Materials最新文献

{"title":"Deposition Contribution Rates and Simulation Model Refinement for Polysilicon Films Deposited by Large-Sized Tubular Low-Pressure Chemical Vapor Deposition Reactors.","authors":"Jicheng Zhou, Jianyong Zhan, Bowen Lv, Yan Guo, Bingchun Jiang","doi":"10.3390/ma17235952","DOIUrl":"10.3390/ma17235952","url":null,"abstract":"<p><p>Tunnel oxide passivating contact cells have become the mainstream form of high-performance photovoltaic cells; however, the key factor restricting the further improvement of tunnel oxide passivating contact cell performance lies in the deposition process technology of high-quality polysilicon films. The experimental optimization cost for the deposition of large-sized polysilicon films in low-pressure chemical vapor deposition reactors is enormous when conducted in the temperature range of 800-950 K; hence, the necessity to develop effective computer simulation models becomes urgent. In recent years, our research group has conducted two-dimensional simulation research on large-sized, low-pressure chemical vapor deposition. This article focuses on analyzing the influence of gas-phase chemical reactions on the contribution rate of polysilicon film deposition under a mixed atmosphere of H₂ and SiH₄. The findings indicate that when using SiH₄ as the precursor reactants with a gas pressure not exceeding 100 Pa, SiH₄ contributes more than 99.6% to the deposition of polysilicon films, while the contribution rate of intermediates from chemical reactions to film deposition is less than 0.5% with 860-900 K. The influence of temperature on the contribution rate of gas-phase intermediates is negligible. It is found that simulating complex multi-step chemical reactions is highly resource-intensive, making it difficult to achieve the three-dimensional simulations of large-sized tubular LPCVD reactors. Based on the in-depth analysis of the mechanism and simulation results, a simplified model neglecting the complex multi-step chemical reaction process has been proposed. Through employing this refined and simplified model, the two-dimensional simulation of the polysilicon thin films deposition process in the large-sized tubular low pressure chemical vapor deposition reactor will become more effective and resource efficient.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643910/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837367","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":"Meta-Analysis of Materials and Treatments Used in Ophthalmic Lenses: Implications for Lens Characteristics.","authors":"Clara Martinez-Perez, Ana Paula Oliveira","doi":"10.3390/ma17235949","DOIUrl":"10.3390/ma17235949","url":null,"abstract":"<p><strong>Purpose: </strong>This meta-analysis evaluates the evolution, applications, and recent advancements in the materials and treatments used in ophthalmic lenses, focusing on their effectiveness, comfort, and safety, while also considering sustainability as a key factor.</p><p><strong>Methods: </strong>The study was registered with PROSPERO and conducted following the PRISMA and AMSTAR-2 guidelines. A systematic review was performed across databases such as PubMed, Web of Science, and Scopus, without time or language restrictions. Observational studies analyzing optical materials and ophthalmic lens treatments were included, and a random-effects model was applied due to the high heterogeneity observed among the studies.</p><p><strong>Results: </strong>Nine studies were included that evaluated different materials, such as CR-39^®, PMMA with nanoparticles, and high-refractive-index polymers, with variability in refractive index (1.49 to 1.90) and light transmission (84.15% to 99%). Treatments like anti-reflective and abrasion-resistant coatings improved optical quality and durability. However, significant heterogeneity and publication bias were identified, limiting the generalizability of the results.</p><p><strong>Conclusions: </strong>The materials and treatments evaluated play a crucial role in the optical quality, durability, and comfort of lenses. Although advancements in sustainable materials show promise for reducing environmental impact, challenges remain in terms of cost and production. It is recommended to establish more stringent standards and promote research to improve the consistency and performance of ophthalmic lenses while ensuring sustainability.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643459/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837020","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":"Investigation on a Novel Reinforcement Method of Grouting Sleeve Connection Considering the Absence of Reserved Reinforcing Bars in the Transition Layer.","authors":"Sheng Gu, Jun Yang, Saifeng Shen, Xing Li","doi":"10.3390/ma17235961","DOIUrl":"10.3390/ma17235961","url":null,"abstract":"<p><p>In practical engineering, due to quality inspections of connections between prefabricated components and construction errors, reserved reinforcing bars in the transition layer may be partially insufficient or even completely absent. This defect significantly impacts the structural performance of sleeve connections, particularly under tensile or shear forces. This paper proposes a novel reinforcement method to address the connection issues caused by the absence of reserved reinforcing bars in the transition layer and verifies its feasibility through systematic experiments. To this end, this paper proposed a novel reinforcement method of grouting sleeve connection considering the absence of reserved bars in the transition layer, and 45 specimens with different reinforcement parameters were fabricated and tested under tension. Before verifying the reliability of the novel reinforcement method, nine specimens were fabricated and tested to verify the weldability of grouting sleeves and reinforcing bars. According to the test results, the fully grouted sleeves, including Grade 45 steel and Q345, showed good weldability with the HRB400 steel bars, while the ductile iron grouted sleeve showed poor weldability. When the single-sided welding length was greater than or equal to six times the diameter of the post-retrofitted connecting steel bar (<i>D</i>₂), the primary failure mode observed in specimens utilizing the novel reinforcement method was the fracture of the prefabricated steel bar. The novel reinforcement method could be used to repair the defect of the grouting sleeve connection considering the absence of reserved reinforcing bars in the transition layer. When the single-sided welding length was 4<i>D</i>₂, with a relative protective layer thickness of 2<i>D</i>₂, and using C60 grade reinforcement material, this combination of conditions represented the critical condition to avoid weld failure between the grouting sleeve and the post-retrofitted connecting steel bars. In practical reinforcement projects, it is suggested that the single-sided welding length should be 5<i>D</i>₂, the relative protective layer thickness should be 3<i>D</i>₂, and the reinforcement material strength should be C60.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643728/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837550","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 Numerical Study of Topography and Roughness of Sloped Surfaces Using Process Simulation Data for Laser Powder Bed Fusion.","authors":"Beytullah Aydogan, Kevin Chou","doi":"10.3390/ma17235955","DOIUrl":"10.3390/ma17235955","url":null,"abstract":"<p><p>The simulation of additive manufacturing has become a prominent research area in the past decade. Process physics simulations are employed to replicate laser powder bed fusion (L-PBF) manufacturing processes, aiming to predict potential issues through simulated data. This study focuses on calculating surface roughness by utilizing 3D surface topology extracted from simulated data, as surface roughness significantly influences part quality. Accurately predicting surface roughness using a simulation remains a persistent challenge. To address this challenge, the L-PBF technique with two different cases (pre- and post-contouring) was simulated using two-step process physics simulations. The discrete element method was utilized to simulate powder spreading, followed by the Flow-3D melting simulation. Ten layers were simulated at three different linear energy density (LED) combinations for both cases, with samples positioned at a 30-degree angle to accommodate upskin and downskin effects. Furthermore, a three-dimensional representation of the melted region for each layer was generated using the thermal gradient output from the simulated data. All generated 3D layers were stacked and merged to consolidate a 3D representation of the overall sample. The surfaces (upskin, downskin, and side skins) were extracted from this merged sample. Subsequently, these surfaces were analyzed, and surface roughness (Sa values) was calculated using MATLAB. The obtained values were then compared with experimental results. The downskin surface roughness results from the simulation were found to be within the range of the experimental results. This alignment is attributed to the fact that the physics simulation primarily focuses on melt pool depth and width. These promising findings indicate the potential for accurately predicting surface roughness through simulation.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643527/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837350","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":"Improved Surface Quality and Microstructure Regulation in High Power Fiber Laser Cutting of Stainless Steel Grid Plates.","authors":"Linjiang Xu, Chunming Wang, Fei Yan, Zhuangxi Hu, Wei Zhang","doi":"10.3390/ma17235959","DOIUrl":"10.3390/ma17235959","url":null,"abstract":"<p><p>In order to disintegrate nuclear fuel rods in the grid connection structure, a 10 kW fiber laser was used to cut a stainless steel simulation component with four layers of 3 mm thick plates and 12 mm gaps. The slit width is regarded as an important indicator to evaluate the cutting quality of the four-layer stainless steel plate. The results showed that good laser cutting quality can be successfully achieved under the proper process parameters. The widths of the cut seams of the four layers of grating after cutting were 1.25, 1.65, 1.80, and 1.92 mm. As the auxiliary gas pressure decreased layer by layer, the metal melting pool for the first two plates was mainly destroyed by the auxiliary gas. The cutting quality was good, and the slit area was mainly austenite with the presence of some ferrite. The third- and fourth-layer plates almost had no gas flow to assist blowing off, so the cut surface was an uneven melting pit, the cutting quality was poor, and the cut seam area ferrite content was higher than the upper plate cut seam area. At the same time, due to the lack of airflow cooling of the bottom plate, high laser energy, and long heating time, grain coarsening occurred, while grain deformation and a large number of dislocations existed. It can provide process support and technical guidance for the disintegration of nuclear fuel rods.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643447/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837428","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":"Hybrid Microwave/Solar Energy Harvesting System Using 3D-Printed Metasurfaces.","authors":"Argyri Drymiskianaki, Zacharias Viskadourakis, George Kenanakis","doi":"10.3390/ma17235969","DOIUrl":"10.3390/ma17235969","url":null,"abstract":"<p><p>In this study, a hybrid energy harvesting system based on a conventional solar cell combined with 3D-printed metasurface units is studied. Millimeter-scale metasurface units were fabricated via the stereolithography technique, and then they were covered with conductive silver paint, in order to achieve high electric conductivity. The performance of single, as well as two-unit metasurface harvesters, was thoroughly investigated. It was found that both of them produced voltage, which peaks at their resonance frequency, demonstrating efficient energy harvesting behavior in the microwave regime. Then, the metasurface units were connected with a commercially available photovoltaic panel and the performance of the hybrid system was examined under different environmental conditions, modifying the light intensity (i.e., light, dark and shadow). It was shown that the proposed hybrid harvesting system produces a sizable voltage output, which persists, even in the case when one of the components does not contribute. Furthermore, the performance of the hybrid harvester is found to be adequate enough, although optimization of the harvesting circuit is required in order to achieve high efficiency levels. All in all, the presented experimental evidence clearly indicates the realization of a rather promising hybrid energy harvesting system, exploiting two distinct ambient energy sources, namely light and microwaves.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643723/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142836872","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":"Reinforcing Bus Living Space with Recycled Carbon Fibers from Expired Prepreg in the Aircraft Industry.","authors":"Miguel Angel Martínez, Daniel Lavayen-Farfán, Juana Abenojar, María Jesús López-Boada, Daniel García-Pozuelo","doi":"10.3390/ma17235958","DOIUrl":"10.3390/ma17235958","url":null,"abstract":"<p><p>Due to increasing mobility and energy conservation needs, improving bus and coach safety without adding weight is essential. Many crashes with fatal outcomes for vehicle occupants are associated with the rollover of the vehicle, revealing the structural weakness of the steel pillars between windows, which must resist high levels of bending during rollovers. This study aims to reinforce these pillars with expired carbon fiber prepreg from the aircraft industry, improving safety and reducing environmental waste. To manufacture the pillars, shot-blasted hollow S275 steel tubes with a side length of 25 mm and a thickness of 1.5 mm were used. Bidirectional GG600T woven carbon fiber, CF, and aircraft-grade recycled carbon fiber-reinforced plastic, rCFRP, prepreg M21EV/IMA/3 were used as composite reinforcements. The first composite was made from a CF weave using the rigid epoxy resin Sicomin^® 8500/Sicomin^® SD8601. The rCFRP composite was frayed, and a new composite was made with the same rigid epoxy resin. Both composites were joined to the steel tube using a tough structural adhesive (SikaPower^® 1277). A third composite was obtained using the frayed rCFRP and the structural adhesive as a polymer matrix. All composites were treated with an APPT (atmospheric-pressure plasma torch) before being joined to the steel pillar with the structural adhesive. The comparison of the three reinforcements showed that the steel reinforced with the recycled prepreg composite manufactured with the rigid adhesive performed best, with a 50% increase in specific bending strength and only a 32% increase in weight. It also absorbed 71% more energy, which shows that this novel option for upcycling can noticeably increase the crashworthiness of structures.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643523/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837267","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":"Observation of Boson Peak of Fragile Baltic Amber Glass by Terahertz Time-Domain Spectroscopy.","authors":"Toru Sasaki, Soo Han Oh, Tatsuya Mori, Seiji Kojima","doi":"10.3390/ma17235956","DOIUrl":"10.3390/ma17235956","url":null,"abstract":"<p><p>Amber is a fragile (in Angell's classification) natural glass that has performed maturation processes over geological time. The terahertz dynamics of Baltic amber that was about 40 million years old were studied by terahertz time-domain spectroscopy (THz-TDS) in the frequency range of 0.2 and 6.0 THz. In general, the intensity of a boson peak is weak for fragile glass. In the terahertz transmission spectra of Baltic amber in the previous study, no boson peak was observed upon slow cooling. However, in the present study, upon rapid cooling down to 15 K, the boson peak was observed clearly at 0.36 THz by the suppression of ice nucleation of confined water. The dynamic correlation length determined by the boson peak frequency was compared with the static structure correlation length and the scale of the medium-range order as determined by the first sharp diffraction peak of X-ray diffraction (XRD) in the recent literature. It was found that the dynamic correlation length determined by THz-TDS was closely related to the static correlation length determined by the XRD analysis.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643011/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837441","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":"Phase Evolution in Mn_1.6Zn_0.2Ni_0.6Mg_0.2Al_0.4O₄ High-Entropy Oxide Films by Heat Treatment.","authors":"Wei Ren, Xianhai Liu, Wenting Wu, Weili Wang","doi":"10.3390/ma17235967","DOIUrl":"10.3390/ma17235967","url":null,"abstract":"<p><p>In this work, Mn-Zn-Ni-Mg-Al multi-layer films were annealed in air at different temperatures to form spinel-structured Mn_1.6Zn_0.2Ni_0.6Mg_0.2Al_0.4O₄ high-entropy oxide films. X-ray diffraction results demonstrate that the films possess a polycrystalline spinel phase as well as impurity phases: when annealed at 650 °C and 750 °C, MnO₂ and Al₂O₃ impurity phases exist; at 950 °C, an Al₂O₃ impurity phase exists. Only at 850 °C does a pure spinel phase exist. However, the film at 750 °C exhibits the best conductive behavior, which indicates that the impurity phases may not have to be removed to maintain the best electrical properties of the film.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643095/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837534","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":"The Influence of CLSM Magnification on the Measured Roughness of Differently Prepared Dental Materials.","authors":"Martin Rosentritt, Anne Schmutzler, Sebastian Hahnel, Laura Kurzendorfer-Brose","doi":"10.3390/ma17235954","DOIUrl":"10.3390/ma17235954","url":null,"abstract":"<p><p>This in vitro study investigated how varying magnifications (5×, 10×, 20×, and 50×) using a confocal laser scanning microscope (CLSM) influence the measured surface roughness parameters, R_a/S_a and R_z/S_z, of various materials with two surface treatments. Cylindrical specimens (d ≈ 8 mm, h ≈ 3 mm, <i>n</i> = 10) from titanium, zirconia, glass-ceramic, denture base material, and composite underwent diamond treatment (80 μm; wet) and polishing (#4000; wet; Tegramin-25, Struers, G). The surface roughness parameters (R_a/S_a, R_z/S_z) were measured with a CLSM (VK-100, Keyence, J) at 5×, 10×, 20×, and 50× magnifications. Line roughness (R_a/R_z) was measured along a 1000 μm distance in three parallel lines, while area roughness (S_a/S_z) was evaluated over a 2500 μm × 1900 μm area. The statistical analysis included ANOVA, the Bonferroni post hoc test, and Pearson correlation (SPSS 29, IBM, USA; α = 0.05). R_a/S_a and R_z/S_z showed significant differences (<i>p</i> ≤ 0.001, ANOVA) across magnifications, with values decreasing as magnification increased, highest at 5× and lowest at 50×. Titanium, zirconia, and glass-ceramic showed significant measured roughness values from 5× to 50×. Denture base material and composite had lower measured roughness values, especially after polishing. Line and area roughness varied significantly, indicating that magnification affects measured values. Standardizing magnifications is essential to ensure comparability between studies. A 50× magnification captures more detailed profile information while masking larger defects.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"17 23","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11643955/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837652","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}