Effect of Fluorides and Cerium Dioxide Additives onEP and Antiwear Performance of Grease

CeF3. CaF2, (CF)n, SbF3, and CeO2 were selected as the high temperature solid additives in a lithium grease, and their friction, wear, and extreme pressure properties were evaluated on an Optimol-SRV wear tester. The effect of additive on the fiber structure of soap was studied by means of the transmission electron microscopy(TEM). The corrosive property of grease containing additive was evaluated by copper strip corrosion test. Thermal decomposition behaviors of the additives were studied by thermogravimetry(TG) tester. The adhesive strength of rubbing surface film was measured by automatic scratch tester and the wear surface was detected by means of X-ray photoelectron spectroscopy (XPS). The test results showed that the grease containing CeF3 has good anti-wear, anti-friction, and EP performances, and has high adhesive strength of rubbing surface film.The greases containing CaF2 or (CF)n are good in antiwear and anti-friction properties, but poor in extreme pressure function. The tribological properties of the grease containing SbF3 are decreased.And the addition of CeO2 in grease was useless. Finally the mechanism of fluoride additive was proposed in this paper.

Competitive Adsorption of Anticorrosion and Antiwear Additives

Simulated adsorptive experiments using the axletree and lubricating oil containing anticorrosion additive were conducted,and the UV absorbance of the lubricating oil before and after the adsorptive experiments was measured.Through the UV spectral measurements the difference in UV absorbance of the lubricating oil before and after the adsorptive experiments was identified,the adsorbed quantity of anticorrosion additive in the interfacial film between lubricating oil and bearing was calculated using the Lambert-Bell principle to verify the adsorption of corrosion inhibitor on the surface of friction pairs.Adsorption experiments on lubricating oil containing both antiwear and anticorrosion additives were carried out and the UV absorbance of lubricating oil samples before and after the experiments was measured to determine the difference in the UV absorbance among lubricating oil samples with the same mass fraction of anticorrosion additive and different mass fractions of antiwear additive.By measuring the ultraviolet spectral absorbance of lubricating oil samples and calculating the adsorbed quantity of anticorrosion additive in the interfacial film it was possible to determine the influence of antiwear additive on the quantity of adsorbed anticorrosion additive on the surface of friction pairs and verify the competitive adsorption relationship between the antiwear additive and the anticorrosion additive.

Tribological behaviour of oil-soluble organo-molybdenum compound as lubricating additives

A four-ball machine was employed to investigate the tribological performances and the synergetic function of organo-molybdenum compounds (molybdenum dialkyl-dithiophosphate and molybdenum dithiophosphate, coded as MoDDP and MoDTP, respectively) as additives in liquid paraffin. The morphologies of the worn surfaces and elemental distributions were observed and determined by means of scanning electron microscopy and energy dispersive spectrometry. The chemical states of some typical elements on the worn surface were analyzed on X-ray photoelectron spectroscope. The results show that MoDDP and MoDTP additives in liquid paraffin have excellent antiwear and friction-reduction properties, which are attributed to the reaction film composed of MoS2, FeS and MoO2, and the deposited film composed of phosphate on the worn surface. Moreover, these two additives have synergetic friction-reducing and antiwear effect, which is closely related to the chemical states of S on the worn surface.

High temperature tribological behaviors of nano-diamond as oil additive

The tribological behaviors of the nano-diamond particles including the nano- diamond and the nano-diamond modified were studied at high temperature using SRV multifunctional test system. The worn steel surfaces were analyzed by means of X-ray photoelectron spectroscopy (XPS). The results show that nano-diamond particles can obviously improve the antiwear and friction reducing properties of the base oil at high temperature and the high load. The friction coefficient of the nano-diamond is very low at 200 ℃ when the test load is not more than 20 N. This tribological behaviors should attributed to the similarly to “ball bearing” lubrication action of the nano-diamond particles, so the movement between tribological pairs become sliding/rolling. The nano-diamond modified by dimer ester possesses excellent antiwear and friction reducing performance at 500 ℃ and load 500 N. The tribochemical reaction film between the nano-diamond particles and the renascent wear surface plays dominating lubrication role and the presence of the dimer ester on the rubbing surface can be propitious to form lubrication film containing nano- diamond on the worn surface at high temperature and high load.

Tribological performance of organic cadmium compound as lubricant additive

The oil-soluble cadmium dipropyldithiophosphate additive was synthesized. A four-ball tester was used to evaluate the tribological performance of the additive in a mineral oil under different loads and lubricant grease synthesized compared with some commercial additives. The results show that it exhibits excellent antiwear and load-carrying capacities and is better than other additives. The surface analytical tools such as scanning electron microscope (SEM) with energy dispersive X-ray (EDX), X-ray photoelectron spectrometer (XPS) were used to investigate the topography, the compositions, and chemical states of some typical elements on the rubbing surface of worn scar.Smooth and light topography of worn scar further confirms that the additive shows good antiwear capacities. The results of EDX and XPS analyses indicate that tribochemical mixed protective films consisting of atomic cadmium, sulphides, sulphates and phosphates are formed on the rubbing surface, which contribute to improving the tribological properties of lubricant and grease. Particularly, the soft cadmium film formed plays an important role in improving antiwear properties of oils. Finally, antiwear mechanism of the additive and formation scheme of atomic cadmium was proposed.

Antiwear and reducing friction performance of (2-sulphurone-benzothiazole)-3-methyl dodecanoate

A heterocyclic derivative of (2 sulphurone benzothiazole) 3 methyl dodecanoate was synthesized. Its tribological performance when added to liquid paraffin was evaluated on a four ball tester and a ring on block machine. Results indicate that compared with the base oil the wear resistance and load carrying capacities of the oil with novel additive are improved, and the friction coefficient is decreased. There is an optimal content of the novel compound, at which the corresponding oil gives the highest maximum non seizure load. Above the content, the load carrying capacity of the oil is not increased but decreased. The nature of the film formed on the rubbed surface was investigated by X ray photoelectron spectroscopy (XPS) analysis, and the action mechanism of the novel compound was discussed. [

巯基苯并噻唑类离子液体在酯类润滑油中的抗氧化性能及摩擦学性能研究

本文中合成两种季鏻盐巯基苯并噻唑类离子液体,以传统多功能添加剂ZDDP为参照,对比考察离子液体在酯类润滑油中的抗氧化性能和摩擦学性能.旋转氧弹测试结果表明,两种多功能离子液体能够显著提升酯类油的氧化诱导期,且效果优于ZDDP,表现出优异的抗氧化性能;摩擦学测试结果表明,两种离子液体都能够降低酯类油的摩擦系数和磨损量,表现出优异的减摩抗磨性能.磨损表面分析发现,摩擦过程中离子液体在表面发生摩擦化学反应,生成具有低剪切性能的含S摩擦化学产物,进而起到减摩抗磨作用.所合成的季鏻盐巯基苯并噻唑类离子液体兼具抗氧化性能和减摩抗磨性能,是一种可用于酯类润滑油的多功能添加剂.

噻二唑衍生物润滑油添加剂研究进展

综述了近年来噻二唑衍生物润滑油添加剂的研究进展。主要介绍了含黄原酸结构的噻二唑衍生物添加剂、含二硫键结构的噻二唑衍生物添加剂、硼酸酯(盐)类噻二唑衍生物添加剂、含酰胺结构的噻二唑衍生物添加剂、噻二唑希夫碱添加剂、含酯或醚结构的噻二唑衍生物添加剂等一系列单一噻二唑润滑油添加剂。此外,还介绍了纳米颗粒与噻二唑衍生物的复合润滑油添加剂,该类复合润滑油添加剂能够显著提高润滑油基础油的摩擦性能。提出了制备油酸型噻二唑衍生物润滑油添加剂、噻二唑类离子液体润滑油添加剂及噻二唑纳米微粒润滑油添加剂的展望。

PAO3基磁性流体的摩擦学性能研究

制备了以Fe_(3)O_(4)为磁性纳米粒子的航空基础油(PAO3)基磁性液体,通过X射线透射仪(XRD)、场透射电镜(TEM)、震动磁强计(VSM)和静置试验对其进行表征,并将其作为润滑油进行研究.与基础油PAO3进行对比,共同考察了在不同摩擦对偶上的摩擦学性能.通过扫描电子显微镜(SEM)、能谱仪(EDS)、轮廓仪和光学显微镜,测试了其在12CrNi4A钢/304钢、12CrNi4A钢/GCr15钢和12CrNi4A钢/Si3N4陶瓷摩擦副上的摩擦学性能,探究了其润滑机理.结果表明:所制备的磁性液体能够稳定分散,满足磁性液体标准.相比于基础油,磁性液体的摩擦学性能受到多因素的影响,在一定条件下具有优异的减摩和抗磨性能.这主要归因于纳米Fe_(3)O_(4)粒子对摩擦副表面氧化膜的去除与修复以及浓度和磁场对其分散性与团聚性的影响.

航空润滑油防锈性能研究

采用湿热试验和液相锈蚀试验方法考察了酯类基础油、防锈剂和极压抗磨剂对航空润滑油防锈性能的影响。结果表明己二酸酯、三羟甲基丙烷酯和季戊四醇酯基础油均不具备良好的防锈性能;防锈剂的加入能改善基础油的防锈性能,不同种类的防锈剂所表现出的防锈效果差异很大,含氮化合物和羧酸类防锈剂的防锈效果远大于酯类防锈剂;极压抗磨剂的加入降低了航空润滑油的防锈性能,极压抗磨剂含量增加,防锈性能随之变差,硫代磷酸三苯酯(TPPT)抗磨剂比磷酸三甲酚酯(TCP)抗磨剂对防锈性能的抑制作用更明显。

二烷基二硫代磷酸锑的合成及性能研究

文章研究了二烷基二硫代磷酸锑的合成工艺,通过考察反应时间、反应温度、投料方式、催化剂、原材料规格等,得出了最佳合成工艺,制备出了纯度较高、比值(碱式盐∶中式盐)适中的二烷基二硫代磷酸锑产品。对不同纯度、不同比值(碱式盐∶中式盐)的产品进行了抗氧、抗腐、极压、抗磨等性能评价,结果表明,纯度越高,产品的抗氧、抗腐、极压、抗磨性能越好,但油溶性和纯度没有明显对应关系。得出了产品中碱式盐与中式盐比值的最佳范围为0.84~1.30,为其应用提供了参考。

含纳米铜的减摩修复添加剂摩擦学性能及其作用机理研究

在不同条件、不同接触形式下考察了含钠米铜的减摩自修复添加剂的摩擦学性能,以及对不同油晶的影响规律。结果表明,添加剂NFR2具有优良的减摩抗磨性能,用于液体石蜡、16号坦克油和15W/30油中,磨斑直径分别降低了42％、56％和19％,摩擦系数分别降低了50％、49％和33％。其修复性能试验后,出现了负增重现象。而添加剂NFR1具有良好的高温抗磨减摩性能,用于16号坦克油中,磨损降低了56％,摩擦系数降低了27％。其热管氧化情况与16号坦克油空白试验相似。XPS、SEM等表面技术分析结果表明,摩擦表面生成含Mo、S、P和O等元素的摩擦化学反应膜,其中Mo主要以+6价形式存在,元素S主要以-2价和+6价形式存在,元素P主要以+5价形式存在。

表面修饰硼酸盐润滑油添加剂的摩擦学性能

制备了表面修饰的硼酸盐润滑油添加剂（球形颗粒，粒径大都小于０．５μｍ），且用四球试验机研究了其摩擦学性能．结果表明：这种添加剂具有良好的极压抗磨减摩性能，当润滑油中元素Ｂ的质量分数为０．０５％时，四球磨斑直径最小，最大无卡咬负荷（ｐＢ值）最高；基础油的粘度和含水量对添加剂的极压抗磨性能有较大的影响，粘度为６５．３０ｍｍ２／ｓ时的极压抗磨性最好，水的质量分数为１％时的ｐＢ值最高，低于１％时的ｐＢ值比不含水时的高，水的质量分数高于１％时的ｐＢ值随水含量的增加而降低．Ｘ射线光电子能谱分析发现，表面修饰的硼酸盐润滑油添加剂在摩擦表面形成了一层混合的摩擦化学反应膜，其中元素Ｂ主要以ＢＮ的形式存在．

二氧化钛纳米微晶的制备及性质的研究

用无水四氯化铁和异丙醇为原料，用溶胶－凝胶法制备二氧化钛纳米微晶，用一系列手段研究了它的结构。结果表明，所得纳米微晶为椭球状，粒径分布范围窄，６００℃焙烧１小时所得微晶为锐钛矿相和金红石相两种结构共存，其Ｘ射线光电子能谱及红外光谱的特性直接受该微结构的影响。

纳米铜润滑油添加剂的摩擦磨损特性及其机理研究

设计了4种试验方案,对比研究了不同摩擦试验条件下粒径为20 nm的铜添加剂对摩擦副的修复作用,考察了纳米铜添加剂在不同润滑油中的抗磨减摩性能,探讨了纳米铜添加剂的作用机理.结果表明:在摩擦过程中,纳米铜添加剂能够在磨损表面形成由粒径为0.1μm团状物构成、低剪切强度的保护软膜,可以减小粘着磨损和磨粒磨损,使纳米铜添加剂表现出良好的抗磨减摩性能;对于基础润滑油650SN,纳米铜添加剂能够使其摩擦系数降低48%、磨痕宽度降低21%;对于坦克机油50CC,纳米铜添加剂能够使其摩擦系数降低40%、磨痕宽度降低33%;同时,铜保护膜修复了磨损表面的微坑和损伤,对摩擦副起到了有效的保护和修复作用.

硼酸钾做润滑油添加剂的抗磨性能之研究

作者利用Shell-Seta四球试验机研究了白油中所含硼酸钾的抗磨特性,以及分散刘中性烷基苯磺酸钙对硼酸钾抗磨性能的影响,并且利用X-射线光电子能谱仪(XPS)和俄歇电子能谱仪(AES)考察了摩擦表面的元素组成及硼元素的价态。结果表明,含硼酸钾的白油能够在摩擦表面形成含硼酸钾的表面膜而具有较好的抗磨性,硼在摩擦表面膜中以硼酸钾的形式存在,分散剂烷基苯磺酸钙会影响硼酸钾沉积腆的形成及其与金属表面的结合强度而降低抗磨性能。

含纳米金刚石复合润滑油添加剂的摩擦学性能

研究了表面改性的纳米金刚石分别与硫磷丁辛基锌盐和磷氮剂等功能添加剂复配的相互作用，含纳米金刚石复合添加剂的摩擦性能，以及含改性纳米金刚石复合添加剂与几种商品添加剂摩擦性能的比较。结果表明，表面改性的纳米金刚石与硫酸丁辛基锌盐和磷氮剂等功能添加剂之间存在协同效应，含纳米金刚石的复合润滑油添加剂具有优异的极压抗磨减摩性能。

油溶性有机钼添加剂的摩擦学性能及其摩擦化学作用机制

采用四球摩擦磨损试验机考察了2种油溶性有机钼添加剂2 乙基己基 二硫代磷酸氧钼(MoDDP)和硫化 二异丙基 二硫代磷酸钼(MoDTP)的摩擦学性能及其复配体系的抗磨减摩性能,采用扫描电子显微镜和X射线光电子能谱仪分析了磨斑表面形貌和表面膜元素组成,探讨了有机钼添加剂的摩擦化学作用机制.结果表明,有机钼添加剂MoDDP和MoDTP均具有优异的摩擦学性能,其复配体系呈现协同抗磨减摩效应,这是由于有机钼添加剂在摩擦副表面形成由FeS、MoS2及MoO2组成的化学反应膜和由含磷化合物组成的沉积膜所致.

极压、抗磨剂对锂基润滑脂抗磨减摩性能的影响

采用四球和SRV试验机分别考察了不同浓度的3种添加剂（T321,TCP和T202）在不同酸碱性的锂基润滑脂中的极压、抗磨性;并分别采用扫描电子显微镜和X射线光电子能谱仪观测钢球的磨斑表面形貌和分析钢球磨斑表面的主要元素。研究发现,在适宜的酸碱性下,硬脂酸对含3种添加剂的锂基润滑脂的抗磨、极压性有增效作用。添加3%T202或1%~2%T321或2%TCP的弱酸性锂基润滑脂相应的摩擦系数最低、磨斑直径最小、磨损量最少、PD或PB值较高。而且,含3种不同添加剂的锂基润滑脂润滑下的钢球磨斑形貌有明显区别,其减摩抗磨机制为在摩擦表面生成含硫、磷、锌等元素的化学沉积膜。

表面修饰SiO_2纳米微粒作为液体石蜡添加剂抗磨性能的研究

用原位表面修饰法合成了异辛酸修饰SiO2纳米微粒,利用四球摩擦磨损试验机考察了SiO2纳米微粒作为液体石蜡添加剂的摩擦学行为。用扫描电子显微镜(SEM)和X射线光电子能谱仪(XPS)对钢球磨损表面进行了分析。试验结果表明,SiO2纳米微粒作为液体石蜡添加剂具有良好的抗磨损性能,能显著提高液体石蜡的失效载荷;表面修饰SiO2纳米微粒在摩擦过程中发生了摩擦化学反应,形成了含SiO2及有机分解产物等组分的复合边界润滑膜,从而表现出良好的抗磨性和较高的承载能力。