Lubricants最新文献_第5页

Effect of Oil Dispersion on Lubricating Film Thickness Generation under Oil Droplet Supply Conditions 油滴供给条件下润滑油分散对润滑油膜厚度生成的影响

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-12-03 DOI: 10.3390/lubricants11120512

Chenglong Liu, Wei Li, Feng Guo, P. Wong, Xinming Li

引用次数: 0

Self-Lubricating Properties of Polyether-Ether-Ketone Composites Filled with CNTs@RC2540 Nano-Capsules 填充 CNT@RC2540 纳米胶囊的聚醚-醚-酮复合材料的自润滑性能

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-12-01 DOI: 10.3390/lubricants11120511

Jiju Guan, Zhengya Xu, Lei Zheng, Lanyu Yang, Shuiquan Huang

{"title":"Self-Lubricating Properties of Polyether-Ether-Ketone Composites Filled with CNTs@RC2540 Nano-Capsules","authors":"Jiju Guan, Zhengya Xu, Lei Zheng, Lanyu Yang, Shuiquan Huang","doi":"10.3390/lubricants11120511","DOIUrl":"https://doi.org/10.3390/lubricants11120511","url":null,"abstract":"Polyether-ether-ketone (PEEK) exhibits great potential in being a replacement for metal components across various applications relying on the mechanical and tribological properties. However, there is still much to be done to improve its properties. The main motivation of this paper is to improve the tribological and mechanical properties of PEEK simultaneously for more severe working environment. Therefore, dialkyl pentasulfide (RC2540) was proposed to fill into the cavity of CNTs to prepare nano-capsules, which were then filled into PEEK to prepare PEEK/nano-capsules composites. The existence of nano-capsules in PEEK was analyzed, and the friction and wear properties exhibited by PEEK composites against GCr15 steel were examined using pin-disk friction pairs, and the self-lubricating mechanism of PEEK composites in friction was revealed. Findings of this study indicated that when the mass fraction of nano-capsules was less than 5%, the filling of nano-capsules could improve the tensile strength of PEEK and reduced the friction coefficient and specific wear rate of PEEK by filling nano-capsules. During the friction process, RC2540 in the nano-capsules can be released as PEEK wears so that a self-lubricating layer can be formed for reducing PEEK composites’ friction and wear.","PeriodicalId":18135,"journal":{"name":"Lubricants","volume":" February","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138611152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental Study of Piezoelectric Control for Changing Tilting Pad Journal Bearing Circumferential Angle and Radial Displacement 压电控制改变斜垫式轴颈轴承圆周角和径向位移的实验研究

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-12-01 DOI: 10.3390/lubricants11120510

Shuxia Peng, Xin Qin, Xiaojing Wang, Guangyao Huang, Xin Xiong

引用次数: 0

Analysis, Modeling and Experimental Study of the Normal Contact Stiffness of Rough Surfaces in Grinding 磨削中粗糙表面法向接触刚度的分析、建模和实验研究

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-11-30 DOI: 10.3390/lubricants11120508

Yuzhu Bai, Xiaohong Jia, Fei Guo, Shuangfu Suo

{"title":"Analysis, Modeling and Experimental Study of the Normal Contact Stiffness of Rough Surfaces in Grinding","authors":"Yuzhu Bai, Xiaohong Jia, Fei Guo, Shuangfu Suo","doi":"10.3390/lubricants11120508","DOIUrl":"https://doi.org/10.3390/lubricants11120508","url":null,"abstract":"Grinding is the most important method in machining, which belongs to the category of precision machining processes. Many mechanical bonding surfaces are grinding surfaces. Therefore, the contact mechanism of grinding a joint surface is of great significance for predicting the loading process and dynamic characteristics of precision mechanical products. In this paper, based on the collected grinding surface roughness data, the profile parameters and topography characteristics of the asperity were analyzed, the rough surface data were fitted, the asperity profile was reconstructed, and the parabola y = nx2 + mx + l of the cylindrical asperity model was established. After analyzing the rough surface data of the grinding process, the asperity distribution height was fitted with a Gaussian distribution function, which proved that asperity follows the Gaussian distribution law. The validity of this model was confirmed by the non-dimensional processing of the assumed model and the fitting of six plasticity indices. When the pressure is the same, the normal stiffness increases with the decrease in the roughness value of the joint surface. The experimental stiffness values are basically consistent with the fitting stiffness values of the newly established model, which verifies the reliability and effectiveness of the new model established for the grinding surface. In this paper, a new model for grinding joint surface is established, and an experimental platform is set up to verify the validity of the model.","PeriodicalId":18135,"journal":{"name":"Lubricants","volume":"18 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139208085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Comprehensive Investigation of BN and VC Reinforcements on the Properties of FSP AA6061 Composites 全面研究 BN 和 VC 增强材料对 FSP AA6061 复合材料性能的影响

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-11-30 DOI: 10.3390/lubricants11120507

Essam B. Moustafa, F. Djouider, A. Alhawsawi, Ezzat A. Elmoujarkach, E. Banoqitah, S. S. Mohamed

{"title":"A Comprehensive Investigation of BN and VC Reinforcements on the Properties of FSP AA6061 Composites","authors":"Essam B. Moustafa, F. Djouider, A. Alhawsawi, Ezzat A. Elmoujarkach, E. Banoqitah, S. S. Mohamed","doi":"10.3390/lubricants11120507","DOIUrl":"https://doi.org/10.3390/lubricants11120507","url":null,"abstract":"This present study investigated the impact of incorporating boron nitride (BN) and vanadium carbide (VC) reinforcements on various properties of friction stir processed (FSP) AA6061 alloy composites, focusing specifically on grain structure, thermal conductivity, electrical conductivity, and compressive strength. The findings indicate that VC more effectively refines the grain structure of the AA6061 alloy during FSP compared to BN. The inclusion of BN particles in the metal matrix composites resulted in a decrease in both thermal and electrical conductivity. In contrast, the addition of VC particles led to an increase in both thermal and electrical conductivity. The AA6061/VC composite material exhibited the highest thermal conductivity among all composites tested. The electrical conductivity of the hybrid-composite AA6061/30%BN+70%VC showed a slight reduction, measuring only 2.8% lower than the base alloy AA6061. The mono-composite AA6061/VC exhibited a marginal decrease in thermal conductivity, with a measured value only 7.5% lower than the conventional alloy AA6061. However, the mono-composite AA6061/BN displayed a more significant decline, exhibiting a loss of 14.7% and 13.9% in electrical and thermal conductivity, respectively. The composite material comprising 30% BN and 70% VC reinforcement demonstrated the highest compressive strength compared to all other tested composites. The observed percentage enhancement in the mechanical properties of mono and hybrid composites, compared to the parent AA6061 alloy, ranged from 17.1% to 31.5%.","PeriodicalId":18135,"journal":{"name":"Lubricants","volume":"17 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139201631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fullerene Oil Tribology in Compression Piston Rings under Thermal Considerations 热考虑因素下压缩活塞环中的富勒烯油摩擦学

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-11-30 DOI: 10.3390/lubricants11120505

Elias Tsakiridis, P. Nikolakopoulos

{"title":"Fullerene Oil Tribology in Compression Piston Rings under Thermal Considerations","authors":"Elias Tsakiridis, P. Nikolakopoulos","doi":"10.3390/lubricants11120505","DOIUrl":"https://doi.org/10.3390/lubricants11120505","url":null,"abstract":"To enhance the efficiency of automotive engines, a comprehensive understanding of friction generation within their components is paramount. Moreover, extensive global research efforts have been dedicated to nanoparticles, leading to the emergence of nanolubricants. In this study, an investigation was conducted focused on the piston ring–cylinder tribological interaction using fullerenes as additives. This is a very important issue since the friction forces can be significantly reduced. In order to solve this problem, a 2D CFD approach was implemented, taking into account a roughness model and temperature variations. The obtained results clearly show a friction reduction using fullerenes as additives compared to both synthetic and monograde oils. Furthermore, using fullerene oils, the performance of the compression piston ring system is improved due to friction reduction and the change of the temperature distribution. This study is beyond SOTA, since there is a limited contribution in the field of such nanolubricants in compression piston ring system. It is evident that the friction force is reduced by 42% compared to synthetic oils, showing a perspective on more tribologically efficient internal combustion engines.","PeriodicalId":18135,"journal":{"name":"Lubricants","volume":"126 32","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139197105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Fractal Prediction Method for Contact Stiffness of Helical Gear Considering Asperity Lateral Contact and Interaction 考虑非圆侧面接触和相互作用的螺旋齿轮接触刚度分形预测方法

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-11-30 DOI: 10.3390/lubricants11120509

Xiangyang Xu, Lei Shi, Linfang Fan

{"title":"A Fractal Prediction Method for Contact Stiffness of Helical Gear Considering Asperity Lateral Contact and Interaction","authors":"Xiangyang Xu, Lei Shi, Linfang Fan","doi":"10.3390/lubricants11120509","DOIUrl":"https://doi.org/10.3390/lubricants11120509","url":null,"abstract":"The normal contact stiffness (NCS) on rough surfaces has a significant impact on the dynamic characteristics of helical gear. Aiming at the problem of inaccurate calculation of the NCS model under the traditional Hertz theory of smooth surfaces, a fractal prediction model of helical gear contact stiffness considering asperity lateral contact and interaction between asperities is proposed in this paper. The variation formula of asperity and the correction coefficient of a tooth contact surface under asperity lateral contact and interaction are derived, and the influence of micro-elements on normal load and NCS is qualitatively analyzed. The results show that the NCS of considering the interaction and lateral contact of asperity is closer to the experimental results; the contact surface correction coefficient increases with the increase of curvature radius and load. The NCS of a tooth surface increases with the increase in fractal dimension D or the decrease in roughness amplitude G. The influence of asperity lateral contact and interaction decreases with the increase in D and the decrease in G. The NCS of the helical gear decreases under the lateral contact and interaction of the asperity, which is critical for exact estimation of the NCS of contact surfaces in gear.","PeriodicalId":18135,"journal":{"name":"Lubricants","volume":"214 ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139203673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Two Contributions to Rolling Contact Fatigue Testing Considering Different Diameters of Rail and Wheel Discs 考虑到轨道和轮盘的不同直径，对滚动接触疲劳测试的两项贡献

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-11-30 DOI: 10.3390/lubricants11120504

Jiří Šmach, R. Halama, Martin Marek, M. Šofer, Libor Kovář, P. Matušek

{"title":"Two Contributions to Rolling Contact Fatigue Testing Considering Different Diameters of Rail and Wheel Discs","authors":"Jiří Šmach, R. Halama, Martin Marek, M. Šofer, Libor Kovář, P. Matušek","doi":"10.3390/lubricants11120504","DOIUrl":"https://doi.org/10.3390/lubricants11120504","url":null,"abstract":"Scaled rolling contact fatigue tests, used to practically simulate the wear of the wheel and rail material under laboratory conditions, are typically classified into two categories. Tests in the first category use twin-disc stands, while the second group of test rigs use two discs of different diameters considering the rail disc as the larger one. The latter setup is closer to the real situation, but problems can occur with high contact pressures and tractions. The focus of this paper is on two main contributions. Firstly, a case study based on finite element analysis is presented, allowing the optimization of the specimen geometry for high contact pressures. Accumulated plastic deformation caused by cycling is responsible for abrupt lateral deformation, which requires the use of an appropriate cyclic plasticity model in the finite element analysis. In the second part of the study, two laser profilers are used to measure the dimensions of the specimen in real time during the rolling contact fatigue test. The proposed technique allows the changes in the specimen dimensions to be characterized during the test itself, and therefore does not require the test to be interrupted. By using real-time values of the specimen’s dimensional contours, it is possible to calculate an instantaneous value of the slip ratio or the contact path width.","PeriodicalId":18135,"journal":{"name":"Lubricants","volume":"1206 ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139203865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on the Lubricating Characteristics of Graphene Lubricants 石墨烯润滑剂的润滑特性研究

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-11-30 DOI: 10.3390/lubricants11120506

Yi Dong, Biao Ma, Cenbo Xiong, Yong Liu, Qin Zhao

引用次数: 0

Bearing Digital Twin Based on Response Model and Reinforcement Learning 基于响应模型和强化学习的轴承数字双胞胎

IF 3.5 3区工程技术

Lubricants Pub Date : 2023-11-27 DOI: 10.3390/lubricants11120502

Zhaorong Li, Jiaoying Wang, Diwang Ruan, Jianping Yan, C. Gühmann

{"title":"Bearing Digital Twin Based on Response Model and Reinforcement Learning","authors":"Zhaorong Li, Jiaoying Wang, Diwang Ruan, Jianping Yan, C. Gühmann","doi":"10.3390/lubricants11120502","DOIUrl":"https://doi.org/10.3390/lubricants11120502","url":null,"abstract":"In recent years, research on bearing fault modeling has witnessed significant advancements. However, the modeling of bearing faults using digital twins (DTs) remains an emerging area of exploration. This paper introduces a bearing digital twin developed by integrating a signal-based response model with reinforcement learning techniques. Initially, a signal-based model is constructed, comprising a unit fault impulse function and a decay oscillation function. This model illustrates the bearing’s acceleration response under fault conditions and acts as the environmental component within the bearing digital twin. Subsequently, a parameter estimation process identifies two critical parameters from the signal-based model: the load proportional factor and the decaying constant. The Deep Deterministic Policy Gradient (DDPG) algorithm is employed as the agent for online learning of these parameters. The cosine similarity metric is employed to define the state and reward by comparing the real acceleration measurements with the simulation data generated by the digital twin. To validate the effectiveness of the digital twin, experimental data sourced from the three datasets are utilized. The results underscore the digital twin’s capacity to faithfully replicate the bearing’s acceleration response under diverse conditions, demonstrating a high degree of similarity in both the time and frequency domains.","PeriodicalId":18135,"journal":{"name":"Lubricants","volume":"1 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139229827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0