Tribology International最新文献_第6页

Improved high-temperature tribological properties in Cr2AlC MAX films via friction-induced glaze layer formation 通过摩擦诱导釉层形成改善Cr2AlC MAX薄膜的高温摩擦学性能

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-23 DOI: 10.1016/j.triboint.2026.111742

Bingsen Jia , Xiaowei Tang , Wenju Xu , Xinyu Jiang , Xiaohong Liu , Li Ji , Kunjie Wang , Hongxuan Li

Owing to their unique layered hexagonal crystal structure and hybrid metallic-covalent bonding characteristics, Cr₂AlC MAX-phase ceramics exhibit outstanding thermal conductivity, oxidation resistance, and thermal stability at elevated temperatures. These properties render them highly sought after for tribological systems operating in extreme environments. This work investigates the dry sliding tribological behaviour of Cr₂AlC films in air between 700 and 900 ℃, examining the temperature-dependent evolution of their friction and wear characteristics, as well as the corresponding oxidation protection mechanisms. Results indicate that the coefficient of friction decreases progressively with increasing temperature, while the wear rate exhibits a non-monotonic trend, initially increasing followed by a reduction. At 900 ℃, the wear rate diminishes significantly to 1.2 × 10⁻⁵ mm³/(N·m), demonstrating exceptional high-temperature lubrication performance. This superior performance is primarily attributed to the in situ formation of a continuous, dense Cr₂O₃-Al₂O₃ composite oxide film on the friction contact surface. This oxide film not only enhances the material's shear resistance but also effectively isolates direct contact between the mating surfaces, thereby transforming the wear mechanism from abrasive wear-dominated to oxide film lubrication-dominated. Furthermore, in high-temperature oxidation experiments, the selective outward diffusion of Al serves as the key driver for the formation of the protective Al₂O₃ layer. As temperatures rise further, Cr tends to precipitate at Al₂O₃ grain boundaries or defect sites, effectively filling microscopic diffusion channels within the oxide layer and enhancing structural integrity. This research provides new insights for the design and application of MAX phase ceramics in high-temperature friction systems.

由于其独特的层状六方晶体结构和杂化金属共价键特性，Cr2AlC max相陶瓷在高温下表现出优异的导热性、抗氧化性和热稳定性。这些特性使其在极端环境下的摩擦学系统中备受追捧。本研究研究了Cr2AlC薄膜在700 - 900℃空气中的干滑动摩擦学行为，研究了其摩擦磨损特性的温度依赖演变，以及相应的氧化保护机制。结果表明：摩擦系数随温度升高而逐渐减小，磨损率呈现先增大后减小的非单调趋势；在900℃时，磨损率显著降低至1.2 × 10−5 mm3/(N·m)，表现出优异的高温润滑性能。这种优异的性能主要归功于在摩擦接触面上原位形成连续致密的Cr2O3-Al2O3复合氧化膜。这种氧化膜不仅提高了材料的抗剪切能力，而且有效地隔离了配合面之间的直接接触，从而使磨损机制从磨料磨损为主转变为氧化膜润滑为主。此外，在高温氧化实验中，Al的选择性向外扩散是Al2O3保护层形成的关键驱动因素。随着温度的升高，Cr倾向于在Al₂O₃晶界或缺陷部位析出，有效地填充了氧化层内部的微观扩散通道，增强了结构的完整性。该研究为MAX相陶瓷在高温摩擦系统中的设计和应用提供了新的思路。

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引用次数: 0

Influence of morphology on friction anisotropy of GLAD Mo films 形貌对GLAD Mo薄膜摩擦各向异性的影响

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-23 DOI: 10.1016/j.triboint.2026.111721

Guilherme B. Rodrigues , Pascal Boulet , Nicolas Martin , Fabien Amiot , Guillaume Colas

Frictional behavior of molybdenum thin films deposited by Glancing Angle Deposition (GLAD) was investigated at various deposition angles (

α

) using single-scratch tests under different loads and directions. Films deposited at

α \geq 5 0^{\circ}

developed elliptical columnar structures, resulting in orthotropic anisotropy due to direction-dependent plastic deformation. Increasing the deposition angle enhanced intercolumnar porosity, thereby reducing both friction and anisotropy. Conversely, the film deposited at

α = 4 0^{\circ}

exhibited strong anisotropy and a non-Coulombic frictional response. Moreover, this film showed non-centrosymmetric behavior, requiring a non-linear model to accurately describe its frictional anisotropy.

采用单划痕试验研究了不同沉积角（α）下掠角沉积钼薄膜在不同载荷和方向下的摩擦行为。在α≥50°处沉积的薄膜形成椭圆柱状结构，由于方向相关的塑性变形而导致正交各向异性。增大沉积角度可提高柱间孔隙度，从而降低摩擦和各向异性。相反，在α=40°处沉积的薄膜表现出强烈的各向异性和非库仑摩擦响应。此外，该薄膜表现出非中心对称的行为，需要非线性模型来准确描述其摩擦各向异性。

引用次数: 0

Fractal tangential stiffness model of the joint surface considering stick–slip characteristics at asperity interfaces 考虑粗糙界面粘滑特性的节理面分形切向刚度模型

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-23 DOI: 10.1016/j.triboint.2026.111743

Hui Xiao , Yongsheng Zhao , Ying Li , Lele Liu , He Ma , Qiang Cheng , Zhifeng Liu

In high-end CNC equipment systems, the tangential stiffness of bolted joint surfaces is a key mechanical parameter governing assembly performance and dynamic stability. To address the limitation of conventional models in describing partial slip behavior at contact interfaces, this study proposes a tangential stiffness model for joint surfaces by analyzing the coupled evolution mechanism of adhesion and slip regions of asperities. First, based on the evolution of interfacial slip, a slip ratio is introduced as a key state parameter, and fractal tangential stiffness models for a single asperity and for the joint surface are established. By coupling the asperity size effect with the slip ratio, the multiscale deformation modes of the joint surface are revealed. On this basis, the influences of relevant parameters on tangential stiffness are systematically investigated. The results show that the tangential stiffness varies nonlinearly with the fractal dimension

D

and the slip ratio

s

, reaching a peak at approximately

D = 2.5

, and exhibiting fluctuations with changes in the fractal roughness

G

. An increase in the slip ratio effectively enhances the tangential stiffness, and this enhancement becomes more pronounced with increasing

D

. Finally, an experimental setup is established and comparisons with conventional models are performed, verifying the accuracy and applicability of the proposed model. The results provide theoretical support for contact performance analysis and assembly optimization of mechanical joint surfaces.

在高端数控设备系统中，螺栓连接面切向刚度是控制装配性能和动态稳定性的关键力学参数。为了解决传统模型在描述接触界面部分滑移行为方面的局限性，本研究通过分析接合面黏附区和滑移区耦合演化机制，提出了一种面向接合面的切向刚度模型。首先，基于界面滑移的演化规律，引入滑移率作为关键状态参数，建立了单个粗糙面和节理面的分形切向刚度模型；通过将粗糙体尺寸效应与滑移率耦合，揭示了节理面的多尺度变形模式。在此基础上，系统研究了相关参数对切向刚度的影响。结果表明，切向刚度随分形维数D和滑移比s呈非线性变化，在D=2.5左右达到峰值，并随分形粗糙度g的变化而波动。增大滑移比可有效增强切向刚度，且随着D的增大增强更为明显。验证所提出模型的准确性和适用性。研究结果为机械结合面接触性能分析和装配优化提供了理论支持。

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引用次数: 0

Self-reactive lubricating graphite-like coating for low-friction hydraulic energy converters 低摩擦液压能量转换器用自反应润滑类石墨涂层

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-23 DOI: 10.1016/j.triboint.2026.111749

Xiaolong Zhang , Kaiming Zheng , Junhui Zhang , Jianxiong Wu , Hongbin Lin , Xiaojiang Lu , Bing Xu , Chao Zhang

Hydraulic energy converters are components that can realize the conversion between mechanical energy and hydraulic energy. Their powers can be as high as 2 × 10⁶ W or more. For a high-power component, even if its efficiency is increased by 1 %, it will bring huge energy savings. However, current research mainly focuses on improving the efficiency of high-speed hydraulic energy converters via enhancing hydrodynamic effect, with little attention paid to low-speed hydraulic energy converters (<500 r/min). For that, this study develops a self-reactive lubricating graphite-like coating specifically for hydraulic energy converters to reduce mechanical friction that leads to low efficiency at low speeds. The self-reactive lubricating graphite-like coating is composed of two elements: carbon and tungsten. The results of the ring-block tests show that the coating with an atomic ratio (carbon: tungsten) of 0.51:0.49 has lower friction and temperature rise under three load conditions. Its mechanism is that an appropriate content of tungsten can react with additives in hydraulic oil to form a lubricating film, such as WS₂ and PO₃^-, thereby reducing friction. Afterwards, the preferred coating is applied to the pistons in a high-power cam-lobe hydraulic motor. The friction torque of the piston-roller friction pairs is tested on a homemade quasi-actual testing rig, and the results showed that the self-reactive lubricating graphite-like coating could reduce the friction torque by 14 %. The present study provides a new approach to improve the mechanical efficiency of hydraulic energy converters, and can also increase the starting torque to reduce the installed power.

液压能量转换器是能够实现机械能与液压能之间转换的部件。它们的功率可高达2 × 106 W或更多。对于一个大功率元件，即使其效率提高1 %，也将带来巨大的节能。然而，目前的研究主要集中在通过增强流体动力效应来提高高速液力能变换器的效率，而对低速液力能变换器（<500 r/min）的研究较少。为此，本研究开发了一种自反应润滑类石墨涂层，专门用于液压能量转换器，以减少导致低速低效率的机械摩擦。自反应润滑类石墨涂层由碳和钨两种元素组成。环块试验结果表明，碳钨原子比为0.51:0.49的涂层在3种载荷条件下具有较低的摩擦和温升。其机理是适当含量的钨能与液压油中的添加剂WS2、PO3-等反应形成润滑膜，从而减少摩擦。然后，将优选涂层应用于大功率凸轮叶液压马达的活塞上。在自制的准实际试验台上对活塞-滚子摩擦副的摩擦力矩进行了测试，结果表明，自反应润滑类石墨涂层可使摩擦力矩降低14% %。本研究为提高液压能量转换器的机械效率提供了一条新的途径，也可以通过提高起动转矩来降低安装功率。

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引用次数: 0

DLC-grease composite lubricating materials with ultra-low wear and ultra-high load capacity for wind turbine bearings 超低磨损、超高负荷风力发电机轴承用dlc -润滑脂复合润滑材料

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-23 DOI: 10.1016/j.triboint.2026.111746

Yahui Ren , Jiaying Zhang , Ming Zhang , Ao Xie , Zhenlin Yang , Wenquan Lv , Meirong Cai

A high-performance composite lubricant combining diamond-like carbon (DLC) films and customized grease was developed to address the rapid wear of DLC used as solid lubricants. Under contact stresses of 2.19–3.47 GPa, the composite reduced wear by 97.5%, achieving 1.10 × 10⁻⁸ mm³·N⁻¹·m⁻¹ after 288,000 cycles at 2.19 GPa. Using a DLC film with a dual transition layer enhanced adhesion and tribological performance. The composite forms a stable friction transfer oil film, while nano-additives in the grease further improve lubrication. This solid–liquid system offers low wear, long service life, and reduced maintenance frequency, demonstrating strong potential for wind turbine bearing applications.

为解决类金刚石（DLC）作为固体润滑剂的快速磨损问题，研制了一种结合类金刚石膜和定制润滑脂的高性能复合润滑剂。在2.19 GPa的接触应力为2.19 - 3.47 GPa时，复合材料的磨损降低了97.5%，在2.19 GPa下循环288,000次后达到1.10 × 10−8 mm3·N−1·m−1。采用具有双过渡层的DLC膜增强了附着力和摩擦学性能。复合材料形成稳定的摩擦传递油膜，而润滑脂中的纳米添加剂进一步提高了润滑性能。这种固液系统磨损小，使用寿命长，维护频率低，在风力涡轮机轴承应用中显示出强大的潜力。

引用次数: 0

Effect of the passivation oxide layer on the tribological properties of 316 austenitic stainless steel in B-Li solution 钝化氧化层对316奥氏体不锈钢在B-Li溶液中摩擦学性能的影响

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-23 DOI: 10.1016/j.triboint.2026.111748

Pijie Yu , Xuefang Chen , Tianxing Zhao , Yu Yan , Chengcai Li , Jinna Mei , Zhen Cai

To improve the wear resistance of the SUS 316 stainless steel surface, three different passivation treatments were explored, involving acid pickling, applied potential, and applied current density processes. The results indicated that the application of a constant potential yielded the optimal effect, with the optimal constant potential determined as 0.5 V. This was followed by the application of constant current density, while conventional acid pickling yielded the least favorable outcome. After passivation, fine precipitation phase could form, and a layer of precipitation phase was generated after repeated wear, which prevented further wear from occurring. However, excessive passivation, i.e., applying an excessively high current density or an overly high potential, could lead to the formation of pores on the surface. These pores could trap wear debris, causing direct abrasion between the debris and the bulk substrate of the specimens, leading to a deterioration in anti-wear performance.

为了提高SUS 316不锈钢表面的耐磨性，研究了三种不同的钝化处理方法，包括酸洗、施加电位和施加电流密度。结果表明，恒电位的应用效果最佳，确定最佳恒电位为0.5 V。其次是恒流密度的应用，而传统的酸洗效果最差。钝化后可形成细小的析出相，反复磨损后形成一层析出相，防止进一步磨损。然而，过度钝化，即施加过高的电流密度或过高的电位，可能导致表面形成孔隙。这些孔隙可能会捕获磨损碎屑，导致碎屑与试样基体之间的直接磨损，导致抗磨性能下降。

引用次数: 0

Microstructure and high-temperature tribological properties of WC/Fe functionally graded coating fabricated by laser directed energy deposition 激光定向能沉积WC/Fe功能梯度涂层的显微组织和高温摩擦学性能

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-23 DOI: 10.1016/j.triboint.2026.111744

Guangci Li , Yongcun Li , Yong Wang

This study addresses the issue of crack susceptibility in WC-reinforced iron matrix composite coatings at high WC contents by employing a functionally graded material (FGM) design. The aim is to enhance the allowable WC content limit and systematically investigate its effects on the coating’s microstructural evolution and high-temperature wear behavior. Single-composition and functionally graded WC/Fe composite coatings were fabricated on H13 steel substrates via laser-directed energy deposition (L-DED), with the WC content in the FGM coating progressively increasing from 0 to 30 wt% from the bottom to the top layer. The results demonstrate that the FGM coating remained crack-free at 30 wt% WC, whereas the single-composition coating exhibited significant macroscopic cracking at 20 wt% WC. With the increase in surface WC content, the lamellar interdendritic eutectic structure decreased, and M₇C₃-type carbides became the dominant phase. Additionally, Fe₃W₃C precipitates were formed in situ around WC particles via a peritectic reaction. Tribological tests revealed that at room temperature (RT), WC particles served as the primary load-bearing phase, and the wear mechanism was dominated by micro-fracture. At 400°C, thermal softening of the matrix promoted the formation of a lubricating layer from wear debris, shifting the wear mechanism to mild oxidative wear. The wear rate of the FGM coating was reduced by approximately 65 % compared to the WC-free coating. This study indicates that the FGM design effectively reconciles the contradiction between “high hardness” and “high crack resistance” in the coating, and significantly enhances its wear resistance by regulating the microstructure and high-temperature tribo-oxidation behavior.

本研究采用功能梯度材料（FGM）设计，解决了高WC含量WC增强铁基复合材料涂层的裂纹敏感性问题。目的是提高WC含量的允许极限，并系统地研究其对涂层显微组织演变和高温磨损行为的影响。采用激光定向能沉积（L-DED）技术在H13钢基体上制备了单组分和功能梯度WC/Fe复合涂层，涂层中WC含量从底层到顶层从0到30 wt%逐渐增加。结果表明，FGM涂层在30 wt% WC时无裂纹，而单组分涂层在20 wt% WC时出现了明显的宏观裂纹。随着表面WC含量的增加，层状枝晶间共晶结构减少，M₇C₃型碳化物成为主导相。此外，Fe₃W₃C沉淀物通过包晶反应在WC颗粒周围原位形成。摩擦学试验结果表明，常温下WC颗粒为主要承载相，磨损机制以微断裂为主。在400℃时，基体的热软化促进磨损碎屑形成润滑层，使磨损机制转变为轻度氧化磨损。与无wc涂层相比，FGM涂层的磨损率降低了约65% %。研究表明，FGM设计有效地协调了涂层中“高硬度”和“高抗裂性”的矛盾，并通过调节微观组织和高温摩擦氧化行为显著提高了涂层的耐磨性。

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引用次数: 0

Enhanced lubrication in water-lubricated bearings under low-speeds and heavy-loads via secondary lubricant 通过二次润滑剂，在低速和重载条件下增强了水润滑轴承的润滑

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-22 DOI: 10.1016/j.triboint.2026.111726

Qingchen Liang , Feng Guo , Peng Liang , Chunjiang Guo , Hao Ji , Xiaohan Zhang

To address severe friction challenges in water-lubricated bearings (WLBs) under complex and harsh operating conditions, a scheme is proposed that supplies a trace amount of secondary lubricant (SL) to the bearing within a short time. Preliminary experiments have demonstrated that this approach enhances hydrodynamic load capacity and optimizes the lubrication state of the WLBs. However, the correlation between the SL-assisted water lubrication and the diffusion of the two-phase flow under the low-speed and heavy-load working conditions remains unclear. Therefore, a theoretical model capturing interfacial diffusion of SL in WLBs is developed by coupling the Volume of Fluid (VOF) model with the mixed lubrication model, incorporating elastic deformation of bush and asperity contact. A numerical solver was developed and the calculation results indicate that a trace amount of SL can significantly reduce friction in WLBs under the low-speed and heavy-load conditions. It was shown that the oil injection volume of the SL can be determined in such a way to effectively mitigate its backflow at the entrance, enabling rapid migration of the SL to the contact area. This enhanced flow increases the oil-phase volume fraction in the contact area while reducing severe solid contact occurrences. This study provides a theoretical foundation for the design of WLBs.

为了解决水润滑轴承（WLBs）在复杂和恶劣的运行条件下的严重摩擦挑战，提出了一种在短时间内向轴承提供微量二次润滑剂（SL）的方案。初步实验表明，该方法提高了水动载荷能力，优化了wlb的润滑状态。然而，在低速和重载工况下，sl辅助水润滑与两相流扩散之间的关系尚不清楚。因此，将流体体积（VOF）模型与混合润滑模型相结合，建立了一个考虑轴瓦弹性变形和粗糙接触的混合润滑理论模型。计算结果表明，在低速和重载条件下，少量的SL可以显著降低wlb的摩擦。结果表明，通过这种方法可以确定SL的注油量，从而有效地缓解其在入口处的回流，使SL能够快速迁移到接触区域。这种增强的流动增加了接触区域的油相体积分数，同时减少了严重的固体接触。本研究为wlb的设计提供了理论基础。

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引用次数: 0

Enhancing the tribological performance of polyether ether ketone (PEEK) polymer using carbon-alloyed transition metal dichalcogenide coatings 采用碳合金过渡金属二硫化物涂层提高聚醚醚酮（PEEK）聚合物的摩擦学性能

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-22 DOI: 10.1016/j.triboint.2026.111739

Talha Bin Yaqub , Abbas AL-Rjoub , Irfan Nadeem , Parveen Kumar , Filipe Fernandes , Todor Vuchkov , Albano Cavaleiro , Mitjan Kalin

The demand for light-weight polymeric materials such as polyether ether ketone (PEEK) is increasing for advanced engineering components, like polymeric gears. However, the intrinsic limitations of PEEK, including high friction, poor wear resistance, and rapid surface degradation restrict its larger adoption. This work is dedicated towards enhancing the dry sliding performance of PEEK via surface modifications. Direct current magnetron sputtered (DCMS) carbon-alloyed tungsten disulfide (WSC) coatings having C content of ∼52 at. % were deposited on PEEK polymer substrates at low power. Modifications of coating architecture were obtained by depositing coatings with and without inter/gradient layers. Comprehensive post-deposition characterization included chemical composition, cross-section and surface morphology, crystal structure, detailed chemical bonding, and coatings-PEEK adhesion investigations. The coatings were uniform, compact, amorphous, and provided complete surface alteration of PEEK with sufficient coating-polymer adhesion. Under ambient air sliding, the WSC coating with inter/gradient layer architecture exhibited the best performance, by reduction in friction coefficient (COF) and specific wear rate up to ∼34.3 % and ∼98.3 %, respectively relative to the uncoated PEEK. Post sliding Raman and X-ray photoelectron spectroscopy (XPS) revealed that C dominated the role in the reduction of COF and wear through the formation of a stable, partially graphitized tribolayer. This work establishes a scalable pathway for integrating solid-lubricant coatings on polymeric components, opening new opportunities for their reliable use in high-load and energy-efficient industrial systems.

对聚醚醚酮（PEEK）等轻质聚合物材料的需求正在增加，以用于先进的工程部件，如聚合物齿轮。然而，PEEK的固有局限性，包括高摩擦、差耐磨性和快速表面降解，限制了其更大的应用。这项工作致力于通过表面改性来提高PEEK的干滑动性能。直流磁控溅射（DCMS）碳合金二硫化钨（WSC）涂层，其C含量为~ 52 at。%在低功率下沉积在PEEK聚合物衬底上。通过沉积有或没有间/梯度层的涂层，获得了涂层结构的改变。全面的沉积后表征包括化学成分、横截面和表面形貌、晶体结构、详细的化学键和涂层- peek粘合研究。涂层均匀，致密，无定形，并提供PEEK的完全表面改变，具有足够的涂层-聚合物附着力。在环境空气滑动下，具有间/梯度层结构的WSC涂层表现出最好的性能，相对于未涂层的PEEK，摩擦系数（COF）和比磨损率分别降低了~ 34.3% %和~ 98.3% %。滑动后拉曼和x射线光电子能谱（XPS）显示，C通过形成稳定的部分石墨化摩擦层，在减少COF和磨损方面起主导作用。这项工作为将固体润滑剂涂层集成到聚合物组件上建立了可扩展的途径，为其在高负载和节能工业系统中的可靠使用开辟了新的机会。

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引用次数: 0

SnNb2O6-enhanced PAO 10 lubrication for engineering steel: Insights from tribological experiments and simulations snnb2o6增强工程钢PAO 10润滑：来自摩擦学实验和模拟的见解

IF 6.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

Tribology International

Pub Date : 2026-01-22 DOI: 10.1016/j.triboint.2026.111740

Feizhou Li , Shuai Hu , Libin Lin , Yafeng Qi , Huan Wang

This study investigates the tribological enhancement of polyalphaolefin (PAO 10) lubricant for engineering steel through the incorporation of SnNb₂O₆ nanoparticles, combining experimental and molecular dynamics (MD) simulation approaches. Tribological tests reveal that adding SnNb₂O₆ at an optimal concentration of 0.3 % reduces the wear rate by 78.9 % under boundary lubrication conditions relative to neat PAO 10. The enhancement stems from the formation of a robust tribofilm, facilitated by strong adsorption of SnNb₂O₆ nanoparticles onto the steel surface, thereby reducing direct metal-to-metal contact and alleviating adhesive wear. The nanoparticles’ layered monoclinic structure (C2/c space group) and high surface area facilitate effective load-bearing and shear resistance. MD simulations provide atomic-scale insights, demonstrating that SnNb₂O₆ enhances the lubricant’s shear strength and load-carrying capacity by inducing ordered molecular alignment of PAO 10 chains. Mean square displacement analysis indicates comparable diffusion coefficients for PAO 10 and SnNb₂O₆, suggesting synergistic migration to the friction interface, enhancing film stability. The study also highlights the nanoparticles’ antibacterial properties, reducing colony counts of Escherichia coli and Staphylococcus aureus by disrupting bacterial cell membranes. These results highlight the pivotal influence of nanoparticle concentration and surface interactions in optimizing lubrication performance, offering a promising strategy for developing high-performance lubricants for engineering applications, particularly in high-load and precision machinery contexts.

本研究结合实验和分子动力学（MD）模拟方法，研究了SnNb2O6纳米颗粒对工程钢用聚α -烯烃（PAO 10）润滑剂摩擦学性能的增强作用。摩擦学试验表明，在边界润滑条件下，添加浓度为0.3 %的SnNb2O6比纯PAO 10的磨损率降低了78.9% %。由于SnNb₂O₆纳米颗粒在钢表面的强吸附，形成了坚固的摩擦膜，从而减少了金属间的直接接触，减轻了粘着磨损。纳米颗粒的层状单斜结构（C2/c空间群）和高比表面积有利于有效的承载和抗剪切。MD模拟提供了原子尺度的见解，表明SnNb2O6通过诱导PAO 10链的有序分子排列来提高润滑剂的剪切强度和承载能力。均方位移分析表明，PAO 10和SnNb2O6的扩散系数相当，表明协同迁移到摩擦界面，增强了膜的稳定性。该研究还强调了纳米颗粒的抗菌特性，通过破坏细菌细胞膜来减少大肠杆菌和金黄色葡萄球菌的菌落计数。这些结果强调了纳米颗粒浓度和表面相互作用对优化润滑性能的关键影响，为开发高性能工程润滑油提供了有前途的策略，特别是在高负荷和精密机械环境中。

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引用次数: 0