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Surface tribological and electrochemical properties of TiAlSiN coating in seawater TiAlSiN涂层在海水中的表面摩擦学和电化学性能
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-31 DOI: 10.1088/2051-672X/acda4c
A. Liu, J. Deng, Runzhou Tian
To investigate the effects of friction surface and electrochemical properties on the tribological behavior of TiAlSiN coatings in seawater, the tribological properties of TiAlSiN coatings in air and seawater are comparatively studied using a ball-on-disk tribometer with Si3N4 ceramic balls as the counter material. The results show that under both friction conditions, the wear rate of TiAlSiN coating is decreased compared with 316 l steel substrate, and the coating presents a good protective effect. When friction occurs in air, the abrasive debris in the wear area cannot be discharged in time, resulting in the accumulation of abrasive debris and accelerating the wear of the coating. When friction occurs in seawater, although seawater is corrosive, the lubricating barrier surface formed by the friction oxide during the friction process significantly reduces the wear rate of the coating. In addition, the excellent electrochemical properties and the dense coating microstructure improve the tribocorrosion resistance of the TiAlSiN coating in seawater. It proves that friction surface has a great impact on the tribological performance of TiAlSiN coatings, and how to form a more favorable friction layer in the tribochemical environment is worthy of further research in the field of marine equipment.
为了研究摩擦表面和电化学性能对TiAlSiN涂层在海水中的摩擦学性能的影响,采用以氮化硅陶瓷球为反相材料的球盘式摩擦计,比较研究了TiAlSiN涂层在空气和海水中的摩擦学性能。结果表明:在两种摩擦条件下,TiAlSiN涂层的磨损率均低于316l钢基体,涂层具有良好的防护效果;当空气中发生摩擦时,磨损区的磨粒不能及时排出,造成磨粒堆积,加速涂层的磨损。当在海水中发生摩擦时,虽然海水具有腐蚀性,但摩擦过程中由摩擦氧化物形成的润滑屏障表面显著降低了涂层的磨损率。此外,优异的电化学性能和致密的涂层组织提高了TiAlSiN涂层在海水中的耐摩擦腐蚀性能。证明摩擦表面对TiAlSiN涂层的摩擦学性能有很大的影响,如何在摩擦化学环境中形成更有利的摩擦层是值得在海洋装备领域进一步研究的问题。
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引用次数: 0
A measure of perceived quality to secure the polishability of new paint systems 确保新涂料系统可抛光性的一种可感知质量的度量
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-24 DOI: 10.1088/2051-672X/acd869
S. Rebeggiani, B. Rosén
The automotive industry continuously strives to reduce their environmental impact. For the paint shop it means to introduce more sustainable paint concepts, while maintaining the production rate and retain the right surface appearance that is crucial for the vehicle’s perceived quality. Today most painted parts are visually inspected and, if needed, manually repaired by abrasive polishing to eliminate spot defects. The repair process consists of one sanding step to remove the defect, and one or two rubbing/polishing steps to restore the surface, but still it tends to be a non-reliable process leaving patterns or clusters of shallow micro scratches seen as three-dimensional shapes moving over the surface when viewed from different angles like holograms. These so called ‘polishing roses’ are hard to detect in artificial light but clearly visible in Sunlight and therefore they constitute a constant quality issue. Accurate polishing procedures in combination with more objective inspection techniques would secure a high surface quality—but what is ‘accurate’? The overall scope of the study was to deepen the knowledge of paint systems to develop test routines for the polishability of coatings already during the development stage, and thereby ease the implementation of new coating systems in production. The study was based on collected process data from professional polishers to define a process window based on key parameters for successful end-of-line repairs of coated surfaces, i.e. strategies minimizing the occurrence of visible polishing traces. A CNC-machine was built up for the purpose to systematically test and evaluate new coating systems and repair procedures. The surface estimation was made by visual inspections as well as by a further developed photometric stereo system providing quantitative images of remaining repair traces.
汽车工业一直在努力减少对环境的影响。对于油漆车间来说,这意味着引入更可持续的涂料概念,同时保持生产率和保持正确的表面外观,这对车辆的感知质量至关重要。今天,大多数涂漆的部件都是目视检查的,如果需要,还可以通过磨料抛光手工修复,以消除斑点缺陷。修复过程包括一个磨砂步骤,以消除缺陷,一个或两个摩擦/抛光步骤,以恢复表面,但这仍然是一个不可靠的过程,留下图案或簇浅微划痕,当从不同的角度观察时,就像全息图一样,在表面上移动的三维形状。这些所谓的“抛光玫瑰”在人造光下很难发现,但在阳光下却清晰可见,因此它们构成了一个持续的质量问题。精确的抛光程序与更客观的检查技术相结合将确保高表面质量-但什么是“精确”?研究的总体范围是加深对涂料系统的了解,在开发阶段为涂料的可抛光性制定测试程序,从而简化新涂料系统在生产中的实施。该研究基于从专业抛光师那里收集的工艺数据,根据成功修复涂层表面的关键参数定义工艺窗口,即最小化可见抛光痕迹的策略。为了系统地测试和评估新的涂层系统和修复程序,建立了一台数控机床。表面估计是通过目视检查和进一步发展的光度立体系统,提供剩余修复痕迹的定量图像。
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引用次数: 0
Characterization of aperiodic surfaces with mesh-based parameters 基于网格参数的非周期曲面表征
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-24 DOI: 10.1088/2051-672X/acd868
Stefanie Stöckel, F. Segel, Sophie Groeger
For technical surfaces, it is important to know their functional purpose and to characterize them accordingly. Therefore, ISO 21920–2 in 2D and ISO 25178–2 in 3D offer parameters that can assess surface functional properties. The topographic portions of a surface, for example hills and dales, can be classified as features and evaluated using feature parameters. However, no parameter exists to describe the spatial distribution of features with regard to the degree of homogeneity for aperiodic surfaces. Here we show the application of the Delaunay triangulation to quantify the spatial distribution respectively the geometric relationship of features. Therefore, the feature points are determined by watershed analysis and the resulting point cloud is meshed in 2D. Based on that mean and standard deviation of the triangle side lengths and the area disorder (AD) are calculated as new parameters. The method is demonstrated for sandblasted and chrome-plated specimens. In addition simulation is used to generate more data for analysis. With the proposed approach the distinction and extent of uniform, homogeneous or inhomogeneous spatial distributions of features with parameter AD can be determined.
对于技术表面,重要的是要知道它们的功能目的,并相应地表征它们。因此,2D的ISO 21920-2和3D的ISO 25178-2提供了可以评估表面功能特性的参数。表面的地形部分,例如丘陵和山谷,可以分类为特征并使用特征参数进行评估。然而,对于非周期曲面,没有参数来描述特征在均匀度方面的空间分布。在这里,我们展示了Delaunay三角剖分法的应用,分别量化了特征的空间分布和几何关系。因此,通过分水岭分析确定特征点,并将得到的点云进行二维网格划分。在此基础上,计算了三角形边长的均值、标准差和面积无序度作为新的参数。该方法对喷砂和镀铬试样进行了验证。此外,还使用仿真来生成更多的分析数据。利用该方法可以确定具有AD参数的特征的均匀、均匀或非均匀空间分布的区别和程度。
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引用次数: 0
Influence of contact angle on droplet parameters in ellipsoidal wettability model 椭球润湿性模型中接触角对液滴参数的影响
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-19 DOI: 10.1088/2051-672X/acd70a
Zehua Xu, Yanbin Zhang, Xiaosen Wang, Kangshuai Li, Qiang He
Contact angle is one of the most important indexes to evaluate the hydrophobicity of solid surface. In order to explore the wetting characteristics of droplets on anisotropic solid surfaces, including contact angle, droplet radius, droplet height, contact radius, contact area and projected area, an ellipsoidal droplet contact angle model was established. Different from the ordinary plane ellipsoidal cap model, the major axis and minor axis of the elliptical cap shape in this model are not exactly the same in different planes. This model studied the relationship between contact angle and interface parameters in different planes. By collecting the droplet size parameters of fluororubber (FKM) prepared by template method, the correctness of the theoretical model was verified. Among them, the maximum error between the theoretical value of droplet radius and the actual measured value was 4.3%, and the maximum error of droplet projected area was 2.1%. It was found that the contact angle was inversely proportional to the droplet-solid contact radius and contact area, and directly proportional to the projected area of the droplet. In addition, for the same droplet on the surface of the same solid material, it was observed that the contact radius between the droplet and the solid was small in the direction of large contact angle. This discovery is helpful to explain the hydrophobic mechanism of the material surface with anisotropic contact angle.
接触角是评价固体表面疏水性的重要指标之一。为了探讨液滴在各向异性固体表面上的润湿特性,包括接触角、液滴半径、液滴高度、接触半径、接触面积和投影面积,建立了椭球状液滴接触角模型。与普通平面椭球帽模型不同,该模型中椭球帽形状的长、短轴在不同平面上并不完全相同。该模型研究了接触角与界面参数在不同平面上的关系。通过收集模板法制备的氟橡胶(FKM)的液滴尺寸参数,验证了理论模型的正确性。其中液滴半径理论值与实际测量值的最大误差为4.3%,液滴投影面积的最大误差为2.1%。结果表明,接触角与液滴-固体接触半径和接触面积成反比,与液滴投影面积成正比。此外,对于同一固体材料表面上的同一液滴,观察到在大接触角方向上,液滴与固体的接触半径较小。这一发现有助于解释具有各向异性接触角的材料表面的疏水机理。
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引用次数: 0
A review on TIG cladding of engineering material for improving their surface property TIG包覆改善工程材料表面性能的研究进展
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-18 DOI: 10.1088/2051-672X/acd6aa
K. Biswas, C. Sahoo
Different components used in industries like power plant, petrochemical, automobile are subjected to severe wear and corrosion due to high temperature and pressure environments. Therefore, it is necessary to improve those components’ wear and corrosion resistance properties. Different processes like laser cladding, CVD, PVD, and thermal spraying are widely used for upgrading surface properties of material. In recent days, it has been found that many researchers investigated the performance of tungsten inert gas (TIG) welding for cladding of superior material like ceramics, metal etc on different substrate materials. TIG cladding can fulfil the requirements of industries by developing a quality cladded layer with low cost and high productivity. This research paper has made an effort to compile the literature related to TIG cladding process for improving substrate properties. It has been observed that the superior materials like titanium carbide(TiC), silicon carbide(SiC), tungsten carbide(WC), cobalt-based alloys, and nickel-based alloys have been successfully cladded using TIG welding process. Researchers have also observed adequate improvement in properties like microhardness and wear resistance of different grades of steel substrate material, like 304, 316 stainless steel, 1010, and 1020 low-carbon steel. The process is also successfully utilized for cladding of superior material on nonferrous metals like Al, Ti alloy. The TIG clad quality and performance rely on different process parameters like current, scan speed, and shielding gas flow rate and also the properties of coating and substrate material.
在电厂、石化、汽车等行业中使用的不同部件由于高温高压环境而受到严重的磨损和腐蚀。因此,有必要提高这些部件的耐磨损和耐腐蚀性能。激光熔覆、CVD、PVD和热喷涂等工艺被广泛用于提高材料的表面性能。近年来,许多研究者对陶瓷、金属等优良材料在不同衬底材料上熔覆钨极惰性气体(TIG)焊的性能进行了研究。TIG熔覆可以开发出低成本、高生产率的高质量熔覆层,满足工业生产的要求。本论文对TIG包覆工艺改善基板性能的相关文献进行了整理。采用TIG焊工艺成功地熔覆了碳化钛(TiC)、碳化硅(SiC)、碳化钨(WC)、钴基合金和镍基合金等优良材料。研究人员还观察到,不同等级的钢基体材料,如304、316不锈钢、1010和1020低碳钢,在显微硬度和耐磨性等性能上有了充分的改善。该工艺还成功地应用于铝、钛合金等有色金属的优质材料包覆。TIG包层的质量和性能取决于不同的工艺参数,如电流、扫描速度、保护气体流量以及涂层和衬底材料的性能。
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引用次数: 0
Influence of tool pin profiles on waviness and natural frequency during friction stir welding of Al-Li alloys plates 刀销轮廓对铝锂合金板搅拌摩擦焊波形和固有频率的影响
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-16 DOI: 10.1088/2051-672X/acd5ea
Sanjeev Kumar, Ashish Soni, J. Katiyar, Sachin Kumar, B. S. Roy
The third generation of Al-Li 2050-T84 alloy was primarily used in aerospace industries due to its exceptional potential for weight saving, high strength, and increased fatigue crack growth resistance. In the present research, three different types of tool pin profiles, namely, hybrid, taper threaded, and triangular, were used to join 2050-T84 Al-Li alloy by using Friction Stir Welding (FSW) at a constant rotational speed of 23.33 rotation/second with a traverse speed of 0.003 meters per second and tilt angle of 2°. The research explored the effect of different tools on weld bead structure, waviness and natural frequency of welded plates. The experimental results show that the hybrid tool pin side generates 10.9% higher heat than the threaded taper tool and 25.8% higher than the triangular tool. Moreover, the hybrid tool produces 50.1% lower waviness of welded specimens than the threaded taper tool and 55.7% lower than the triangular tool at the nugget zone (NZ). The research established that a hybrid tool pin profile is advantageous as it generates a higher frequency and lower acceleration under the applied load in friction stir welded specimens.
第三代Al-Li 2050-T84合金主要用于航空航天工业,因为它具有减重、高强度和抗疲劳裂纹增长的特殊潜力。在恒转速为23.33转/秒、横移速度为0.003米/秒、倾斜角度为2°的搅拌摩擦焊接(FSW)条件下,采用混合、锥螺纹和三角形三种不同类型的工具销型连接2050-T84铝锂合金。研究了不同工具对焊接板焊缝结构、波纹度和固有频率的影响。实验结果表明,混合刀销侧产生的热量比螺纹锥刀高10.9%,比三角刀高25.8%。混合刀具在熔核区(NZ)的波纹度比螺纹锥刀具低50.1%,比三角形刀具低55.7%。研究表明,混合刀销型在搅拌摩擦焊试样载荷作用下具有较高的频率和较低的加速度等优点。
{"title":"Influence of tool pin profiles on waviness and natural frequency during friction stir welding of Al-Li alloys plates","authors":"Sanjeev Kumar, Ashish Soni, J. Katiyar, Sachin Kumar, B. S. Roy","doi":"10.1088/2051-672X/acd5ea","DOIUrl":"https://doi.org/10.1088/2051-672X/acd5ea","url":null,"abstract":"The third generation of Al-Li 2050-T84 alloy was primarily used in aerospace industries due to its exceptional potential for weight saving, high strength, and increased fatigue crack growth resistance. In the present research, three different types of tool pin profiles, namely, hybrid, taper threaded, and triangular, were used to join 2050-T84 Al-Li alloy by using Friction Stir Welding (FSW) at a constant rotational speed of 23.33 rotation/second with a traverse speed of 0.003 meters per second and tilt angle of 2°. The research explored the effect of different tools on weld bead structure, waviness and natural frequency of welded plates. The experimental results show that the hybrid tool pin side generates 10.9% higher heat than the threaded taper tool and 25.8% higher than the triangular tool. Moreover, the hybrid tool produces 50.1% lower waviness of welded specimens than the threaded taper tool and 55.7% lower than the triangular tool at the nugget zone (NZ). The research established that a hybrid tool pin profile is advantageous as it generates a higher frequency and lower acceleration under the applied load in friction stir welded specimens.","PeriodicalId":22028,"journal":{"name":"Surface Topography: Metrology and Properties","volume":"160 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2023-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79852726","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}
引用次数: 0
Stratified topography theory to understand frictional electrification for sliding triboelectric nanogenerators 用层状地形理论来理解滑动摩擦电纳米发电机的摩擦起电作用
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-16 DOI: 10.1088/2051-672X/acd5eb
Haoran Li, Tianyu Han, Huihui Hu, Xi Shi, Zhilong Peng, Songtao Hu
Researchers are used to investigating the influence of surface topography on the frictional electrification of sliding triboelectric nanogenerators TENGs from the perspective of a single-stratum topography; however, a stratified feature has shared reality in closer relationships. Here, we characterize the stratified feature of the topographies for the sliding TENGs, and link them to the electrification voltages, finding that the frictional electrification strongly depends on the characteristics of the small-scale component in a stratified topography, which suggest us to develop a stratified electrification model for mechanism reveal. Based on the dependence, we also succeed in identifying the stratified topographic characteristics with frictional electrification signals by machine learning including support vector machine and convolutional neural network, which can be envisioned as a tool for topography measurement. This is the first demonstration of a stratified topography theory for sliding TENGs, providing new insights into the mechanism reveal and functional application of frictional electrification.
研究人员习惯于从单一地层地形的角度研究表面地形对滑动摩擦电纳米发电机摩擦起电的影响;然而,一个分层的特征在更亲密的关系中共享现实。在这里,我们描述了滑动teng的地形分层特征,并将其与电气化电压联系起来,发现摩擦电气化强烈依赖于分层地形中小尺度组件的特征,这表明我们需要建立分层电气化模型来揭示机理。基于这种依赖关系,我们还成功地通过支持向量机和卷积神经网络等机器学习方法识别了摩擦电气化信号的分层地形特征,这可以作为地形测量的工具。这是第一次展示了滑动teng的分层地形理论,为摩擦电气化的机制揭示和功能应用提供了新的见解。
{"title":"Stratified topography theory to understand frictional electrification for sliding triboelectric nanogenerators","authors":"Haoran Li, Tianyu Han, Huihui Hu, Xi Shi, Zhilong Peng, Songtao Hu","doi":"10.1088/2051-672X/acd5eb","DOIUrl":"https://doi.org/10.1088/2051-672X/acd5eb","url":null,"abstract":"Researchers are used to investigating the influence of surface topography on the frictional electrification of sliding triboelectric nanogenerators TENGs from the perspective of a single-stratum topography; however, a stratified feature has shared reality in closer relationships. Here, we characterize the stratified feature of the topographies for the sliding TENGs, and link them to the electrification voltages, finding that the frictional electrification strongly depends on the characteristics of the small-scale component in a stratified topography, which suggest us to develop a stratified electrification model for mechanism reveal. Based on the dependence, we also succeed in identifying the stratified topographic characteristics with frictional electrification signals by machine learning including support vector machine and convolutional neural network, which can be envisioned as a tool for topography measurement. This is the first demonstration of a stratified topography theory for sliding TENGs, providing new insights into the mechanism reveal and functional application of frictional electrification.","PeriodicalId":22028,"journal":{"name":"Surface Topography: Metrology and Properties","volume":"10 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2023-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86544063","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}
引用次数: 0
Wear behavior of ceramic, composite, and ceramic/composite interfaces 陶瓷、复合材料和陶瓷/复合材料界面的磨损行为
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-16 DOI: 10.1088/2051-672X/acd5e9
Elif Sevilay Yıldırım, N. Tekçe, S. Fidan, S. Tuncer, M. Demirci
Objective. This study has aimed to evaluate the effects of toothbrushing on the wear behavior of two composites, three ceramic materials, and ceramic/composite interfaces. Material and Methods. Nanofilled (Filtek Ultimate), and nanohybrid composites (Spectra ST HV) were used for the repair of a hybrid ceramic (Vita Enamic), resin nanoceramic (Katana Avencia), and zirconia block (Katana Zirconia). Composites, ceramics, and ceramic/composite interfaces were examined before and after a period of one-month and one-year of toothbrush abrasion testing using non-contact optical profilometry and scanning electron microscopy (SEM). Data were analyzed by two-way ANOVA and Bonferroni correction. The statistical significance level was set at p < 0.05. Results. No difference was found between the surface roughness of the Vita Enamic, Katana Avencia, Filtek Ultimate, and Spectra surfaces after one month and one year of toothbrushing. Sa values in Katana Zirconia material were found to be significantly lower than those in the control group after one year of brushing. The surface roughness of the repair interfaces formed by repairing hybrid ceramic and resin nanoceramic CAD/CAM materials with nanofilled and nanohybrid composite materials was found to be similar after different brushing times. Conclusion. Vita Enamic, Katana Avencia, Filtek Ultimate, and Spectra materials can be preferred in clinical repair applications, since they exhibit similar wear behavior after brushing at different times. For the zirconia material, the repair interface had similar surface roughness as the ceramic and composite surfaces after one year of brushing. Periodic recalls and re-polishing may thus be necessary when these products are used clinically.
目标。本研究旨在评估刷牙对两种复合材料、三种陶瓷材料和陶瓷/复合材料界面磨损行为的影响。材料和方法。纳米填充(Filtek Ultimate)和纳米混合复合材料(Spectra ST HV)用于修复混合陶瓷(Vita Enamic)、树脂纳米陶瓷(Katana Avencia)和氧化锆块(Katana zirconia)。使用非接触式光学轮廓术和扫描电子显微镜(SEM)对复合材料、陶瓷和陶瓷/复合材料界面进行为期一个月和一年的牙刷磨损测试前后的检查。数据分析采用双向方差分析和Bonferroni校正。差异有统计学意义,p < 0.05。结果。Vita Enamic、Katana Avencia、Filtek Ultimate和Spectra的表面粗糙度在刷牙一个月和一年之后没有差异。经过一年的刷牙,发现Katana氧化锆材料中的Sa值明显低于对照组。采用纳米填充材料和纳米复合材料对杂化陶瓷和树脂纳米陶瓷CAD/CAM材料进行修复后,修复界面的表面粗糙度在不同的涂刷次数下是相似的。结论。Vita Enamic, Katana Avencia, Filtek Ultimate和Spectra材料在临床修复应用中是首选,因为它们在不同时间刷牙后表现出相似的磨损行为。对于氧化锆材料,经过一年的涂刷后,修复界面的表面粗糙度与陶瓷和复合材料表面相似。因此,当这些产品在临床上使用时,可能需要定期召回和重新抛光。
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引用次数: 0
Study of the surface roughness and optimization of machining parameters during laser-assisted fast tool servo machining of glass-ceramic 激光辅助快速伺服刀具加工玻璃陶瓷表面粗糙度及加工参数优化研究
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-16 DOI: 10.1088/2051-672X/acd5ec
Mingxu Fan, Xiaoping Zhou, Shunfa Chen, Shan Jiang, Jinzhou Song
Glass-ceramic is a typical hard and brittle material that is difficult to machine. In order to improve the surface quality of laser-assisted fast tool servo machining optical free-form surface of glass-ceramic, the effects of spindle speed, feed speed, piezoelectric frequency and laser power on the surface roughness were investigated. Firstly, the Taguchi method (TM) was used to establish the orthogonal experiment, and the contribution rate of each machining parameter to the surface roughness was obtained through variance and signal-to-noise ratio (S/N) analysis. The order of the influence degree of each parameter on the surface roughness is as follows: laser power > spindle speed > feed speed > piezoelectric frequency. The optimal machining parameter combinations obtained for the TM experiment are as follows: spindle speed 50 rpm, feed speed 0.01 mm rev−1, piezoelectric frequency 8 Hz, laser power 75 W. The range of surface roughness reduction obtained by comparing laser-assisted machining (LAM) with pure fast tool servo (FTS) machining is 38.75%∼58.77%. The Box-Behnken Design (BBD) in response surface methodology (RSM) was used to design experiments and a regression model for surface roughness was established through RSM. The deviation between the surface roughness predicted by the regression equation and the experimental value is less than ±6%. The influence law of various machining parameters on surface roughness was studied through three-dimensional response surface. RSM optimized the minimum surface roughness with a desirability of 99.43%. The optimal combination of machining parameters optimized through RSM is as follows: spindle speed 53.71 rpm, feed speed 0.02 mm rev−1, piezoelectric frequency 6.73 Hz, laser power 72 W. This paper is the first to combine LAM with FTS for machining optical free-form surface of glass-ceramic. This study provides a reference for laser-assisted fast tool servo machining and the research methods of surface quality.
玻璃陶瓷是一种典型的硬脆材料,难以加工。为了提高激光辅助快速刀具伺服加工玻璃陶瓷光学自由曲面的表面质量,研究了主轴转速、进给速度、压电频率和激光功率对表面粗糙度的影响。首先,采用田口法(Taguchi method, TM)建立正交试验,通过方差分析和信噪比(S/N)分析得到各加工参数对表面粗糙度的贡献率;各参数对表面粗糙度的影响程度依次为:激光功率>主轴转速>进给转速>压电频率。TM实验得到的最佳加工参数组合为:主轴转速50 rpm,进给速度0.01 mm rev−1,压电频率8 Hz,激光功率75 W。通过比较激光辅助加工(LAM)与纯快速刀具伺服(FTS)加工获得的表面粗糙度降低范围为38.75% ~ 58.77%。采用响应面法(RSM)中的Box-Behnken设计(BBD)进行试验设计,并通过响应面法建立了表面粗糙度的回归模型。回归方程预测的表面粗糙度与实验值的偏差小于±6%。通过三维响应面研究了不同加工参数对表面粗糙度的影响规律。RSM优化后的最小表面粗糙度可达99.43%。通过RSM优化的加工参数最优组合为主轴转速53.71 rpm,进给转速0.02 mm rev−1,压电频率6.73 Hz,激光功率72 W。本文首次将LAM与FTS相结合用于玻璃陶瓷光学自由曲面的加工。该研究为激光辅助快速刀具伺服加工及表面质量的研究方法提供了参考。
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引用次数: 1
Effect of special-shaped texture on tribological properties of PTFE-based friction material/CuSn6 friction pair 异形织构对ptfe基摩擦材料/CuSn6摩擦副摩擦学性能的影响
IF 2.7 3区 材料科学 Q2 ENGINEERING, MECHANICAL Pub Date : 2023-05-15 DOI: 10.1088/2051-672X/acd56b
Zeng Shuaishuai
In this paper, special-shaped textures with different sizes and densities were fabricated on the surface of CuSn6 by laser, and the friction and wear properties were tested by a multifunctional friction and wear tester. The experimental results show that different friction coefficients can be obtained in the vertical and inclined planes of the special-shaped texture. When the special-shaped texture size is 600 μm, the friction coefficient ring increases gradually with the increase of special-shaped texture density. The wear loss of Polytetrafluoroethylene (PTFE) based friction materials decreases gradually, effectively improving the wear resistance of PTFE-based friction materials.
利用激光在CuSn6表面制备了不同尺寸和密度的异形织构,并利用多功能摩擦磨损试验机对其摩擦磨损性能进行了测试。实验结果表明,在异形织构的垂直和斜面上可以获得不同的摩擦系数。当异形织构尺寸为600 μm时,随着异形织构密度的增加,摩擦系数环逐渐增大。聚四氟乙烯(PTFE)基摩擦材料的磨损损耗逐渐减小,有效提高了聚四氟乙烯基摩擦材料的耐磨性。
{"title":"Effect of special-shaped texture on tribological properties of PTFE-based friction material/CuSn6 friction pair","authors":"Zeng Shuaishuai","doi":"10.1088/2051-672X/acd56b","DOIUrl":"https://doi.org/10.1088/2051-672X/acd56b","url":null,"abstract":"In this paper, special-shaped textures with different sizes and densities were fabricated on the surface of CuSn6 by laser, and the friction and wear properties were tested by a multifunctional friction and wear tester. The experimental results show that different friction coefficients can be obtained in the vertical and inclined planes of the special-shaped texture. When the special-shaped texture size is 600 μm, the friction coefficient ring increases gradually with the increase of special-shaped texture density. The wear loss of Polytetrafluoroethylene (PTFE) based friction materials decreases gradually, effectively improving the wear resistance of PTFE-based friction materials.","PeriodicalId":22028,"journal":{"name":"Surface Topography: Metrology and Properties","volume":"47 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2023-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78975529","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}
引用次数: 0
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Surface Topography: Metrology and Properties
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