, the Al_0.7CoCrFeNiV_0.5 alloy has a homogeneous solid solution bcc structure. The presence of vanadium increased hardness by 33%, while it significantly reduced friction wear by 73%. Microscopic observations of friction marks indicate differences in the wear mechanisms of the two materials.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the Macro-/Micrometric Characteristics and Mechanical Properties of Clayey Sandy Dredged Fill in the Guangdong Area.","authors":"Qiunan Chen, Xiaodi Xu, Ao Zeng, Yunyang Yan, Yan Feng, Kun Long, Chenna Qi","doi":"10.3390/ma17236018","DOIUrl":"https://doi.org/10.3390/ma17236018","url":null,"abstract":"<p><p>The study of dredged fill in Guangdong (GD), China, is of great significance for reclamation projects. Currently, there are relatively few studies on dredged fill in Guangdong, and there are many differences in the engineering characteristics of dredged fill foundations formed through land reclamation and natural foundations. In order to have a more comprehensive understanding of the physico-mechanical properties of blowing fill in the coastal area of GD and to understand the effect of its long-term creep row on the long-term settlement and deformation of buildings, the material properties, microstructure, elemental composition, triaxial shear properties, and triaxial creep properties of dredged fill in Guangdong were studied and analyzed through indoor geotechnical tests, scanning electron microscopy (SEM), X-ray diffraction (XRD), and conventional triaxial shear tests and triaxial creep tests. The test results showed that the Guangdong dredged fill is characterized by a high water content, high pore ratio, and high-liquid-limit clayey sand, and the mineral composition is dominated by quartz and whitmoreite. The scanning electron microscopy results showed that the particles of the dredged fill showed an agglomerated morphology, and the surface of the test soil samples had scaly fine flakes and a fragmented structure. In the triaxial shear test, the GD dredged fill showed strain hardening characteristics, and the effective stress path showed continuous loading characteristics; the consolidated undrained shear test showed that the GD dredged fill had shear expansion characteristics under low-perimeter-pressure conditions. It was found that, with an increase in bias stress, the axial strain in the consolidated undrained triaxial creep test under the same perimeter pressure conditions gradually exceeded the axial strain in the consolidated drained triaxial creep test. The results of this study are of theoretical and practical significance for further understanding the mechanical properties of silty soils in the region and for the rational selection of soil strength parameters in practical engineering design.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the Preparation and Test Method of Transformer Oil Used in Laboratory.","authors":"Zeming Sun, Minxia Shi","doi":"10.3390/ma17236010","DOIUrl":"https://doi.org/10.3390/ma17236010","url":null,"abstract":"<p><p>The power transformer is one of the most important parts of a power system. The transformer oil in a transformer not only increases its insulation strength, but also helps its cooling. Cellulose particles are one of the main factors affecting the breakdown characteristics of transformer oil, and the withstand voltage test can effectively detect the quality of transformer oil. Therefore, the withstand voltage test on transformer oil with different cellulose particle content levels in the laboratory can determine the breakdown characteristics of transformer oil and the method of improving the insulation strength of power transformers. However, there is lack of a set of effective preparation and test methods of transformer oil for laboratory use in the industry. Based on national standards and engineering practice, this paper puts forward a method of preparing transformer oil with different cellulose particle content levels in the laboratory and a method of the withstand voltage test on transformer oil in the laboratory, which can improve the efficiency and the scientificity of such experiments.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved Method for the Calculation of the Air Film Thickness of an Air Cushion Belt Conveyor.","authors":"Bo Song, Hongliang Chen, Long Sun, Kunpeng Xu, Xiaoyong Ren","doi":"10.3390/ma17236020","DOIUrl":"https://doi.org/10.3390/ma17236020","url":null,"abstract":"<p><p>The air film thickness is an important parameter of an air cushion belt conveyor, which directly affects the compressed air supply power and operating resistance of the system. Therefore, it is important to calculate the bottom thickness of the gas film accurately in the design stage. A calculation method for the thickness of a conveyor air cushion was derived based on the mathematical model of the air cushion flow field for a multi row uniformly distributed air cushion structure. Meanwhile, the algorithm was validated based on a Fluent 3D flow field numerical simulation and experiments. Through verification, it was found that due to the algorithm's assumption that the increase in the gas flow rate only existed at the axis of the gas hole, there was a sudden change in the calculation results of the gas flow rate at the axis of the gas hole. The sudden change in the gas flow rate had caused the calculation results of the air cushion thickness to experience abrupt and discontinuous changes. Furthermore, the calculation method for air cushion thickness was revised based on the verification results. Compared with the experimental test results, the average error of the calculation results of the algorithm proposed in this paper was 14.27%.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance and Emission Characteristics of a Small Gas Turbine Engine Using Hexanol as a Biomass-Derived Fuel.","authors":"Tomasz Suchocki","doi":"10.3390/ma17236011","DOIUrl":"https://doi.org/10.3390/ma17236011","url":null,"abstract":"<p><p>The global transition to renewable energy has amplified the need for sustainable aviation fuels. This study investigates hexanol, a biomass-derived alcohol, as an alternative fuel for small-scale gas turbines. Experimental trials were conducted on a JETPOL GTM-160 turbine, assessing blends of 25% (He25) and 50% (He50) hexanol with kerosene (JET A) under rotational velocities ranging from 40,000 to 110,000 RPM. The parameters measured included thrust-specific fuel consumption (TSFC), turbine inlet and outlet velocities, and the emission indices of NO_x and CO. The results demonstrated that the He25 and He50 blends achieved comparable thermal efficiency to pure JET A at high rotational velocities, despite requiring higher fuel flows due to hexanol's lower heating value. CO emissions decreased significantly at higher velocities, reflecting improved combustion efficiency with hexanol blends, while NO_x emissions exhibited a slight increase, attributed to the oxygen content of the fuel. This study contributes a novel analysis of hexanol-kerosene blends in gas turbines, offering insights into their operational and emission characteristics. These findings underscore hexanol's potential as an environmentally friendly alternative fuel, aligning with global efforts to reduce fossil fuel dependency and carbon emissions.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}