Journal of Tribology最新文献_第3页

Improving signal transmission quality of wind turbine pitch slip ring with copper matrix composites 用铜基复合材料提高风力发电机变桨滑环的信号传输质量

Journal of Tribology Pub Date : 2024-06-04 DOI: 10.1115/1.4065658

Da Wen, Minglang Zhang, Rui Zhu, Xue Zuo, Yuankai Zhou

引用次数: 0

Point Contact EHL and Wear in Intermittent Motion 点接触 EHL 和间歇运动中的磨损

Journal of Tribology Pub Date : 2024-06-04 DOI: 10.1115/1.4065662

Mingyu Zhang, Xinqing Wang, Yiming Han, Jing Wang, C. Venner

{"title":"Point Contact EHL and Wear in Intermittent Motion","authors":"Mingyu Zhang, Xinqing Wang, Yiming Han, Jing Wang, C. Venner","doi":"10.1115/1.4065662","DOIUrl":"https://doi.org/10.1115/1.4065662","url":null,"abstract":"\u0000 Intermittent motion is a complex process that involves constant speed, deceleration, static stages and acceleration. Theoretical analysis suggests that shortening the period of intermittent motion can increase the film thickness during static stages, thereby extending the life of the part. Currently, an increasing number of studies are focusing on small oscillatory movements or vibrations. However, the impact of intermittent motion cycles on the film thickness and wear in the contact area still needs to be investigated. Optical interference and acoustic emission (AE) were employed as experimental methods to investigate simple sliding point contact intermittent motion. The lubrication state transition of full film-starvation-wear in the contact area was observed and the experimental results confirmed the correctness of the elastohydrodynamic lubrication (EHL) theoretical analysis. Additionally, the regularity of starvation and AE signal change with time during intermittent motion were summarized. An in-depth analysis of the reasons why intermittent motion with a short period generates less wear was performed. This analysis provides novel ideas to reduce wear of intermittent motion mechanisms. Overall, this research contributes to the understanding of the wear during intermittent motion and provides essential insights for wear reduction in this area.","PeriodicalId":509807,"journal":{"name":"Journal of Tribology","volume":"5 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141267547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Friction and wear of Ni alloy-Ag-Ni doped hBN self-lubricating composites from room temperature to 800 °C 掺杂 hBN 的镍合金-镁-镍自润滑复合材料从室温到 800 °C 的摩擦和磨损情况

Journal of Tribology Pub Date : 2024-06-04 DOI: 10.1115/1.4065660

Smita Gupta, R. Tyagi, Anchal Pandey, Pramod Jain, Om P. Khatri

{"title":"Friction and wear of Ni alloy-Ag-Ni doped hBN self-lubricating composites from room temperature to 800 °C","authors":"Smita Gupta, R. Tyagi, Anchal Pandey, Pramod Jain, Om P. Khatri","doi":"10.1115/1.4065660","DOIUrl":"https://doi.org/10.1115/1.4065660","url":null,"abstract":"\u0000 The current investigation explores the potential of Ni doped hBN (hBN-O-Ni) as a solid lubricant in conjunction with Ag in affecting the tribological performance of Ni alloy-Ag- hBN composites containing a fixed amount of silver (10 wt.%) and different amounts (2, 4, 6 and 8 wt.%) of hBN from room temperature to 800 °C by carrying out tests under a fixed load of 5N and speed of 0.5 m/s using a ball-on-disk tribometer. The study also intends to determine the optimum content of addition of hBN requited to attain low friction and low wear properties over the entire range of temperature. The composite having 8 wt. % hBN has shown the lowest coefficient of friction (~ 0.18) at 800 °C due to synergetic action between silver molybdates and hBN. However, the composite containing 4 wt. % hBN has the optimum tribological properties under the conditions used in the present study. At low temperatures, Ag and hBN provided lubrication, whereas at high temperatures lubricious oxides (NiO, NiMoO4 and MoO3), silver molybdates (Ag2MoO4, Ag2Mo2O7) and hBN contributed to lowering the coefficient of friction as well as wear rate.","PeriodicalId":509807,"journal":{"name":"Journal of Tribology","volume":"12 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141266305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

EFFECT OF ENTRAINMENT SLIDING DIRECTION TO THE TRACTION COEFFICIENT FOR EHL ELLIPTICAL CONTACTS IN THE LINEAR ISOTHERMAL REGION 夹带滑动方向对线性等温区 EHL 椭圆形接触牵引系数的影响

Journal of Tribology Pub Date : 2024-06-04 DOI: 10.1115/1.4065661

Yuko Higashitani, S. Kawabata, M. Björling, A. Almqvist

{"title":"EFFECT OF ENTRAINMENT SLIDING DIRECTION TO THE TRACTION COEFFICIENT FOR EHL ELLIPTICAL CONTACTS IN THE LINEAR ISOTHERMAL REGION","authors":"Yuko Higashitani, S. Kawabata, M. Björling, A. Almqvist","doi":"10.1115/1.4065661","DOIUrl":"https://doi.org/10.1115/1.4065661","url":null,"abstract":"\u0000 In many mechanical systems, elastohydrodynamic lubrication (EHL) is apparent in the interfaces be-tween rolling/sliding parts. Even at small slide-to-roll ratios, detailed knowledge about the oil film thickness and the traction exerted by the highly pressurized lubricant is crucial for the efficiency and reliability of such systems. In this study, we explore the impact of surface velocity direction and contact ellipticity on traction characteristics within EHL through numerical simulations using an elliptical EHL contact solver based on a fully-coupled finite-element approach. We present a novel master curve that correlates the traction coefficient slope with the lubricant entrainment direction and ellipticity, for el-liptical EHL contacts in the piezo-viscous elastic (PE) regime. We demonstrate that the master curve, shows a maximum relative difference of less than 3.2% to the numerical simulation results, proving its efficacy. This curve is particularly beneficial for multibody dynamics models, providing a reliable tool for predicting frictional forces in systems where elliptical EHL contacts, operating within the PE regime at low SRR, are prevalent.","PeriodicalId":509807,"journal":{"name":"Journal of Tribology","volume":"12 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141267518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of TiO2-SiC and heat treatment on tribological characteristics of bimodal hybrid aluminium composites under dry sliding condition TiO2-SiC 和热处理对干滑动条件下双峰混合铝复合材料摩擦学特性的影响

Journal of Tribology Pub Date : 2024-05-24 DOI: 10.1115/1.4065602

Subodh Kumar, G. Dixit, Savita Dixit

引用次数: 0

Effect of Cavity Shapes on the Lubrication Performance of High Precision Static and Dynamic Thrust Bearing under Eccentric Load 空腔形状对偏心载荷下高精度静态和动态推力轴承润滑性能的影响

Journal of Tribology Pub Date : 2024-05-20 DOI: 10.1115/1.4065555

Xiaodong Yu, Yanlong Lin, Peng Wang, Zhiyuan Lan, Mingjuan Shao, Lu Li, Enzhao Li, Xinyi Yang, Ruichun Dai, Wentao Jia, Junfeng Wang, Jianhua Jiao, Hui Jiang

{"title":"Effect of Cavity Shapes on the Lubrication Performance of High Precision Static and Dynamic Thrust Bearing under Eccentric Load","authors":"Xiaodong Yu, Yanlong Lin, Peng Wang, Zhiyuan Lan, Mingjuan Shao, Lu Li, Enzhao Li, Xinyi Yang, Ruichun Dai, Wentao Jia, Junfeng Wang, Jianhua Jiao, Hui Jiang","doi":"10.1115/1.4065555","DOIUrl":"https://doi.org/10.1115/1.4065555","url":null,"abstract":"\u0000 The oil cavity shapes, which represent the spatial structures for storing lubricant in static and dynamic thrust bearings, and offset distances, defined as the horizontal distances between the load center and the bearing rotational axis under eccentric loads, directly impact the flow mode of lubricant, pressure, and temperature distribution during bearing operation, so these are the key factors that influence the lubrication performance and the accuracy of bearings. The equations for flow and load capacity of the sector, runway, and double rectangular cavities are derived, and mathematical models are established for different cavities at various tilt positions. Then pressure and temperature fields at different offset distances are analyzed. As the offset distances increase, there is a corresponding increase in the maximum pressures within the sector, runway, and double rectangular cavities by 90.5 kPa, 93.3 kPa, and 30.9 kPa, but average pressures show only minor fluctuations. Concurrently, the maximum temperatures within these cavity shapes are observed to increase by 0.5 K, 0.6 K, and 0.8 K, respectively. The results show that appropriate offset distance can improve the lubrication performance. The runway cavity has the highest load-carrying capacity among the three cavity shapes, while the sector cavity experiences the slightest temperature increase. As the temperature increase in all three cavity shapes is small, the runway cavity exhibits superior performance. The error between simulation and experimental results is less than 10%, which verifies the correctness of the simulation method.","PeriodicalId":509807,"journal":{"name":"Journal of Tribology","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141120351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Implementation of a New Smart-Lubricant Model Using Generalized Newtonian Approach in Soft Elastohydrodynamic Lubrication 在软弹性流体动力润滑中使用广义牛顿法实现新型智能润滑剂模型

Journal of Tribology Pub Date : 2024-05-09 DOI: 10.1115/1.4065496

Nirav Meghpara, Punit Kumar, Gian Bhushan

{"title":"Implementation of a New Smart-Lubricant Model Using Generalized Newtonian Approach in Soft Elastohydrodynamic Lubrication","authors":"Nirav Meghpara, Punit Kumar, Gian Bhushan","doi":"10.1115/1.4065496","DOIUrl":"https://doi.org/10.1115/1.4065496","url":null,"abstract":"\u0000 This is an inceptive attempt to replace the classical Bingham fluid model with a continuous double Newtonian power-law-based constitutive equation for smart lubricants like magneto-rheological, electro-rheological, and ferro-fluids. The implementation of Bingham model in hydrodynamic (HD) and elastohydrodynamic (EHD) lubrication analyses is highly challenging and inconvenient due to its inherent discontinuity. Therefore, the present work demonstrates the use of an already existing rheological model with an appropriate set of parameters to describe the flow behavior of smart lubricants in a soft-EHD lubrication algorithm based on the generalized Newtonian approach. The formation of both floating and adherent cores validates the proposed model. An extensive parametric study is also performed to explore the effects of operating speed, load, and slide-to-roll ratio on the soft-EHL characteristics. The results are very promising, showing that it's possible to customize smart lubricants to match specific operating conditions. This is achieved by adjusting the yield stress value accordingly, allowing for the desired variation in lubrication characteristics.","PeriodicalId":509807,"journal":{"name":"Journal of Tribology","volume":" 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140995479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of Post-processing and Build Direction on the Wear Behaviour of Laser Powder Bed Fused Maraging Steel 后处理和构建方向对激光粉末床熔融马氏体时效钢磨损行为的影响

Journal of Tribology Pub Date : 2024-05-09 DOI: 10.1115/1.4065499

Basil Kuriachen, Katari Vinay, Jino Joshy

{"title":"Influence of Post-processing and Build Direction on the Wear Behaviour of Laser Powder Bed Fused Maraging Steel","authors":"Basil Kuriachen, Katari Vinay, Jino Joshy","doi":"10.1115/1.4065499","DOIUrl":"https://doi.org/10.1115/1.4065499","url":null,"abstract":"\u0000 Present study investigates the effect of post processing (heat treatment: solutionising at 850°C for 2 hr with aging at 490°C for 3 hr and cryogenic treatment at -196°C for 24 hr) and the effect of build direction (along the build direction (BD) and perpendicular to the build direction (PBD)) on the wear behavior of maraging steel fabricated by Laser powder bed fusion (LPBF). The results are also compared with conventional hot-forged samples. The pin on disc equipment was used to conduct the wear experiments with an EN31 steel disk as the counter body. Heat treatment decreased the wear rate of LPBF material by 54.78% and 83.84% in BD and PBD, respectively. This is due to the restriction of grain expansion by the Ni-based precipitants in age hardening treatment. The cryogenic treatment further decreased the wear rate of LPBF material by 87.84% and 90.9% in BD and PBD, respectively. This significant reduction can be attributed to the change of phase to martensite, as confirmed through microstructure and X-ray diffraction (XRD) analysis. Moreover, hot forged material also obtained a reduced wear rate after heat and cryogenic treatments. The highest wear resistance was found with the LPBF cryo-treated BD sample due to increased hardness from 388 HV to 640 HV. The worn surface of test samples was examined by using scanning electron microscopy (SEM), energy dispersive X-ray (EDX), 3D profilometer, and XRD analysis. Oxidation wear, adhesive wear, and abrasive wear are the predominant wear mechanisms identified using SEM.","PeriodicalId":509807,"journal":{"name":"Journal of Tribology","volume":" 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140996741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hydrodynamic Thrust Bearing Test Rig with Novel Bearing Alignment System 配备新型轴承对中系统的推力轴承水动力试验台

Journal of Tribology Pub Date : 2024-05-09 DOI: 10.1115/1.4065500

C. Fais, Muhammad Ali, Isaiah Yasko

{"title":"Hydrodynamic Thrust Bearing Test Rig with Novel Bearing Alignment System","authors":"C. Fais, Muhammad Ali, Isaiah Yasko","doi":"10.1115/1.4065500","DOIUrl":"https://doi.org/10.1115/1.4065500","url":null,"abstract":"\u0000 This study presents the design and development of a new hydrodynamic thrust bearing test rig with a novel (patent pending) hydrodynamic pressure feedback bearing alignment control system. The bearing alignment system maintains even distribution of thrust load across the bearing thrust pads using active hydrodynamic pressure as input to manipulate bearing orientation with stepper motors. The test rig is used to conduct performance evaluation of fixed geometry hydrodynamic thrust bearings with variable taper depths. The influence of helical taper angle, rotational speed, and applied load on key performance characteristics including minimum oil film thickness (MOFT), hydrodynamic pressure distribution, and bearing temperature is presented and analyzed. A numerical model based on the Reynolds equation is used to support the experimental results obtained. Trends in performance established by the numerical analysis show mutually agreeable results compared to experimental data. The average percent deviation of the experimentally gathered change in MOFT as load is increased with respect to the numerically predicted values is 24%. Comparison of experimental to numerical pressure distribution data shows an overall average percent deviation of 32%.","PeriodicalId":509807,"journal":{"name":"Journal of Tribology","volume":" 19","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141128888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of direct aging heat treatment on microstructure and mechanical properties of Laser Powder Bed Fused Maraging steel 300 grade alloy 直接时效热处理对激光粉末床熔融马氏体时效钢 300 级合金微观结构和机械性能的影响

Journal of Tribology Pub Date : 2024-05-09 DOI: 10.1115/1.4065498

Subba Rao Bheemavarapu, Thella Babu Rao, Mondi Rama Karthik

{"title":"Effect of direct aging heat treatment on microstructure and mechanical properties of Laser Powder Bed Fused Maraging steel 300 grade alloy","authors":"Subba Rao Bheemavarapu, Thella Babu Rao, Mondi Rama Karthik","doi":"10.1115/1.4065498","DOIUrl":"https://doi.org/10.1115/1.4065498","url":null,"abstract":"\u0000 This paper investigates the effects of a 6-hour direct aging heat treatment at 490°C on the mechanical, tribological, and microstructure characteristics of laser powder bed fused maraging 300 steels, which is produced at various laser energy densities. After direct aging heat treatment, the grain boundaries become irregular and vague due to the residual stress releasing, squeezing of precipitates into the grain boundaries, and phase transformations. The XRD analysis reveals the reverted austenite (γ') phase forms during age treatment due to the inevitable reversion of metastable martensite to the stable reverted γ' phase. The heat-treated samples microhardness rises with rising the Laser Energy Density (LED) from 61.33 to 92.10 J/mm3 due to a decrease in the reversed austenite phase and a further rise in LED decreases the microhardness due to a rise in the reversed austenite phase. The heat-treated sample produced at LED of 92.10 J/mm3 shows maximum yield, ultimate tensile strengths, and minimum elongation percentage due to its high microhardness, and the fractography results show the failure mode as a mixed brittle and ductile fracture. The wear rate of the heat-treated additively manufactured maraging 300 steel decreases as the LED increases from 61.41 to 92.1 J/mm3 and a further rise in LED increases the wear rate. The wear rate rises with a rise in sliding velocity from 1.5-3.5 m/s. The dominant wear mechanism was observed as abrasion with small grooves and saplings.","PeriodicalId":509807,"journal":{"name":"Journal of Tribology","volume":" 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140996915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0