Enhanced Anti-Wear Property of Low Viscosity Engine Oil for Sequence IVB Engine Test Meeting the GF-6 Specification

The purpose of this research is to determine the anti-wear capability of new advanced low viscosity engine oil to meet the Sequence IVB requirement of ILSAC GF-6 specification, which envisages that the first certification will be realized in 2020. The anti-wear performance of the aged candidate GF-6 engine oils was evaluated using the laboratory bench test rigs such as the Falex Pin & Vee Block test machine and the high frequency reciprocating rig (HFRR). The worn surfaces were analyzed by X-ray photoelectron spectroscopy (XPS). The remarkable anti-wear performance of the developed GF-6 engine oil was also confirmed in the Sequence IVB test. The results indicate that by appropriately selecting and balancing the calcium detergent additives the wear loss of cam and tappet determined in the Sequence IVB test at low temperature could be significantly reduced. The time for occurrence of the intersection of the base and acid values corresponds well with the increase of wear of cam tappet of the IVB engine test.

Tribological Testing of Hemispherical Titanium Pin Lubricated by Novel Palm Oil:Evaluating Anti-Wear and Anti-Friction Properties

In this study, the properties of hip implant material and lubricants were examined using a pin on disc apparatus, to compare the effect of metal-on-metal （MoM） contact with a bio-lubricant derived from palm oil. The behaviour of the lubricants was observed during the experiments, in which a hemispherical pin was loaded against a rotating disc with a groove. A titanium alloy was used to modify the hemispherical pin and disc. Before and after the experiments, the weight and surface roughness were analysed, to detect any degradation. The results were compared according to the different kinematic viscosities. The wear rates and level of friction with each lubricant were also examined. The lubricant with the highest vis- cosity had the lowest frictional value. Therefore, develop- ing suitable lubricants has the potential to prolong the lifespan of prostheses or implants used in biomedical applications. The experiments collectively show that lubricants derived from palm oil could be used as efficient bio-lubricants in the future.

Surface Modified TiO2 Nanoparticles-an Effective Anti-wear and Anti-friction Additive for Lubricating Grease

The surface modified TiO_2 nanoparticles were prepared by using 12-hydroxystearic acid chemically modified on the TiO_2 surface. The average size of the TiO_2 particles is about 30 nm. The optimum ratio of tetrabutyl titanate to 12-hydroxystearic acid was 1/0.5. The bonding form between 12-hydroxystearic acid and TiO_2 nucleus was investigated by FTIR, DSC, TGA and XRD techniques. The lubricating grease containing the surface modified TiO_2 nanoparticles possesses excellent anti-wear and anti-friction properties. Compared with the grease without TiO_2, the PB value can be increased by 52% as the best performance of the grease containing surface modified TiO_2 nanoparticles, while the friction coefficient can be reduced by 33% with the addition of a small amount of TiO_2 nanoparticles, and meanwhile the wear scar diameter decreases by 25%.

Friction-reducing,Anti-wear and Self-repairing Properties of Sulfonated Graphene

The friction reducing properties of sulfonated graphene as a lubricating additive were investigated using a four-ball machine tester with high carbon chromium bearing steels GCr15（SAE52100） friction pairs. The microscopic morphology, elemental composition, and self-repairing properties were observed and analyzed by using scanning electronic microscopy（SEM）, X-ray diffraction（XRD） and digital microscopy. The relationships among sulfonated graphene ethanol solution concentration, friction coefficient, and abrasion loss were revealed. It was found that the optimal concentration of ethanol solution with the addition of sulfonated graphene was 0.15g/m L and the coefficient of friction was only 0.105 under certain condition. Then the stable chemical properties and good anti-corrosion properties of the metal-graphene layer were further confirmed using salt spray corrosion test. In summary, sulfonated graphene can be used as a new kind of self repairing additive, and it has excellent wear-resistant and self-repairing performances.

The Lubricating Effectiveness of S-Mo Extreme Pressure Additive and Its Anti-wear Mechanism

A kind of novel compound containing S and Mo elements was synthesized. Its chemical structure was characterized by elemental analysis, IR and 3MR. hs anti-wear property and the load-carrying capacity, as an extreme pressure （EP） additive of lubricating oil, were investigated using a four-bull tester. The experimentul results show that the additive exhibits a superior anti-wear property and a high load-carrying capacity . The presence of other additives does not interfere with the anti-wear prnperty of the extreme pressure additive. The influences of load and temperature on the propert） of the additive were examined. The possible mechanism uas investigated by means of sufface analysis of the tested steel ball specimen , using XPS. The lubricatian films formed on the rubbing surface are mainly composed of MoS2, MoO3 and MoO2.

Study on Friction Reducing and Anti-wear of CaCO_(3) Nanoparticles as Additives in Lubricating Oils

This paper has insepected the size and the structure of the calcium carbonate (CaCO3) particles by adopting X-ray diffraction and transmission electron microscope (TEM). The suitable surfactants have been selected and put into lubricating oil with nanometer CaCO3 particles. By testing some parameters, such as the maximum non-seizure load, the shape and diameter of wear scar, the friction factor, the nanometer CaCO3 particles’ properties of extreme pressure, anti-wear and friction reduction have been tested and analyzed. The properties of the nanometer CaCO3 particles’ tribology chemistry have been analyzed through X-ray photoelectron spectrum (XPS) test. Also the nanometer CaCO3 particles’ mechanism of anti-wear and friction reduction has been studied systematically. The research results show that, the lubricating oil with nanometer CaCO3 particles have good tribological properties.

Ashless Anti-Wear Additives for Motor Oils

Ashless anti-wear(AW) additives containing phosphorus can be used as partial or complete replacement of zinc dithiodialkylphosphate(ZDDP).In oils with low sulfated ash content(< 1.0%),this approach will allow a significant reduction of ash content and/or provide the formulator with more flexibility to use additional metallic detergents.Over the past 70 years or so,ZDDP has proven to be a very effective engine oil additive by helping to reduct oxidation,wear,and corrosion in service.In this paper,we will compare ZDDP-based lubricants with lubricants base on ashless,P-containing additive systems;we will describe the ashless chemistry investigated and discuss its contribution to wear performance in modern,low-SAPS(sulfated ash,phosphorus & sulfur) engine oils in various bench,rig and engine tests;we will also report on some work done to evaluate AW additive compatibility with modern three-way exhaust gas catalysts(TWC).

In-situ formation of nitrogen doped microporous carbon nanospheres derived from polystyrene as lubricant additives for anti-wear and friction reduction

This study presents a nitrogen-doped microporous carbon nanospheres(N@MCNs)prepared by a facile polymerization–carbonization process using low-cost styrene.The N element in situ introduces polystyrene(PS)nanospheres via emulsion polymerization of styrene with cyanuric chloride as crosslinking agent,and then carbonization obtains N@MCNs.The as-prepared carbon nanospheres possess the complete spherical structure and adjustable nitrogen amount by controlling the relative proportion of tetrachloromethane and cyanuric chloride.The friction performance of N@MCNs as lubricating oil additives was surveyed utilizing the friction experiment of ball-disc structure.The results showed that N@MCNs exhibit superb reduction performance of friction and wear.When the addition of N@MCNs was 0.06 wt%,the friction coefficient of PAO-10 decreased from 0.188 to 0.105,and the wear volume reduced by 94.4%.The width and depth of wear marks of N@MCNs decreased by 49.2% and 94.5%,respectively.The carrying capacity of load was rocketed from 100 to 400 N concurrently.Through the analysis of the lubrication mechanism,the result manifested that the prepared N@MCNs enter clearance of the friction pair,transform the sliding friction into the mixed friction of sliding and rolling,and repair the contact surface through the repair effect.Furthermore,the tribochemical reaction between nanoparticles and friction pairs forms a protective film containing nitride and metal oxides,which can avert direct contact with the matrix and improve the tribological properties.This experiment showed that nitrogen-doped polystyrene-based carbon nanospheres prepared by in-situ doping are the promising materials for wear resistance and reducing friction.This preparing method can be ulteriorly expanded to multi-element co-permeable materials.Nitrogen and boron co-doped carbon nanospheres(B,N@MCNs)were prepared by mixed carbonization of N-enriched PS and boric acid,and exhibited high load carrying capacity and good tribological properties.

内燃机活塞环材料及表面处理技术研究现状与发展趋势

活塞环是内燃机中重要的零部件之一,该部件的摩擦损耗占内燃机总摩擦损失的26%。因此,活塞环材料的选用及其表面处理研究对于优化提升内燃机性能、延长服役寿命具有重要意义。简单介绍并总结了内燃机活塞环常用材料及其发展趋势,详细综述了激光表面织构技术、表面涂层技术以及表面复合技术在内燃机活塞环减摩抗磨方面的研究和应用现状。其中,激光表面织构技术(LST)可起到接纳磨屑、保持油膜等作用,从而降低活塞环表面摩擦和磨损,但由于织构形貌和几何参数特征对摩擦学性能的影响较为复杂,仍需结合实际工况进一步研究并优化。以镀铬、热喷涂、气相沉积及激光熔覆为代表的涂层技术也常用于活塞环的表面强化处理,但涂层材料种类繁多,难以形成统一的行业标准进而规模应用。此外,通过合理复合多种表面处理技术,比如微弧氧化与电泳沉积复合、超声滚压与离子渗氮技术复合、磁控溅射和低温离子渗硫复合等,可实现优势互补、发挥协同作用,有效改善接触表面的摩擦性能,为活塞环的减摩增寿研究开拓了新的思路。最后对未来活塞环材料开发应用及其减摩抗磨方面的研究发展进行了展望。

超低剂量CI-415W-40柴油机油的研制及应用

基于我国社会经济和汽车工业的发展现状,未来一段时间内,市场中高、中、低档柴油机油将保持并存的局面,CI-4柴油机油仍是市场的主体,占有30%以上的份额。因此,为提高CI-4柴油机油性价比,优选以性能优异的金属清净剂、无灰分散剂和抗氧抗腐、抗磨剂等研制的复合剂,以8.3%的加剂量应用于适宜的基础油中,所调制的CI-415W-40柴油机油通过了Mack T-8E、Cat.1K、Cat.1P、程序ⅢF、Mack T-12、RFWT、EOAT和Cummins ISM等发动机台架试验,产品质量满足API CI-415W-40柴油机油标准的要求,并可实现6万km换油。

基于氢谱修饰指数的润滑油添加剂抗磨损性能的预测研究

润滑油添加剂对保障机械运行的稳定性和安全性、延长设备的使用寿命、节约能耗具有重要作用,由于通过实验获得数据费时费力,故用定量结构摩擦性能关系研究方法,来获取抗磨损性能数据成为一种简便而高效的方法.为研究酰肼类及磷酸类润滑油添加剂抗磨损性能与结构的关系,定义并建构了新的氢谱修饰指数^(0)H,并计算36个酰肼类及磷酸类分子的电性距离矢量,筛选了M_(2)、M_(3)、M_(21)和M_(59),将这5个结构描述符作为BP神经网络的输入变量,磨损体积量度V s作为神经网络输出变量,用5-3-1的神经网络结构,构建了神经网络法预测模型,模型相关系数0.944,磨损体积量度V s的预测值与文献实验值的平均相对误差为2.61%,优于文献方法结果.结果表明:酰肼类及磷酸类润滑油添加剂抗磨损性能与氢谱修饰指数有良好的非线性关系,影响抗磨损性能的主要因素是分子中原子特性、基团片段的—CH_(3)、—CH_(2)—、>CH—、—O、—N—和—P—等.该研究对指导合成新型抗磨损性能好的化合物分子有理论意义.

Enhancing the Tribological Performance of Conductive Grease Through the Modification of Polypyrrole with Ionic Liquids

This study prepared four types of ionic liquid-modified polypyrrole(IL-modified PPy)as conductive additives and investigated their tribological performance and conductivity in polytetrafluoroethylene lubricating grease.The results indicated that IL-modified PPy effectively enhanced the anti-wear performance and conductivity of the base grease.Among the additives,1-octyl-3-methylimidazolium tetrafluoroborate([OMIm][BF4])modified PPy showed superior performance compared to the other three additives,with the best effect observed at a mass fraction of 0.5%.X-ray photoelectron spectroscopy analysis revealed that IL-modified PPy forms a stable friction chemical film during the friction process,effectively enhancing the lubrication performance and conductivity of the base grease.This indicates broad potential applications in the field of conductive lubrication.

电机轴承用全氟聚醚润滑脂的研制与性能

研制了一种电机轴承用全氟聚醚润滑脂。通过对基础油,稠化剂和添加剂的考察,确定了电机轴承用全氟聚醚润滑脂由全氟聚丙醚基础油,聚四氟乙烯稠化剂,3%白炭黑,3%有机含锌盐抗磨极压剂,3%硫化异丁烯抗磨极压剂,2%纳米碳酸钙和3%有机硼酸酯抗磨极压剂组成。研制的电机轴承用全氟聚醚润滑脂的磨斑直径为0.41mm,烧结负荷P_(D)值达到7846N,最大无卡咬负荷值达到1961N,制备的全氟聚醚润滑脂与橡胶的相容性良好,达到了研制目标。(图4表9参考文献10)

专业篮球鞋鞋底综合性能要求与形态设计研究

随着全民运动的全面开展,高性能、专业化的篮球鞋也随之兴起并得到越来越多的关注。专业篮球鞋功能性的高低直接取决于其防滑、缓震、耐磨等性能。本文详细探讨了专业篮球鞋对鞋底性能的各方面要求与研究现状,提出基于综合性能提升的篮球鞋鞋底形态设计方案,如基于支撑性与耐久性的鞋底形态设计、基于防滑性的鞋底形态设计等,并探究了专业篮球鞋现代化、智能化的设计方法与技术,以促进各项鞋底设计方案的实现,丰富专业篮球鞋产品设计的创新方法。

热拌极薄抗滑磨耗层在高速公路抗滑性能提升中的应用

为研究热拌极薄抗滑磨耗层在高速公路养护中的应用,提升路面抗滑性能,论文结合实际工程,介绍了热拌极薄抗滑磨耗层工程特性,详细阐述了热拌极薄抗滑磨耗层原材料及配合比设计,重点对热拌极薄抗滑磨耗层施工技术要点进行研究。结果表明:公路养护中采取热拌极薄磨耗层技术进行处理,其路面抗滑性能得到有效提高,并节约养护成本。

橡胶减摩抗磨改性研究进展

橡胶因具有优异的理化性质及独特的力学性能而广泛应用于国防、航空航天、医用、交通、建筑及机械电子等领域,起到减震、缓冲和密封等作用.摩擦学性能是橡胶材料的重要指标之一,然而橡胶自身具有较高的摩擦系数,在一些应用领域,如活塞杆、阀轴(杆)密封、轮胎和水润滑轴承等,因黏连、摩擦生热、机械磨损及磨粒磨损等原因导致性能下降甚至失效.本文中首先综述了橡胶摩擦及磨损理论,随后从橡胶基体改性、橡胶表面处理以及表面织构化3个方面介绍了橡胶减摩抗磨改性方法的研究进展,并对其发展前景进行了展望.

风机叶片新型耐磨超疏水涂层的防覆冰性能研究

风力发电机叶片在服役过程中经常会受到覆冰影响,超疏水材料由于其特殊的湿润性,在防冰领域具有较大的应用潜力。基于此,以风力发电机叶片为基底,在其表面旋涂由环氧树脂(EP)、聚二甲基硅氧烷(PDMS)和改性的SiO2等配制的无氟悬浮液,固化后制得耐磨防冰的超疏水试样。采用扫描电镜、红外光谱仪和接触角测量仪分别对超疏水涂层的微观形貌、成分组成和疏水性能进行研究。结果表明:超疏水涂层的接触角为166.65°,滚动角为2.5°。相比于无涂层风机叶片,涂层在-10℃和-15℃延长结冰时间40%左右,并且涂层结冰后冰层的粘结强度明显小于风机叶片的。涂层在800目砂纸上磨损10 m后接触角为150.5°。制备的耐磨超疏水涂层具有超疏水效果和良好的防冰性能。

基于5-(2-羧基苯基)吡啶-3-甲酸配体的镍(Ⅱ)和锌(Ⅱ)配位聚合物的合成、晶体结构、催化及抗磨性质

采用水热方法,选用5-(2-羧基苯基)吡啶-3-甲酸配体(H_(2)cpna)与1,2-二(4-吡啶基)乙烷(dpea)或1,2-二(4-吡啶基)乙烯(dpey)分别与NiCl_(2)·6H_(2)O和ZnCl_(2)在160℃下反应,合成了2个三维配位聚合物{[Ni(μ3-cpna)(μ-dpea)_(0.5)]·H_(2)O}n (1)和{[Zn(μ_(3)-cpna)(μ-dpey)_(_(0.5))]·H_(2)O}_n (2),并对其结构、催化和摩擦性质进行了研究。研究表明,在室温条件下化合物2在Knoevenagel缩合反应中显示出较好的催化活性。同时,2在聚α-烯烃合成润滑剂中显示出有效的抗磨性能。

螺栓连接和拉铆连接在剪切循环荷载作用下的松动行为研究

拉铆连接凭借其优秀的防松性能,被应用于越来越多的工程领域。为研究国产新型拉铆钉在剪切循环荷载作用下的松动性能,以应用最为广泛的螺栓连接为对照,分别对规格为8 mm的4.8级普通螺栓、4.8级防松螺栓以及小规格拉铆钉进行剪切循环荷载下的松动试验研究,分析了三类连接在剪切循环荷载作用下的松动过程,研究了荷载幅值和频率对螺栓连接和拉铆连接松动行为的影响。结合微观测试手段分析其损伤形貌,进一步研究剪切循环荷载下螺栓和拉铆钉的防松原理及微动损伤机制。研究表明:在同种工况下拉铆连接的防松性能优于螺栓连接的防松性能;当荷载幅值增大或荷载频率减小时,螺栓连接和拉铆连接的松动程度增大;相较于螺栓,拉铆钉独特的圆弧结构牙型和铆接成型后牙型配合面的过盈配合机制,使其防松性能有明显提升;螺栓与拉铆钉的磨损机制主要是磨粒磨损和疲劳磨损。

石墨烯对聚脲脂高温流变和摩擦学性能的影响

目的保证轴承体系的安全性和可靠性,研究轴承润滑脂在不同工作温度下的摩擦学性能和流变学性能。方法用机械剥离法制备的石墨烯作为聚脲脂的润滑添加剂,通过四球摩擦试验机、旋转流变仪,研究石墨烯在不同工作温度下对聚脲润滑脂流变行为和摩擦学性能的影响,并通过三维轮廓仪、扫描电子显微镜和拉曼光谱仪对磨斑形貌和结构进行分析。结果添加石墨烯润滑添加剂使聚脲润滑脂的高温硬化现象明显改善,同时提高了聚脲润滑脂的结构稳定性和抗剪切能力。工作温度为75、150℃时,与空白聚脲润滑脂相比,含1.0%(质量分数)石墨烯的聚脲润滑脂润滑下的轴承钢摩擦副的摩擦系数和磨斑直径分别降低49%、20%和10%、20%。随着工作温度的升高,含石墨烯的聚脲润滑脂样品在钢滑动表面形成的沉积膜的结构有序化碳的含量稍有下降,但与空白聚脲润滑脂相比,石墨烯-聚脲润滑脂沉积膜的结构有序化碳含量高得多。结论结构有序化碳的形成对提高基础脂的减摩抗磨性能起至关重要的作用,石墨烯润滑添加剂还可以有效改善聚脲润滑脂的高温硬化性能、胶体稳定性以及稠化剂的结构稳定性。