Materials最新文献

{"title":"Utilizing Chicken Egg White and L-Cysteine for Green Synthesis of Carbon Dots: Rapid and Cost-Effective Detection of Cu²⁺ Ions.","authors":"Pablo Eduardo Cardoso-Ávila, Juan Luis Pichardo-Molina","doi":"10.3390/ma18030637","DOIUrl":"10.3390/ma18030637","url":null,"abstract":"<p><p>A novel green synthesis method was developed for sulfur-doped carbon dots (S-C-dots) using chicken egg white (CEW) and L-cysteine for the rapid and cost-effective detection of copper ions (Cu²⁺) in water. This one-pot, room-temperature, base-catalyzed approach eliminated the need for energy-intensive processes and purification steps, adhering to the principles of green chemistry. The synthesized S-C-dots were characterized using UV-Vis, FT-IR, fluorescence, EDS, XRD, and Z-potential analyses. Among the six samples tested, A060 demonstrated superior properties, achieving a detection limit of 3.3 ppb (52 nM) for Cu²⁺ in aqueous solutions. This study highlights the potential of S-C-dots as eco-friendly, accessible, and efficient tools for monitoring heavy metal contamination in drinking water, offering a promising solution to global water safety challenges.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11818816/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143409086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on Factors Affecting Asphalt Mixtures' Resistance to High-Frequency Freeze-Thaw in Plateau Areas.","authors":"Jinmei Wang, Jin Yang, Wenqi Wang, Bai Li, Chengjun He, Long He, Yalin Li","doi":"10.3390/ma18030640","DOIUrl":"10.3390/ma18030640","url":null,"abstract":"<p><p>Aiming at the problem that asphalt pavement materials in plateau areas are vulnerable to freeze-thaw damage, research was carried out on asphalt pavements of representative road sections, and the temperature within the pavement structure was monitored using buried sensors. Based on this, an indoor test method for high-frequency freeze-thaw was established, and UV, thermo-oxygen-aging and high-frequency freeze-thaw tests were combined. The effects of aging and maximum aggregate particle size on the resistance of asphalt mixtures to high-frequency freeze-thaw were investigated using the splitting strength ratio, mass-loss rate and void-ratio changes by employing the newly made RS-type modified asphalt in the laboratory. At the same time, the high-frequency freeze-thaw resistance of the asphalt mixture was compared with that of the SS/SMA-13 asphalt mixture on the top layer of a representative road section. The results show that UV aging at 180 h followed by thermal-oxygen aging at 120 h has the greatest impact on the asphalt mixture; in this condition, the high-frequency freeze-thaw-cycle asphalt mixture with freeze-thaw damage is affected by the rule of change of the third-degree polynomial. In the plateau environment conditions, compared with the original pavement material (SS-type modified asphalt), the RS-type modified asphalt has better anti-aging properties, adhesion properties and elasticity performance.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11818809/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143409006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced Performance of Austenitic Oxide Dispersion-Strengthened 316L Steel: A Study on Y₂O₃ Reinforcement and Corrosion Behaviour.","authors":"Jan Pokorný, Jiří Kubásek, Črtomir Donik, David Nečas, Vojtěch Hybášek, Jaroslav Fojt, Anna Dobkowska, Irena Paulin, Jaroslav Čapek, Matjaž Godec","doi":"10.3390/ma18030641","DOIUrl":"10.3390/ma18030641","url":null,"abstract":"<p><p>This study explores the mechanical and corrosion properties of yttria-reinforced 316L stainless steel. Powder precursor materials were prepared using mechanical alloying. Varying yttria (Y₂O₃) contents (1, 3, and 5 wt%) were used to assess its impact on the steel's properties. X-ray diffraction and scanning electron microscopy confirmed the successful dispersion of Y₂O₃ within the matrix, with the formation of chromium carbides during spark plasma sintering (SPS). The mechanical properties, including hardness and compressive yield strength, improved with increasing Y₂O₃ contents, with the highest strength observed in the 316L-5Y₂O₃ sample. However, corrosion resistance decreased with higher yttria concentrations. The 3 wt% Y₂O₃ sample exhibited the highest corrosion rate due to localized corrosion in areas enriched with oxide particles and chromium carbides. Electrochemical testing revealed that carbide formation and Cr-depleted regions from SPS processing contributed to the corrosion behaviour. These findings suggest that while yttria reinforcement enhances mechanical strength, optimizing the Y₂O₃ content and processing methods is crucial to balance both mechanical and corrosion performance in ODS 316L stainless steel.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11818875/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143408892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-H Curve Estimation and Air Gap Optimization for High-Performance Split Core.","authors":"Minjoong Kim, Myungseo Lee, Sijeong Lee, Jaeyun Lee, Jihwan Song","doi":"10.3390/ma18030644","DOIUrl":"10.3390/ma18030644","url":null,"abstract":"<p><p>The current transformer (CT)-based energy harvesting method has gained considerable attention for low-power devices. Accurate estimation of the B-H curve is essential to develop a high-performance CT, as it closely relates to the electromagnetic behavior of CT material. However, the existing estimation methods for the B-H curve face several drawbacks, which include process complexity and a high cost. This study presented an intuitive method to estimate the B-H curve based on the experimentally obtained resistance-voltage data. The performance of the CT core is obtained based on the estimated B-H curve, which exhibited an error of only 2.6% when compared to the experimental results for the most accurate case. Additionally, we analyzed split-core performance deterioration caused by the presence of an air gap. The air gap formation of the split core was closely related to the surface roughness, which significantly influenced core performance. The air gap range that minimizes the reduction in performance is predicted and validated through simulations and experiments. This research highlights a straightforward approach to obtaining the B-H curve of magnetic CT core material. We believe that this study provides the design guidelines needed to develop a high-performance CT core, including considerations for core geometry and the recommended air gap range.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11820830/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143408740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure and Selected Properties of Coatings Deposited by Arc Spraying Under in Inert Atmosphere Containing In Situ Fabricated Fe-Al Intermetallic Phases.","authors":"Paweł Kołodziejczak, Mariusz Bober, Tomasz M Chmielewski, Michał Baranowski","doi":"10.3390/ma18030646","DOIUrl":"10.3390/ma18030646","url":null,"abstract":"<p><p>Intermetallic compounds from the Fe-Al system are attracting increasing attention due to their outstanding properties, including excellent mechanical performance, low density, corrosion, and oxidation resistance, as well as resistance to sulfidation, carburization, and wear at elevated temperatures. These unique characteristics make Fe-Al intermetallics promising candidates for high-temperature and harsh environmental applications. However, challenges such as brittleness and low plasticity have hindered their broader use. By exploring the impact of spray conditions on coating properties, this study contributes to enhancing the performance and functionality of Fe-Al coatings in industrial applications, where durability and resistance to extreme conditions are essential. This article presents the results of research on the production of composite coatings from the Fe-Al system with in situ fabricated intermetallic phases. For this purpose, arc spraying in an inert gas was used. The coating manufacturing process was carried out by simultaneously melting two different electrode filler wires, aluminum and steel, in a stream of argon. The obtained coatings were subjected to tests of roughness, adhesion to the substrate, and microstructure. It was shown that both the roughness and adhesion to the substrate of coatings sprayed in air are higher than those sprayed in argon. The increase in roughness results from the greater oxidation of coatings sprayed in air, while better adhesion is the result of the formation of coatings at a higher temperature. Metallographic studies have shown that during the spraying process, the in situ synthesis of intermetallic phases occurred. The results showed the local occurrence of intermetallic phases from the Fe-Al system. Among the two dominant phases, i.e., Al and the Fe alloy, there are also the following phases: FeAl₃, FeAl₂, and Fe₂Al₅. Furthermore, in layers sprayed in an inert atmosphere, the share of oxides is small.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11820642/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143409049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Comparative Study in Microstructure and Mechanical Properties of Symmetric and Asymmetric Double-Sided FSW Joints of AA7A65.","authors":"Chen Chen, Yichao Zhu, Zhiping He, Hongjian Lu, Weifeng Xu, Tengfei Cui, Wenjing Liu, Chenyang Qiu, Zhanping Gao","doi":"10.3390/ma18030645","DOIUrl":"10.3390/ma18030645","url":null,"abstract":"<p><p>Double-sided friction stir welding (DS-FSW) demands a low requirement of the welding tool and equipment and can lower the heat input, showing advantages in joining thick-plate joints. However, the intrinsic twice thermal cycle inevitably leads to the twice grain growth and softening, troubling the performance of the joints. To alleviate this phenomenon, this work proposed an asymmetric DS-FSW (Asy-DS-FSW) in which the first weld and second weld are obtained via a large tool and a small tool, respectively. The results suggest that the Asy-DS-FSW effectively refines the grains and inhibits twice-grain growth in the 27 mm thick AA7A65 joints. The hardness of Asy-DS-FSW is higher and more homogeneously distributed than the conventional symmetric DS-FSW (Sym-DS-FSW). The ultimate tensile strength of the slices is enhanced by 0.5-11%, and the eased strain localization can be achieved by the Asy-DS-FSW, compared with the Sym-DS-FSW. This work offers valuable references to the high-quality joining of thick-plate aluminum alloys in aerospace.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11818705/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143408898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Large-Scale Metasurface Simulation Using Local-Segmented Approach.","authors":"Shiyao Wang, Site Zhang, Naitao Song, Donglin Xue","doi":"10.3390/ma18030649","DOIUrl":"10.3390/ma18030649","url":null,"abstract":"<p><p>The complicated electromagnetic couplings between nanostructures present substantial challenges in the design and simulation of metasurfaces, especially large-scale elements. The couplings are typically neglected in a conventional simulation. We introduce a computational framework that includes the electromagnetic coupling effects between meta-atoms. Decomposing the incident field and segmenting the computing range for individual local simulations allows for an effective and accurate simulation of the entire metasurface. Numerical examples of a 2 mm diameter cylindrical metalens with a numerical aperture of 0.9 and a 1 mm aperiodic beam splitter show the deviation from the conventional method is reduced by 97% compared to the rigorous method, while the computation times are 10 times and 4 times faster than the rigorous methods, respectively.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11819928/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143408914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of Low-Temperature (Al)GaN on N-Polar GaN Films Grown by MOCVD on Vicinal SiC Substrates.","authors":"Yong Yang, Xianfeng Ni, Qian Fan, Xing Gu","doi":"10.3390/ma18030638","DOIUrl":"10.3390/ma18030638","url":null,"abstract":"<p><p>N-polar GaN HEMTs feature a natural back-barrier and enable the formation of low-resistance Ohmic contacts, with the potential to suppress short-channel effects and current collapse effects at sub-100 nm gate lengths, rendering them particularly promising for high-frequency communication applications. In this study, N-polar GaN films were grown on C-face SiC substrates with a 4° misorientation angle via MOCVD. By employing a two-step growth process involving LT-GaN or LT-AlGaN, the surface roughness of N-polar GaN films was reduced to varying degrees, accompanied by an improvement in crystalline quality. The growth processes, including surface morphology at each growth stage, such as the AlN nucleation layer, LT-GaN, LT-AlGaN, and the initial 90 nm HT-GaN, were investigated. The results revealed that a high V/III ratio and low-temperature growth conditions for the low-temperature layers, along with the introduction of a minor amount of Al, influenced adatom migration behavior and facilitated the suppression of step bunching. Suppressing step bunching during the initial growth stages was demonstrated to be critical for improving the surface quality and crystalline quality of N-polar GaN films. An N-polar GaN HEMT epitaxial structure was successfully achieved using the optimized surface morphology with a dedicated Fe-doped buffer process.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11818682/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143408172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Durability of Cutting Tools Obtained by U-FAST Technology in Particleboard Machining.","authors":"Joanna Wachowicz, Jacek Wilkowski, Tomasz Dembiczak, Robert Kruzel","doi":"10.3390/ma18030636","DOIUrl":"10.3390/ma18030636","url":null,"abstract":"<p><p>The basic material used for tools for machining wood and wood-based materials is WC-Co (Tungsten Carbide with Cobalt)-cemented carbide. The advantages of WC-Co carbides are significant resistance to high temperatures, high hardness, and wear resistance. Wood-based materials, such as particleboard, are particularly difficult to machine due to their considerable inhomogeneity and the presence of various types of hard particle inclusions, such as sand. In addition, unlike metals, wood has a low thermal conductivity, which means that most of the heat generated during milling is transferred to the tool. The consequence of this phenomenon is an increased tool temperature. In addition, the use of a coolant is not possible when machining wood-based materials. The durability of carbide blades is mainly influenced by grain size and cobalt content. When analysing WC-Co as a tool material, it is necessary to consider how it is obtained, as this can also significantly affect its properties. This paper presents the results of a durability study of cutting blades produced by the innovative Upgraded Field-Assisted Sintering Technology (U-FAST) sintering method during particleboard milling. The wear of the blades was measured until the wear value, i.e., the maximum loss at the contact surface VB_max, was 0.2 mm. Three groups of WC-Co carbides with different WC grain sizes were tested: 0.1, 0.4, and 0.8 µm. Three rotational speeds were used: 12,000, 15,000, and 18,000 rpm. In the machinability tests, blades with a WC grain size of 0.8 µm showed a twofold increase in tool life compared to commercial blades with a similar grain size gradation.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11818859/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143408373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Trace Sc Addition on Microstructure and Mechanical Properties of Al-Zn-Mg-Cu-Zr Alloy.","authors":"Yuchen Huang, Linfei Xia, Huabing Yang, Chengguo Wang, Yuying Wu, Xiangfa Liu","doi":"10.3390/ma18030648","DOIUrl":"10.3390/ma18030648","url":null,"abstract":"<p><p>Transition element microalloying is important for improving the properties of Al-Zn-Mg-Cu alloys. Nevertheless, along with its high costs, increasing Sc content generates a harmful phase, limiting the strength of the alloy. In this experiment, we reduced the amount of Sc added to a Zr-containing Al-Zn-Mg-Cu alloy by one order of magnitude. The microstructure and mechanical properties of the alloys were studied by means of tensile tests, field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The findings indicate that the alloys' mechanical properties were progressively enhanced with the increase in Sc content from 0 to 0.04%. After adding 0.04% Sc, the tensile strength and yield strength of the Al-Zn-Mg-Cu-Zr-Sc alloy increased by 20.9% and 24.3%, reaching 716 MPa and 640 MPa, respectively, and the elongation decreased, but still reached 12.93%. The strengthening mechanisms of the trace addition of Sc are fine grain strengthening and precipitate and disperse strengthening, and Al₃(Sc, Zr) particles hinder the dislocation and grain boundary movement. Drawing on insights from other studies on Sc microalloying in Al-Zn-Mg-Cu alloys, this experiment successfully reduced the amount of Sc added by an order of magnitude, the alloys properties were improved, and the effect of strengthening remained good.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 3","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11820551/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143408837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}