第三讲 固体润滑膜的制备

第三讲　固体润滑膜的制备常州牵引电机厂石淼森关键词固体润滑膜，制备，粉末喷涂，复合镀层将固体润滑剂粘结在摩擦表面上的方法较多。例如将固体粉末直接飞溅（在齿轮箱内），以及采用各种物理或化学方法粘着等。在固体润滑技术领域内，通常采用下列几种方法：即所谓干...     

六.防锈、润滑

固体润滑译文集广州热带机床研究所借阅号:5.54/23 内容有:固体和固体润滑;固体润滑剂的应用;影响树脂粘结固体膜润滑剂使用性能的因素;二硫化钼对各种金属的润滑;各种润滑剂和基底材料对摩擦和超高负荷的影响;民主德国使用二硫化钼润滑剂的概况;关于二硫化钼润滑机理的新见     

固体润滑剂的特性及其应用

固体润滑剂具有许多良好的特性，其在各种机械中的应用日益广泛。本文主要介绍固体润滑剂的特性及其应用场合。一、团体润滑剂的特性不管是以固体粉末直接擦抹于摩擦表面，还是用无机或有机粘结剂将其粘结于摩擦表面或是用物理或化学方法钦覆于摩擦表面，进人际接到间的固体润滑剂是以固体润滑膜的形式发挥其作用的，因而都具备以下特性。1．摩擦特性粘着于摩擦表面的固体润滑剂在与对倡材料摩擦时，在对偶材料表面形成转移膜，使摩擦发生在润滑剂内部．这样才能表现出良好的摩擦特性——较低的摩擦系数。而且，摩擦系数随着负荷和速度的增…     

基于面接触的粉末润滑实验研究

利用石墨粉末颗粒,基于端面摩擦试验机对粉末润滑方式开展了摩擦学研究。试验了粉末冶金铜合金材料、粘结石墨润滑涂层、PTFE 3层自润滑复合材料3种试样在石墨粉末颗粒流润滑条件下的摩擦因数、温度及表面膜等特性,并与干摩擦和油润滑进行了对比。结果表明:粉末润滑可以实现与固体润滑膜、自润滑材料类似的无油固体润滑效果;利用它的持续补充性,可以实现动态补充和修复的固体润滑膜;但是,粉末润滑膜与基体附着能力较差。     

固体润滑剂应用的研讨

论述了固体润滑膜的干法制备、湿法制备、粉末喷涂、复合镀和涂擦成膜等方法的工艺及配方；固体润滑剂在压力加工、齿轮、导轨、气缸与活塞、轴承等方面应用；固体润滑剂做成背衬型材料、镀嵌型材料、油脂中添加固体润滑剂等的特性与应用．     

粘结固体润滑膜及其润滑特性

在历史上选择固体用于润滑大概有几百年了。但是,粘结固体润滑膜技术的研制仅在三十多年前才开始的。早先的粘结固体膜润滑剂(BSLF)是由MoS_2或石墨同磷酸、玉米糖浆、酚醛树脂等粘结材料组成的,其应用范围受一定的限制。由于现代工业的发展(如宇宙航行,海洋开发)对润滑技术提出耐高低温、抗腐蚀、耐辐射、能在真空与特     

固体润滑剂在轴承上的应用研究

以水轮发电机轴承为应用研究实例，介绍了轴承镶嵌固体润滑剂的摩擦磨损机理，镶嵌轴承套的结构，固体润滑剂材料；并用摩擦学性能试验及台架模拟试验验证；在水轮发电机轴承上使用固体润滑剂可以提高润滑性能、降低摩擦系数，使摩擦副间能不断形成自补偿固体润滑转移膜，说明在重载，低速，摆动，间歇运动和泥水环境苛刻条件下工作的水轮发电机轴承使用固体润滑剂，比液体润滑具有更优越的性能。     

表面织构对二硫化钼喷涂膜摩擦学性能的影响研究

在试件表面激光加工表面织构,采用喷涂法制备二硫化钼固体润滑膜,在环块摩擦磨损试验机上研究沟槽型表面织构对二硫化钼固体润滑膜的摩擦学性能的影响。结果表明,在一定的工况条件下,就固体润滑膜的寿命而言,微沟槽的几何参数存在最优值。分析发现,织构可以储存固体润滑剂,在一定的工况条件下,会使得织构内的固体润滑剂被挤出,不断地补充摩擦接触面间的固体润滑剂,使得固体润滑膜的寿命延长。     

表面织构对二硫化钼喷涂膜摩擦学性能的影响

在试件表面激光加工表面织构,采用喷涂法制备二硫化钼固体润滑膜,在环块摩擦磨损试验机上研究沟槽型表面织构对二硫化钼固体润滑膜的摩擦学性能的影响。结果表明,在一定的工况条件下,就固体润滑膜的寿命而言,微沟槽的几何参数存在最优值。分析发现,织构可以储存固体润滑剂,在一定的工况条件下,会使得织构内的固体润滑剂被挤出,不断地补充摩擦接触面间的固体润滑剂,使得固体润滑膜的寿命延长。     

二硫化钼固体润滑性能及其应用

详细介绍了二硫化钼的结构特点以及作为固体润滑减磨材料的原理.综述了二硫化钼作为固体润滑的粘结型固体润滑膜、沉积型固体润滑膜这两种固体润滑膜的性能及工艺特点,并介绍了它们在工业上的应用及其发展现状.     

Tribological performance of graphite containing tin lead bronze-steel bimetal under reciprocal sliding test

As a solid self-lubricating material to serve under heavy load and low velocity, graphite containing tin lead bronze-steel bimetal composites were prepared using the powder metallurgy (P/M) technique. Effects of graphite content on tribological performance under reciprocal sliding were studied using the UMT-2MT tribo-meter. The optimal performance of average friction coefficient, maximum friction coefficient, friction coefficient amplitude and wear resistance can be achieved at the graphite content of ∼3 wt%. Appropriate graphite content and hardness are the two most crucial factors to achieve a good quality lubricating film on the worn surface and hence the desired solid lubrication performance.     

Effect of electrical current on the tribological behavior of the Cu-WS2-G composites in air and vacuum

As the traditional graphite-based composites cannot meet the requirement of rapid developing modern industry, novel sliding electrical contact materials with high self-lubricating performance in multiple environments are eagerly required. Herein a copper-based composite with WS2 and graphite as solid lubricant are fabricated by powder metallurgy hot-pressed method. The friction and wear behaviors of the composites with and without current are investigated under the condition with sliding velocity of 10 m/s and normal load of 2.5N/cm 2 in both air and vacuum. Morphologies of the worn surfaces are observed by optical microscope and compositions of the lubricating films are analyzed by XPS. Surface profile curves and roughness of the worn surfaces are obtained by 2205 surface profiler. The results of wear tests show that the friction coefficient and wear volume loss of the composites with current are greater than that without current in both air and vacuum due to the adverse effects of electrical current which damaged the lubricating film partially and roughed the worn surfaces. XPS results demonstrate that the lubricating film formed in air is composed of oxides of Cu, WS2 , elemental S and graphite, while the lubricating film formed in vacuum is composed of Cu, WS2 and graphite. Because of the synergetic lubricating action of oxides of Cu, WS2 and graphite, the composites show low friction coefficient and wear volume loss in air condition. Owing to the fact that graphite loses its lubricity which makes WS2 become the only lubricant, severe adhesive and abrasive wear occur and result in a high value of wear rate in vacuum condition. The formation of the lubricating film on the contact interface between the brush and ring is one of the factors which can greatly affect the wear performance of the brushes. The low contact voltage drop of the composites in vacuum condition is attributed to the high content of Cu in the surface film. This study fabricated a kind of new sliding electrical contact self-lubricating composite with dual-lubricant which can work well in both air and vacuum environments and provides a comprehensive analysis on the lubrication mechanisms of the composite.     

Torsional Fretting Wear Behavior of Bonded MoS2 Solid Lubricant Coatings

The effects of applying a bonded MoS₂ solid lubricant to a 1050 steel substrate were investigated using a torsional fretting wear apparatus. Tests were conducted under a normal load of 50 N with angular displacement amplitudes ranging from 0.1 to 5°. Wear scars were examined using scanning electron microscopy, energy-dispersive X-ray spectrometry, optical microscopy, and surface profilometry. The MoS₂ coating exhibited different torsional fretting regimes than those of the substrate. Fretting regimes of the coating were primarily in the partial slip regime (PSR) and the slip regime (SR) with no mixed fretting regime. The width of the PSR narrowed. Due to the lubricating effects of the coating, the friction torque was consistently lower than that of the substrate. The damage to the coating in the PSR was very slight, and its granular structure remained even after 1,000 cycles. The damage mechanism to the SR coating was a combination of abrasive wear, oxidative wear, and delamination. The MoS₂ coating had potential to alleviate torsional fretting wear.     

石墨含量对铜基石墨自润滑复合材料摩擦过程中石墨润滑膜的影响

为研究石墨含量对铜基石墨自润滑复合材料摩擦过程中形成石墨润滑膜的影响,采用粉末冶金法制备了不同石墨含量的铜基石墨自润滑复合材料,测试了复合材料的力学性能,用自制环-块摩擦试验机测试评估了材料的耐磨性能,用光学显微镜实时原位观察了摩擦表面组织形貌的变化,用扫描电镜对磨痕进行观察和分析,通过能谱仪成分扫描分析接触面石墨润滑膜的覆盖率。结果表明:随着复合材料中石墨含量的增加,材料的力学性能逐渐降低,石墨润滑膜的覆盖率先升高后降低,磨损量先减小后增大;当石墨体积分数为14%时,石墨润滑膜的覆盖率最高,磨损量最小,耐磨性能最好。     

粘结MoS2固体润滑涂层的转动微动磨损特性

采用粘结法在LZ50钢表面制备MoS2固体润滑涂层,研究MoS2涂层及LZ50钢基体在干态不同角位移幅值下的转动微动磨损行为。在分析转动微动动力学特性的同时,结合光学显微镜、扫描电子显微镜、电子能谱仪以及轮廓仪对磨痕形貌进行微观分析。结果表明:涂层和基体的转动微动运行区域仅呈现部分滑移区(Partial slip regime,PSR)和滑移区(Slip regime,SR),未观察到混合区。涂层改变基体的微动运行区域,使得PSR缩小,SR运行区域向小角位移幅值方向移动。由于MoS2涂层的固体润滑作用,涂层的摩擦因数在整个试验过程都明显低于基体。在PSR,涂层损伤轻微;在SR,涂层的转动微动磨损机制主要表现为剥层和摩擦氧化。研究表明粘结MoS2固体润滑涂层具有明显的防护作用,显著降低LZ50钢的转动微动磨损。     

Fretting wear behaviors of nanometer Al2O3 and SiO2 reinforced PEEK composites

The influence of diameter and content of Al₂O₃ particles on the tribological behaviors under fretting wear mode was investigated. The surface of PEEK composite and steel ball were examined by SEM and EDS, to identify the topography of wear scar and analyze the distribution of chemical elements in the friction counterparts, respectively. It can be found that the filling of Al₂O₃ powder improves the fretting wear resistance of PEEK composite. With the increase of Al₂O₃ diameter, the area of wear scar on specimen increases first and decreases afterward. However, the wear of composites increases monotonically with increasing Al₂O₃ content. Although the filling of 10 wt.% and 200 nm PTFE powder in PEEK makes the lowest wear of all specimens, no synergistic effect was found when Al₂O₃ and PTFE were filled into PEEK composite together. For the friction pair of PEEK composite and steel ball, abrasive wear and adhesive wear dominate the fretting wear mechanism during fretting. Thermal effect plays a very important role during fretting; thus the property of temperature resistance for polymer material would affect the wear degree on the surface of wear scar.     

固体润滑涂层在干摩擦及有油条件下的摩擦磨损性能

采用MRH-3环块磨损试验机对FM-510二硫化钼润滑涂层在于摩擦及有油条件下进行了摩擦磨损性能的考察和评价,评价结果表明：该涂层在干摩擦条件下具有低的摩擦系数、高的承载能力和长的耐磨寿命,摩擦系数随负荷增高而降低,随速度提高也降低。摩擦偶对双面涂膜比单面涂膜有更长的耐磨寿命,速度低时涂层的磨耗小,寿命长,可满足特定条件下的干摩擦工作要求,在有油润滑条件下二硫化钼基的FM-510润滑涂层可显减轻对偶磨损程度,摩擦系数比单独使用油润滑时大大降低。在难以形成连续的流体润滑薄膜,亦即不能形成流体动力润滑的情况下。摩擦偶对涂敷固体润滑涂层是解决其润滑问题的有效方案。     

Theory of Life Prediction of a Viscoelastic Lubricating Surface Film

A solid lubricating surface film is modeled as a general linear viscoelastic material. The appropriate governing equations are solved for the displacement of such a thin film under repeated loadings. The predicted transient motion of the surface is monitored. The gradual diminution of the lubricant film thickness under repeated loadings is considered film wear. The failure of solid lubricating film occurs when the existing thickness is to the same order of magnitude as the substrate surface roughness.     

On the behaviour of an oil lubricated fretting contact

Although many engineering situations involving fretting damage are lubricated, comparatively little has been reported on this aspect of fretting wear. The viscosity of the lubricating oil and its boundary layer performance are expected to influence fretting behaviour, in addition to the normal fretting parameters, such as stroke and contact force.

This paper examines the effect of lubrication regime, oil viscosity and stroke on the behaviour of a ball-against-flat specimen arrangement. Ball and flat specimens were both manufactured from a bearing steel (SUJ2). Polybutane oils, without additives, covering a range of viscosities from 1 to 10 000 cSt, and fretting strokes up to 35 μm were investigated. The lubricating oil was added to the fretting interface after 0, 3 and 2000 fretting cycles had been completed. Lubrication regime, oil viscosity and stroke were all found to affect fretting behaviour in terms of both coefficient of friction (or traction coefficient) and wear. For strokes less than 9 μm, i.e. for conditions approaching almost complete ‘stick’, coefficient of friction values under oil lubrication were well in excess of double those observed without it. These high values suggest that the oil was unable to penetrate into the fretting contact region, but did maintain a shield around it, so that metal-on-metal contact was maintained under oxygen deprived conditions. The lowest values of steady state coefficient of friction (≈ 0.2) were observed when oil lubrication was applied after 2000 cycles had been completed, indicating that surface roughening and the presence of oxide films and oxidised debris assisted penetration of the lubricant into the fretting contact zone.     

Prediction of fretting wear using boundary element method

The simulation method of the fretting wear prediction using boundary element method is developed. The contact pressure and the contact width which is the first step to predict fretting wear are obtained from contact analysis of a semi-infinite solid based on the use of influence functions and patch solutions. The geometrical updating is based on nodal wear depths computed using Archard’s equation for sliding wear. The prediction of fretting wear for two cases of contact problems is performed; one is two-dimensional cylinder on flat contact which is for the comparison with a previous model by finite element method; the other is three-dimensional spherical contact. It is observed that for two-dimensional cylindrical contact the boundary element method developed in this study reduced the calculation time by 1/48 compared to FE method. We also showed the use of developed simulation technique is efficient to predict the fretting wear for three-dimensional spherical contact.