CoatingsPub Date : 2024-09-11DOI: 10.3390/coatings14091170
Guohui Li, Shanjiao Wang, Fengming Du
{"title":"Investigation of the Flow Characteristics of Coated Slag during Continuous Casting","authors":"Guohui Li, Shanjiao Wang, Fengming Du","doi":"10.3390/coatings14091170","DOIUrl":"https://doi.org/10.3390/coatings14091170","url":null,"abstract":"During continuous casting, coated slag is applied to molten steel to enhance heat transfer and lubrication. In this study, a numerical calculation model was built to reveal the flowing characteristic of slag according to the fundamental principles of heat transfer and viscous fluid mechanics. The flow and heat transfer behaviour of protective slag on the surface of molten steel and the flow velocity of liquid slag in slag channel gaps were calculated and analyzed. The streaming and thermal conduction situation of slag on the surface of molten steel, as well as the flow velocity of liquid flux in the slag passage gap, were calculated and analyzed. The results showed that as the thickness of the liquidus slag film increased from 10 to 12 mm, the thermal flux density at the top of the flux film layer decreased from 0.1059 to 0.0882 MW/m2. The heat flux density increased rapidly within 0.1 m of the narrow side of the mould, reaching a peak value of 2.27 MW/m2. As the viscosity temperature factor of the flux increased from 0.45 to 2.05, the maximum floating speed of the liquid film from the water inlet to the narrow side in the centre district of the mould decreased from 0.0316 to 0.028 m/s, representing a reduction of approximately 11.4%. This study can provide a reference for the design and improvement of protective slag.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215932","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}
CoatingsPub Date : 2024-09-11DOI: 10.3390/coatings14091171
Kai Wang, Daliang Song, Likun Li, Guanghui Shao, Yingye Mi, Huiping Hu, Chuan Liu, Ping Tan
{"title":"Microstructure and Properties of CoCrFeNiTix High-Entropy Alloys Fabricated by Laser Additive Manufacturing","authors":"Kai Wang, Daliang Song, Likun Li, Guanghui Shao, Yingye Mi, Huiping Hu, Chuan Liu, Ping Tan","doi":"10.3390/coatings14091171","DOIUrl":"https://doi.org/10.3390/coatings14091171","url":null,"abstract":"CoCrFeNi HEAs have better ductility, while the strength and corrosion resistance need to be further improved, while metal materials for deep-sea operations put forward the requirement of excellent mechanical properties and very high corrosion resistance; however, CoCrFeNi HEAs have been less studied for the trade-off between mechanical properties and corrosion resistance. Therefore, the present study utilized the laser melting deposition (LMD) technique to fabricate a series of (CoCrFeNi)Tix (x = 0.2, 0.4, 0.6, 0.8, 1.0 at.%) HEAs and systematically investigated the influence of Ti content on the alloy’s microstructure, phase composition, mechanical properties, and electrochemical performance. The research findings revealed that as the Ti content increased, the alloy gradually transformed from a single face-centered cubic (FCC) phase to an FCC and body-centered cubic (BCC) dual-phase structure. The addition of Ti induced a transition in the alloy’s microstructure from an equiaxed to a dendritic morphology, accompanied by grain refinement. Energy dispersive spectroscopy analysis confirmed the uniform distribution of Ti within the alloy. The hardness of the alloy increased significantly with the increase in Ti content, reaching 804.5 HV when the Ti content was 1.0 at.%, which was 4.13 times higher than the Ti-free alloy. The tensile and compression test results showed that the (CoCrFeNi)Tix alloy with a Ti content of 0.4 at.% exhibited the best overall mechanical performance. The electrochemical test results indicated that the addition of Ti effectively enhanced the corrosion resistance of the alloy, with the 0.4 at.% Ti-containing alloy exhibiting the optimal corrosion resistance. This study provides a strong theoretical and experimental foundation for the design of high-performance CoCrFeNi-based HEAs.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215935","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}
CoatingsPub Date : 2024-09-11DOI: 10.3390/coatings14091176
Bin Zhang, Hongen Zhang, Qiang Ren, Bei He, Yi Zhang, Zhengwu Jiang
{"title":"Fabrication of Corrosion-Resistant Superhydrophobic Coatings and Impermeable Porous Structures Using Fluorinated Microemulsions Containing Thermally Decomposable Surfactants","authors":"Bin Zhang, Hongen Zhang, Qiang Ren, Bei He, Yi Zhang, Zhengwu Jiang","doi":"10.3390/coatings14091176","DOIUrl":"https://doi.org/10.3390/coatings14091176","url":null,"abstract":"In this work, a series of fluorinated microemulsions were synthesized using thermally decomposable N-dodecyl-N,N-dimethylamine N-oxide (LDAO) as surfactant. Then, polybutylene terephthalate nonwoven fabrics (PBT) were coated with microemulsion and heat-treated. Superhydrophobic and oil-repellent modified PBT with WCA (water contact angle) of about 152°, a sliding angle of about 2.1°, and oil repellency grade of 8 were prepared. The effect of surfactants on the surface wettability of hydrophobic materials was analyzed by TG-DTA, XPS, and WCA tests. The results show that surfactants decrease the WCA of hydrophobic materials, but LDAO can eliminate this effect by heat treatment. The anti-corrosion and permeability of LDAO coatings were compared with those of conventional fluorinated coatings through degradation and anti-permeability tests. It was shown that the LDAO fluorinated superhydrophobic coating is more resistant to corrosion by chemical solutions and significantly improves the impermeability of porous materials. Anti-fouling and self-cleaning tests showed excellent anti-fouling and self-cleaning properties on several common substrate surfaces modified with LDAO fluorinated microemulsions. It is expected that these new LDAO fluorinated microemulsions have promising applications in the preparation of corrosion-resistant surfaces and impermeable structures.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215938","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}
CoatingsPub Date : 2024-09-11DOI: 10.3390/coatings14091173
Hongfei Xu, Wenting Qu
{"title":"Development of a Controlled Low-Strength Material Containing Paraffin–Rice Husk Ash Composite Phase Change Material","authors":"Hongfei Xu, Wenting Qu","doi":"10.3390/coatings14091173","DOIUrl":"https://doi.org/10.3390/coatings14091173","url":null,"abstract":"In order to reduce heat loss and diffusion of underground heating pipelines, this research incorporated phase change material (PCM) into the controlled low-strength material (CLSM) to prepare a pipeline backfill material with temperature control performance. In response to the problem that PCM leaks easily, a new type of paraffin–rice husk ash composite PCM (PR-PCM) was obtained by adsorbing melted paraffin into rice husk ash. Through mixing PR-PCM with dredged sediment (DS) and ordinary Portland cement (OPC), a controlled low-strength material (CLSM) with temperature control performance was prepared. The flowability, mechanical properties, microscopic characteristics, thermal characteristics, and durability of CLSM were analyzed through flowability, unconfined compressive strength (UCS), X-ray diffraction (XRD), scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), and phase change cycle tests. The results show that when water consumption is constant, as the PR-PCM content increases, the flowability of CLSM increases, and the strength decreases. The CLSM has an obvious paraffin diffraction peak in the XRD pattern, and its microstructure is dense with few pores. The melting point of CLSM is 50.65 °C and the latent heat is 4.10 J/g. Compared with CLSM without PR-PCM, the maximum temperature difference during the heating process can reach 3.40 °C, and the heat storage performance is improved by 4.1%. The strength of CLSM increases and the melting point decreases after phase change cycles. CLSM containing PR-PCM has the characteristics of phase change temperature control, which plays a positive role in reducing heat loss by heating pipelines and temperature change in backfill areas.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215934","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 Multi-Physical Field Simulation of the Double-Glow Plasma Alloying Process Parameters","authors":"Lu Yu, Yiming Wen, Jindong Zhou, Yanzhao Qiu, Danning Yang, Hao Dai, Huilong Zhu, Zhiyuan Hu, Gongtao Liu, Aqib Mashood Khan, Hongyan Wu","doi":"10.3390/coatings14091175","DOIUrl":"https://doi.org/10.3390/coatings14091175","url":null,"abstract":"In order to study the coupling mechanism of the process parameters during the double-glow discharge process, and thus to enhance the theoretical study of double-glow plasma surface metallurgical technology, in this paper, a two-dimensional fluid model is established using COMSOL simulation software. The effects of key processing factors on the distribution of electrons and excited argon ions, potential and electron temperature in the coupling process of double-glow discharge were investigated. The results indicated that the electron density between the two electrode plates increases as the voltage difference increases. The optimal working pressure was kept between 0.14 Torr and 0.29 Torr. The optimal electrode spacing was between 15 mm and 30 mm and decreased with the increase in pressure. Compared with the actual plasma surface alloying process experiment, the simulation results were consistent with the experiments. The research can guide experiments by combining simulation and theory, and the predictability and accuracy of double-glow surface metallurgy technology have been improved.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215937","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}
CoatingsPub Date : 2024-09-09DOI: 10.3390/coatings14091165
Xiuyu Chen, Yalong Li, Longhui Li, Huanbin Xu, Yi Li, Zhilong Xu, Qingshan Jiang, Shixu Mu, Yin Li, Heng Liu
{"title":"The Effects of Different Ultrasonic Composite Surface Modifications on the Properties of H13 Steel for Shield Tunnel Machine Cutter Ring","authors":"Xiuyu Chen, Yalong Li, Longhui Li, Huanbin Xu, Yi Li, Zhilong Xu, Qingshan Jiang, Shixu Mu, Yin Li, Heng Liu","doi":"10.3390/coatings14091165","DOIUrl":"https://doi.org/10.3390/coatings14091165","url":null,"abstract":"Tunnel boring machines (TBMs) are exposed to the impact of the ground shattering force and the friction of sandstone during excavation work, and are prone to wear and breakage, and other failures. Traditional heat treatment processes cannot simultaneously achieve the required high-energy composite structure of hard external and tough internal properties for cutter rings, leading to inadequate wear resistance and impact toughness under working conditions. This study utilizes H13 steel as the base material, and based on a study of carburizing, nitriding, and ultrasonic impact processes for H13 steel analyzing the effects of different high-energy composite modification processes on the hardness distribution, microstructure, and residual stress of H13 steel, the mechanisms by which high-energy composite modification processes affect the wear resistance and impact resistance of H13 steel are revealed. The results indicate that the wear amount and impact toughness of the sample subjected to carburizing and ultrasonic surface rolling composite strengthening were 1.9 mg and 27.34 J/cm2, demonstrating the best wear and impact resistance. This combination of properties allows the H13 steel cutter ring to achieve the optimal overall performance in terms of wear resistance and impact resistance.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215944","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":"Assessment of Warionia saharea Essential Oil as a Green Corrosion Inhibitor for Mild Steel in HCl: Experimental and Computational Studies","authors":"Abdeslam Ansari, Youssef Youssefi, Mohamed Tanghourte, Nazih Ouassou, Nazih Asoufar, Mohamed Znini, Hassane Lgaz, El Houssine Mabrouk, Mohamed Azrour, Han-Seung Lee, Belkheir Hammouti","doi":"10.3390/coatings14091164","DOIUrl":"https://doi.org/10.3390/coatings14091164","url":null,"abstract":"The objective of this research work is the study of the inhibitory effect of Warionia saharea essential oil (WSEO) on the corrosion of mild steel (MS) in molar HCl solution, employing both experimental and theoretical methods. This inhibitory effect (IE) has been evaluated by using a combination of weight loss measurements (LW) and various electrochemical methods, such as open circuit potential (OCP), potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) experiments. The LW results indicated that IE increased with inhibitor concentration, reaching 83.34% at 3.00 g/L. The PDP analysis suggested that WSEO functions as a mixed inhibitor, while in the EIS results the Rct values increased with inhibitor concentration to reach 165.8 Ω cm2 at 2.00 g/L, suggesting a defensive film formation by WSEO molecules over the metallic surface. The thermodynamic study demonstrated that the WSEO molecules adsorption on the MS surface followed a Langmuir isotherm, involving mixed physical and chemical (physicochemical) adsorption on the MS surface. Theoretical methods, including density functional theory (DFT) and molecular dynamics (MD) simulations, were employed to elucidate the inhibition mechanisms of the three main components of WSEO. The quantum chemical analysis, using density functional theory (DFT) and molecular dynamics (MD) simulations, showed a low ΔEgap value of 6.30 eV and a low adsorption energy (Eads) value on an Fe (110) substrate of −258 Kcal/mol for (E)-Nerolidol, indicating the significant contribution of this molecule to the overall corrosion inhibition effect of WSEO. The scanning electron microscope (SEM) analysis verified the presence of a protective film formed by the inhibitor on the MS surface. This study highlights the potential of WSEO as a sustainable and green corrosion inhibitor in acidic environments.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215796","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}
CoatingsPub Date : 2024-09-09DOI: 10.3390/coatings14091161
Mengjiao Wang, Mingbo Zhu, Xinzheng Hu, Kun Liu, Xuefeng Fan, Xiangkai Meng, Xudong Peng, Jinqing Wang
{"title":"Synergistic Effect of Elliptic Textures and H-DLC Coatings for Enhancing the Tribological Performance of CuAl10Fe5Ni5 Valve Plate Surfaces","authors":"Mengjiao Wang, Mingbo Zhu, Xinzheng Hu, Kun Liu, Xuefeng Fan, Xiangkai Meng, Xudong Peng, Jinqing Wang","doi":"10.3390/coatings14091161","DOIUrl":"https://doi.org/10.3390/coatings14091161","url":null,"abstract":"Axial piston pumps with compact structures and high efficiency are widely used in construction machinery. The efficiency and lifetime strongly depend on the tribological performance of the pump’s valve plate pair. To enhance the tribological performance of the valve plate pair, surface textures, and H-DLC coatings were fabricated to modify the CuAl10Fe5Ni5 surfaces. The influences of elliptic textures of different sizes and textured H-DLC coatings on the surface friction and wear properties of the valve plate surface under oil lubrication were evaluated using a ring-on-disk tribometer. The results reveal that the friction and wear properties of the CuAl10Fe5Ni5 surfaces are significantly enhanced by elliptic textures, and the friction coefficient and wear rate of textured CuAl10Fe5Ni5 with E90 are maximally decreased by 95% and 87%, respectively. Compared with the surface textures and H-DLC coatings, the textured H-DLC coating has the greatest ability to reduce wear and adhesion. The wear rate of the textured H-DLC coating is further reduced by 98%. This improvement can be explained by the synergistic effect of the elliptic textures and H-DLC coatings, which are attributed to the reduced contact area, debris capture, and secondary lubrication of the elliptic textures, and increased surface hardness.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215942","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}
CoatingsPub Date : 2024-09-09DOI: 10.3390/coatings14091158
Minseong Bae, Seongki Ahn, Sunkyung You, Jae-kwang Kim, Daewon Kim, Hanjoo Kim, Hong-Il Kim, Jinjoo Park
{"title":"Expanded Illite Filler in UV-Curable Polymer Electrolytes for All-Solid-State Li-Ion Batteries","authors":"Minseong Bae, Seongki Ahn, Sunkyung You, Jae-kwang Kim, Daewon Kim, Hanjoo Kim, Hong-Il Kim, Jinjoo Park","doi":"10.3390/coatings14091158","DOIUrl":"https://doi.org/10.3390/coatings14091158","url":null,"abstract":"In this study, we explored the potential of illite sourced from Yeongdong-eup, South Korea, as a filler in polymer electrolytes for all-solid-state Li-ion batteries. The illite was expanded (EI) by acid treatment and UV curing was employed to synthesize the polymer electrolytes. The Li+ ionic conductivity of the polymer electrolytes was measured at various EI contents, revealing the highest conductivity of 1.08 × 10−2 S cm−1 at 4 wt% of the EI. The electrochemical performance of NMC cells assembled with the EI-incorporated polymer electrolyte showed a good discharge capacity of over 158.6 mAh g−1 with a coulombic efficiency of 99%. These findings demonstrate the significant potential of EI as a sustainable and efficient filler material for enhancing the performance of polymer-based all-solid-state Li batteries. This study highlighted the applicability of illite sourced from South Korea and its potential contribution to the development of polymer-based all-solid-state batteries.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215939","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}
CoatingsPub Date : 2024-09-09DOI: 10.3390/coatings14091160
Jiewen Wang, Jun Li, Lina Tang, Taotao Wu, Xin Liu, Yixue Wang
{"title":"Theoretical Calculations and Experimental Study of the Nitrided Layer of 1Cr17Ni2 Steel","authors":"Jiewen Wang, Jun Li, Lina Tang, Taotao Wu, Xin Liu, Yixue Wang","doi":"10.3390/coatings14091160","DOIUrl":"https://doi.org/10.3390/coatings14091160","url":null,"abstract":"Due to the harsh operating conditions experienced by 1Cr17Ni2 steel, efforts were made to optimize its performance by subjecting 1Cr17Ni2 stainless steel to nitriding treatments at temperatures of 460 °C, 500 °C, and 550 °C, each for durations of 8 and 16 h. The formation state of its cross section was observed through a metallurgical microscope and scanning electron microscope, and it was characterized by hardness measurement. Through a ball-on-disk wear experiment, the adhesive wear and friction coefficient of its non-lubricated sliding were measured. The phase composition of its surface was measured by XRD. The results revealed that nitriding led to the formation of a modified layer on the surface of the samples, with a depth of 130 μm after nitriding at 550 °C for 16 h. The hardness of the modified layer exceeded that of the matrix, reaching up to 1400 Hv0.1. X-ray diffraction (XRD) analysis of the sample surfaces indicated the presence of high-hardness phases such as CrN, γ′-Fe4N, and ε-Fe2-3N. This article predicts the mechanical properties of nitrided phases in high-alloy martensitic stainless steel through first-principles computational methods. We provide a reference for improving the performance of high-alloy steel after nitriding through a combination of theoretical calculations and experiments.","PeriodicalId":10520,"journal":{"name":"Coatings","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215941","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}