Lubrication Science最新文献

{"title":"Lubrication Mechanism of TC4 Titanium Alloy Against Silicon Nitride by ILs ([Li (Synthetic Esters)] NTF2)","authors":"Feizhou Li,&nbsp;Bian Guo,&nbsp;Gexia Yuan,&nbsp;Zhaozhao Yang,&nbsp;Murong Gao,&nbsp;Yu Wang,&nbsp;Dongping Tian","doi":"10.1002/ls.1704","DOIUrl":"10.1002/ls.1704","url":null,"abstract":"<div>\u0000 \u0000 <p>The ILs ([Li (synthetic esters)] NTF₂) were prepared by the in situ synthesis method. The tribological behaviour of the ILs to friction pairs of Ti-6Al-4V titanium alloy against silicon nitride was studied by SRV-V under different concentrations and friction frequencies; the wear scar was studied by SEM, XPS and TOF-SIMS. The results showed that the friction coefficient and wear loss decreased gradually with the increase of the LiNTF₂ content; when the LiNTF₂ content reached a certain value (10%), the friction coefficient and wear loss did not change much. Tribofilm composed of titanium oxide, Al₂O₃, TiFO₂, AlOF₂, Ti₂O₄F and Al₂O₃F plays a major role in lubrication and anti-friction effect.</p>\u0000 </div>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 7","pages":"489-499"},"PeriodicalIF":1.8,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140592827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Susceptibility of Poly–Alpha Olefin and Diisooctyl Sebacate Base Oils With Different Polarities to Oleic Acid Surface–Capped Ultra-Small Cerium Oxide Nanoparticle","authors":"Lijie Bian,&nbsp;Ningning Song,&nbsp;Laigui Yu,&nbsp;Yujuan Zhang,&nbsp;Pingyu Zhang,&nbsp;Shengmao Zhang","doi":"10.1002/ls.1703","DOIUrl":"10.1002/ls.1703","url":null,"abstract":"<div>\u0000 \u0000 <p>A key issue for nano-additive to effectively exert tribological function is to ensure its entrance to and adhesion on the frictional contact surfaces. But the adhesion of nano-additive on the rubbed surfaces under oil lubrication faces the challenge of the competitive adsorption of lubricant base oil thereon. In this study, oleic acid–modified ultra-small cerium oxide (OA-CeO₂) nanoparticle was synthesised by one-pot liquid-phase surface-modification method in the presence of OA as the surface modifier. The susceptibility of non-polar poly–alpha olefin 6 (PAO6) and polar diisooctyl sebacate (DIOS) base oils to the as-prepared OA-CeO₂ nano-additive was investigated, and the effect of the OA-CeO₂ nano-additive on the friction-reducing and anti-wear abilities of the two kinds of base oils towards a steel–steel sliding contact was investigated with four-ball friction and wear tester. Furthermore, the tribological mechanism of the adsorption and deposition of the OA-CeO₂ nano-additive on the surface of friction steel and the competitive adsorption of base oil were discussed. Characterisations by scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy demonstrate that the as-prepared OA-CeO₂ nanoparticle is of a spherical shape and has an ultra-small average size of 1.2 nm. As the lubricant additive in PAO6 and DIOS base oils, the OA-CeO₂ nano-additive exhibits different tribological properties, which is attributed to the difference in the base oils' polarity. Namely, the CeO₂ nanoparticle in the non-polar PAO6 base oil is more easily adsorbed on the rubbed surface of the steel–steel sliding contact, thereby forming the CeO₂ deposition film to improve the tribological properties of the base oil. However, the CeO₂ nanoparticle added in polar DIOS base oil is difficult to form the CeO₂ deposition film, because of the competitive and preferential adsorption of the polar base oil on the rubbed steel surface. Therefore, it is imperative to select the base oils with proper polarity to better exert the friction-reducing and anti-wear functions of the OA-CeO₂ nano-additive.</p>\u0000 </div>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 6","pages":"478-488"},"PeriodicalIF":1.8,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140592823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Friction-Reducing and Anti-Wear Mechanism of BP/Nano-Fe3O4 Nanocomposite as a Lubricant Additive in Soybean Oil","authors":"Han Yu,&nbsp;Min Li,&nbsp;Jianfang Sun,&nbsp;Jingying Su,&nbsp;Fenghua Su","doi":"10.1002/ls.1707","DOIUrl":"10.1002/ls.1707","url":null,"abstract":"<div><p>As an emerging two-dimensional material, black phosphorus (BP) has excellent tribological properties, but the poor dispersion of BP in oil inhibits its application in friction to some extent. Surface modification is one of the effective methods to solve the dispersibility of BP, and the use of nano-Fe₃O₄ dotted on the surface of BP improves the dispersion stability of BP in soybean from 3 days to about 15 days. Compared with pure soybean oil, friction coefficient and wear rate of the addition of 0.12 wt% BP/Fe₃O₄ are reduced 65% and 78%, respectively. To elucidate the excellent tribological mechanisms of BP/Fe₃O₄ as additives in soybean oil, the compositional and structural characterisation of the abrasion mark surface was studied accordingly. On the one hand, soybean oil reacts with BP/Fe₃O₄ to form a composite tribo-film during the scraping process. This tribo-film composed of amorphous carbon, iron oxide and phosphorus oxide nitrides prevents direct contact between the sliding interfaces. On the other hand, BP and Fe₃O₄ nanoparticles form a mechanical rollerball structure, which can further reduce interfacial friction and wear through synergistic lubrication. The results provide new insights into the design of additives in biomass lubricating oils and propose new application prospects for BP in the field of lubricating additives.</p></div>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 6","pages":"468-477"},"PeriodicalIF":1.8,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140592669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Ageing of Rolling Oil on the Performance of Cold-Rolled Steel","authors":"Subho Chakraborty,&nbsp;Suvendu Sekhar Giri,&nbsp;A. Pandit,&nbsp;A. N. Bhagat,&nbsp;Ravi Prakash,&nbsp;Ajay Kumar Jha","doi":"10.1002/ls.1708","DOIUrl":"10.1002/ls.1708","url":null,"abstract":"<div><p>Interaction between the cold rolling oil and substrate at the roll bite has always intrigued the tribologists. In plant conditions, it has been observed that occurrences of surface defects on cold-rolled FHCR coils increase with the ageing of cold rolling emulsion. In this study, the rolling oil was aged at different lab conditions to replicate 6 and 11 months of rolling oil ageing from a particular cold rolling mill. The studies indicated an increase in acid number of the oil. Tribological studies indicated an increase in CoF along with an increase in wear phenomenon on the substrate. The removability of the surface oil becomes difficult with ageing which could lead to potential surface oil residues remaining on the strip after degreasing, resulting in surface defects and dirty coils after annealing. Deterioration in anti-stain property is also observed as ageing progresses. The deterioration in performance is mainly governed by the depletion in additives and generation of free fatty acids within the rolling oil bath. Proper maintenance of the bath ensures lesser defect formation.</p></div>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 6","pages":"457-467"},"PeriodicalIF":1.8,"publicationDate":"2024-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140592664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of oleic acid modified GO-LaF3 on lubrication characteristics of 10# white oil","authors":"Tianxia Liu,&nbsp;Jian Qin,&nbsp;Jian Wang,&nbsp;Jing Li,&nbsp;Jinyu Liu","doi":"10.1002/ls.1700","DOIUrl":"10.1002/ls.1700","url":null,"abstract":"<p>To study the synergistic lubricating effects of graphene oxide (GO) and lanthanum fluoride (LaF₃), and find a new anti-wear additive, oleic acid surface-modified graphene oxide-lanthanum fluoride (OA-GO-LaF₃, OGL) composite nano-additive was prepared by hydrothermal method by using oleic acid as the modifier. The morphology, structure, composition, element valence, thermal stability and tribological properties of nano additives were characterised by a series of modern characterisation methods. Results show that OGL has a higher degree of graphitization, smaller particle size, more homogeneous disperse, higher LaF₃ load and stronger thermal stability than that of GL. The tribological properties of OGL which is modified by oleic acid are better than unmodified GL. Analysis of the friction mechanism shows that both OGL and GL can generate LaF₃ physical adsorption films through adsorption during the friction process and tribochemical reactions film containing lanthanum compounds, carbon oxide compounds, and iron oxide compounds on the friction surface. These physical adsorption films and chemical reaction film can improve lubrication.</p>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 6","pages":"444-456"},"PeriodicalIF":1.8,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140592821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PVD coated dies in action: Exploring finite element analyses for sheet metal forming of high-strength steel","authors":"S. Sivarajan,&nbsp;Diogo M. Neto,&nbsp;Marta C. Oliveira,&nbsp;Padmanabhan Raghupathy,&nbsp;Luis F. Menezes","doi":"10.1002/ls.1696","DOIUrl":"10.1002/ls.1696","url":null,"abstract":"<p>This research proposes a complete analysis of the use of physical vapour deposition coated dies in the sheet metal forming process for high-strength-steel sheets. The goal of the proposed approach is to investigate how PVD coatings affect die performance and how that affects the formability and quality of the high-strength-steel-sheets that are made. The finite element analyses are used to simulate and evaluate the mechanical behaviour and deformation characteristics during the forming process. Studies to enhance the forming characteristics of these materials, typically denoted by limiting draw ratio and maximum punch force are required. A reduction in punch force required and improved limiting draw ratio is observed that is attributed to the enhanced contact with friction-conditions in the die-sheet interfaces. The experimental results are compared with simulation results from DD3IMP, a code used for deep drawing simulations, and it is evident that the experimental outcomes are analysed well with the simulation results.</p>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 6","pages":"431-443"},"PeriodicalIF":1.8,"publicationDate":"2024-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140001587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the lubrication performance of circular tilting pad thrust bearings for large wind turbines","authors":"Jianlei Wang,&nbsp;Yang Cao,&nbsp;Wenye Sun,&nbsp;Runlin Chen,&nbsp;Qian Jia,&nbsp;Yahui Cui","doi":"10.1002/ls.1681","DOIUrl":"10.1002/ls.1681","url":null,"abstract":"<p>In view of the large temperature rise and impact load of thrust bearings in the main shaft system of large wind turbines, this article takes the circular tilting pad thrust bearings in large wind turbines as the research object, and analyses the basic theory of bearing lubrication. The lubrication performance calculation model established for this bearing includes the Reynolds equation, energy equation, film thickness equation, and elastic deformation equation. Theoretically analysing and calculating the lubrication performance of the circular tilting pad thrust bearing, the key performance parameters have identified such as minimum film thickness (<i>h</i>_min), temperature rise (Δ<i>T</i>), power consumption (<i>W</i>), and flow rate (<i>Q</i>). The calculation results show that the eccentricity ratio has a significant impact on the lubrication performance of the circular tilting pad thrust bearing. When both radial and circumferential eccentricity ratios are around 0.5, the bearing exhibits a high temperature rise, leading to a potential risk of bearing burnout. The results also show that at a radial eccentricity ratio of approximately 0.54, the minimum film thickness reaches its maximum value of 10.34 μm. Similarly, at a circumferential eccentricity ratio of about 0.60, the minimum film thickness reaches its peak value of 21.89 μm. This indicates that the eccentricity ratio plays a crucial role in the lubrication performance. In addition, the lubrication performance of the bearing under varying loads has been calculated at a speed of 9.5 r/min. The results demonstrated that the applied load significantly impacts the thrust bearing's performance. The findings elucidate the critical role of considering the eccentricity ratio and operational external load during the bearing design process. This study validates the potential of replacing rolling bearings with sliding bearings in wind turbine main shafts. It also provides a theoretical reference for the future design of sliding bearings.</p>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 6","pages":"421-430"},"PeriodicalIF":1.8,"publicationDate":"2024-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139954781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coupling effect of partial composite texture and thermal effect on the performance of hydrostatic bearing","authors":"Dongju Chen,&nbsp;Yu Cui,&nbsp;Kun Sun,&nbsp;Jinwei Fan,&nbsp;Kai Cheng","doi":"10.1002/ls.1702","DOIUrl":"10.1002/ls.1702","url":null,"abstract":"<p>This work is focused on performance computation of high speed rotor bearing system with partial composite texture. Since its viscosity at varying speeds affects working performance in different partial composite texture, therefore at design and development stage, it is necessary to know the composite texture and thermal effect acting on rotor-bearing system that causes variation of performance. The effects of partial composite texture size and position on the performance of the bearing are studied. After the optimal structural parameters are determined, the effects of the partial composite texture and fluid thermos structure coupling on the bearing capacity, stiffness, and friction coefficient of the oil film are analysed. The results show that after considering the influence of thermal effect, the performance enhancement of composite texture bearing is better than that of smooth bearing. Considering the temperature effect, the bearing capacity of the composite textured bearing is increased by 51.4% compared with that of the smooth bearing, and the friction coefficient is reduced to 22.4%, which is better than the value without considering the temperature effect, the accuracy of the results is verified by experiments. This study provides a theoretical basis for the design of hydrostatic bearing and improving its performance.</p>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 5","pages":"407-419"},"PeriodicalIF":1.8,"publicationDate":"2024-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139954777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parameter design and dynamic stability of controllable damping ferrofluid bearing","authors":"Xuhui Liu,&nbsp;Wenqiang Xu,&nbsp;Huina Hu,&nbsp;Yan Wu,&nbsp;Pianpian Yan,&nbsp;Bin Xu","doi":"10.1002/ls.1701","DOIUrl":"10.1002/ls.1701","url":null,"abstract":"<p>The purpose of this paper is to carry out parameter design and dynamic stability verification experiment of controllable damping ferrofluid bearing. A new type of ferrofluid bearings is designed, and its internal magnetic fields are simulated by the finite element analysis software ANSYS. In this paper, the coefficient of magnetic leakage is taken as the optimization object, and the optimal parameters of ferrofluid bearings are updated. At the same time, the working principle of the ferrofluid bearings test platform is introduced, which includes a servomotor with a controller, an eddy displace sensor, an amplifier and a power supply. Finally, the dynamic stability of ferrofluid bearing is verified by experiments. The experimental results show that when the applied current is less than or equal to 0.08 A, the amplitude of the rotor supported by the ferrofluid bearing decreases with the applied current increment. Besides, the dynamic stability of the rotor is also related to the rotational speed. When the applied current is 0.08 A, the amplitude of the rotor supported by the ferrofluid bearing firstly increases and then decreases with the rotational speed increment. It is proved that the ferrofluid bearings have a strong function of the dynamic stability, which can suppress the vibration of the rotor, and have high accuracy of both position and rotation.</p>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 5","pages":"396-406"},"PeriodicalIF":1.8,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139954884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the effect of micro-texture coating tool on the milling quality of wood surface","authors":"Dejin Wang,&nbsp;Hang Yin,&nbsp;Li Feng","doi":"10.1002/ls.1699","DOIUrl":"10.1002/ls.1699","url":null,"abstract":"<p>With the gradual increase of the demand for wooden products, people's requirements for processing quality of wooden products become higher. In this work, the dimension of groove micro-texture is determined by finite element simulation analysis of tool structure strength. In this article, by designing milling experiments, the wood surface quality and wood surface morphology after milling with ordinary tools, micro-textured tools, coated tools and micro-textured coated tools are compared. The experimental results show that the quality of wood surface after milling with micro-texture coating tool is better than that of the other three kinds of tools. And the wood surface after milling with micro-texture coating tool is smooth, and the processing defects, such as burr and crack are less. In other words, micro-texture technology combined with surface coating technology can effectively improve the surface quality of wood after milling.</p>","PeriodicalId":18114,"journal":{"name":"Lubrication Science","volume":"36 5","pages":"387-395"},"PeriodicalIF":1.8,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139792100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}