Preparation and Tribological Behavior of Hydrophobic Lanthanum Borate Nanosheets in Rapeseed Oil

Oleic acid-capped lanthanum borate(abbreviated as OA/La BO_3·H_2O) nanosheets were prepared by the hydrothermal method. The microstructures of as-prepared OA/La BO_3·H_2O were characterized by means of SEM, TEM, EDS, FTIR and XRD, respectively. Moreover, the friction and wear properties of OA/La BO_3·H_2O as a lubricant additive in rapeseed oil were evaluated on a four-ball tribotester. The tribochemical characteristics of worn surfaces were investigated by SEM and XPS. The results showed that the hydrophobic OA/La BO_3·H_2O nanosheets exhibited their morphology with a diameter in the range of 100 nm to 300 nm and a thickness of about 25 nm, and displayed excellent dispersing stability in rapeseed oil. In the meantime, the rapeseed oil doped with OA/La BO_3·H_2O nanosheets markedly decreased the friction and wear of steel balls, and the optimal friction-reducing and antiwear ability of rapeseed oil was obtained at an OA/La BO_3·H_2O content of 1.0%. The outstanding tribological performance of OA/La BO_3·H_2O in rapeseed oil was attributed to the formation of a composite boundary lubrication film mainly composed of lubricious tribochemical species of B_2O_3, La_2O_3 and Fe_2O_3, and deposits of OA/La BO_3·H_2O nanosheets as well as the adsorbates of rapeseed oil on rubbed surfaces.     

Synthesis of Two Novel Additives and Study of Their Tribological Properties in Rapeseed Oil

Two novel ashless additives - benzothiazole derivatives containing boron and chlorine, OBC and BBC, were synthesized. The tribological performances of OBC and BBC at different mass ratios as additives in rapeseed oil （RO） were examined on a four-ball machine. The worn surfaces of the lower steel balls lubricated by oil samples were analyzed by means of scanning electron microscopy （SEM）. The test results showed that OBC and BBC had good solubility in the base oil, and could effectively increase the load-carrying capacity of the base oil. The maximum non-seizure load of oil sample containing 1.5 m% BBC was 1117 N, which was 2.3 times as much as that of the base oil. Both OBC and BBC could improve the anti-wear and corrosion inhibiting performance and thermal stability of the base oil, whose initial decomposition temperatures was above 350 ~C. However, OBC and BBC at different concentrations could increase the friction coefficient of the base oil. The SEM morphology of steel balls lubricated by oil samples containing 1.5 m% additives seemed to be more uniform and smoother than that of the base oil, and the scars formed were very shallow.     

滚滑接触下4129航天润滑油的摩擦特性

The friction coefficients between the surfaces of a ball and a disc lubricated by a space lubricating oil No.4129 were measured at various operating conditions on a ball-disc friction test rig. Friction characteristic curves were obtained under sliding and rolling movements at point contact. A new model for calculation of the friction coefficient was presented. The results show that the bigger the load is, the larger the friction coefficient becomes. The rolling speed ranging from 1 m/s to10 m/s has an important effect on the friction coefficient. The friction coefficient increases with the increase in sliding speed and the decrease in rolling speed. The linear variation region of the friction coefficient versus the sliding speed at high rolling speed is wider than that at low rolling speed. The model for calculation of the friction coefficient is accurate for engineering use.     

含惰性和活性功能元素CVT传动液的摩擦润滑特性研究

The lubricating characteristics of CVTF （continuously variable transmission fluid） mixed with a multi-functionalcomplex additive were studied. The said complex additive contained an organic borate ester and a new type of friction improvercomprising phosphorus element and poly-methylmethacrylate （PMMA）, and a viscosity index improver. The viscosity-pressure characteristics were evaluated by a high-pressure quartz viscometer, and the anti-wear property was investigatedby a four-ball friction tester. The mechanism of lubrication by the CVTF was studied using X-ray photoelectron spectroscopy（XPS）. The results showed that CVTF T10, which contained a multi-functional complex additive, exhibited excellentproperties, featuring greater solidification pressure and pressure-viscosity coefficient, improved oil film strength, and lowwear value. These attributes meet the special CVTF requirements for “high friction and low wear” that make it possible toprovide both traction and lubrication. The lubricating mechanism was varied using different functional elements, such asinert and active elements. Sulfur and phosphorus are active extreme pressure elements that can react on the metal frictionsurface and produce an extreme pressure lubrication film. Boron is an inert functional element and does not react upon themetal surface; boron is only adsorbed onto the metal surface to act as a lubricant for adsorption film and fillers.     

Friction and Wear Behaviors of Nano-Silicates in Water

Nano-metric magnesium silicate and zinc silicate with particle size of about 50—70nm were prepared in water by the method of chemical deposition. The antiwear and friction reducing abilities of the nano-silicates,as well as their composites with oleic acid tri-ethanolamine(OATEA) ,were evaluated on a four-ball friction tester. The topographies and tribochemical features of the worn surfaces were analyzed by scanning electron microscope(SEM) and X-ray photoelectron spectroscope(XPS) . Results show that nano-...     

Study on Tribological Behaviors of Boron-Nitrogen Modified Fatty Acid as Water-Based Lube Additives

A new type of boron - nitrogen modified fatty acid as water base lube additive was prepared and the chemical structure characterized by infrared spectrum. The tribological properties of the additive in water were evaluated by friction testers. The morphographies and tribochemical species of the worn surfaces were analyzed by means of X - ray Photoelectron Spectroscope （XPS）.The results showed that the additive is excellent in increasing load - carrying capacity, anti - wear and friction - reducing abilities of water. The lubrication mechanism is inferred that a high strength adsorption film and a tribochemical reaction film are formed on the rubbing surfaces due to the carder effect of the long chain fatty acid molecules, high reaction activities of nitrogen, electron - deficient orbit of boron and their synergisms.     

改性纳米氧化锌在基础油中的润滑性能研究

ZnO nanoparticles with an average size of 125 nm were prepared via homogeneous precipitation method and were characterized by SEM.The products were surface-modified by the surfactant SDS.Surface-modified nano particles were added at a mass ratio of 1.0%,2.0%,3.0%,and 4.0%,respectively,in base oil and their friction and wear behaviors were evaluated on a MRS-10D type four-ball wear tester.After four-ball wear tests,the morphology of the rubbing surfaces was evaluated with metallographic microscope.It was revealed that the modified nano ZnO had excellent behavior for improving anti-wear property and friction coefficient,which could greatly reduce the friction of machine parts.     

Tribological Properties of Functionalized Ionic Liquids Containing Ester-group as Lubricants for Steel-Steel System

A series of functionalized ionic liquids (ILs) containing ester-group were synthesized and their tribological properties as lubricants for steel-steel contact were studied and compared with a non-functionalized ionic liquid and perfluoropolyethers (PFPE). The morphology and chemical composition of the worn scars were analyzed by scanning electron microscopy and X-ray photoelectron spectroscopy, respectively, and the possible lubrication mechanism of ILs was discussed. As a result, all ILs demonstrated a better lubricity and a much higher load-carrying capacity than PFPE used as lubricants for the steel-steel tribomates system. The functionalized ILs with ester-group showed slightly worse friction reducing ability than their nonfunctionalized counterparts at relatively lower loads owing to their higher viscosity, but then exhibited better antiwear ability because the ester group they contained had not only physical but also strong chemical reactions with the freshly exposed steel surface and formed chemical adsorption boundary films on the worn surface during friction process. Under high loads, some tribochemical reactions took place between the active elements, such as fluorine which were released from the ILs, and fresh metal surfaces of rubbing pairs to form the admixture reaction films, which were mainly composed of ferric fluoride mixed with ferric oxide, leading to lower friction coefficients and good wear resistance.     

钨膜的制备及其在边界润滑情况下的摩擦学性能研究

Tungsten film （W film） is deposited by using the ion beam assisted deposition （IBAD） on the 316L substrate surfacein this experiment. The micro structure and nano-hardness of the film are investigated by scanning electron microscopy（SEM） and nano-indentation tester. The tribological behavior of W film under lubrication by oil with ZDDP and MoDTCis evaluated by a SRV test machine. The tribo-film formed on the worn surfaces is investigated by X-ray photoelectronspectroscopy （XPS） to find out the tribological mechanisms between the W film and the two additional additives. The resultshows that the W film lubricated by ZDDP and MoDTC-blended base oil has synergistic effects on the friction reductionproperty, while the anti-wear property is mainly caused by the hard surface of W film.     

Tribological Behaviors of S,B-Containing Morpholine Derivatives as Additives in Rapeseed Oil

Two novel ashless and non-phosphorus S, B-containing morpholine derivatives, MBOC and MBOD, were prepared and their tribological behaviors in rapeseed oil （RSO） were evaluated using a four-ball tester. Thermal degradation tests were conducted to identify their thermal stabilities using a thermo-gravimetric analyzer. The worn surfaces of the steel balls were investigated by scanning electron microscopy （SEM）. The results indicated that the additives possessed high thermal stabilities and good load-carrying capacities. Moreover, they both had good anti-wear and friction reducing property at a relatively high concentration （1.5 m%） and under all test loads. The results of XPS analyses illustrated that the prepared compounds as additives in RSO could form a protective film containing inorganic sulfide, sulfate, oxidized compounds and organic nitrogen-containing compounds on the metal surface during the sliding process.     

硫化菜籽油润滑添加剂对钢-镁摩擦副摩擦学性能的影响

在菜籽油（RO）分子中引入硫,合成了一种新型可生物降解润滑添加剂（SRO）,通过SRV摩擦磨损试验机考察了以菜籽油为基础油,以SRO为添加剂时对GCr15钢- AZ91D镁合金摩擦副摩擦学性能的影响,用扫描电子显微镜观察分析镁块磨斑表面的形貌,同时通过对镁合金磨痕进行X射线光电子能谱分析。结果表明：以菜籽油为基础油时,硫化菜籽油润滑添加剂对钢-镁摩擦副具有优良的抗磨减摩性能;其润滑作用机理是由于长链菜籽油分子的载体作用、硫的高反应活性以及二者的协同作用与摩擦金属表面形成了一层高强度的吸附膜和（或）摩擦化学反应膜。     

含氮、氧改性菜籽油润滑添加剂对钢-钢摩擦副和钢-铝摩擦副摩擦学性能的影响

对菜籽油进行化学改性制备了一类氮氧型改性菜籽油添加剂（NOR），并利用红外光谱对其主要官能团进行鉴定。分别通过四球和SRV摩擦磨损试验机考察了以菜籽油为基础油，以NOR为添加剂时对钢-钢摩擦副和钢-铝摩擦副抗磨减摩性能的影响，用扫描电子显微镜观察分析钢球磨斑表面的形貌，同时通过对铝合金磨痕进行X射线光电子能谱分析，探讨了氮氧型改性菜籽油润滑添加剂的抗磨减摩机理。结果表明：以氮氧型改性菜籽油为添加剂，以菜籽油为基础油时，钢-钢摩擦副和钢-铝摩擦副均表现出良好的抗磨减摩作用，其润滑作用机理是由于长链菜籽油分子的载体作用、氮的高反应活性以及二者的协同作用在金属摩擦表面形成了含氮、氧及碳等元素的表面保护膜。     

硼化蓖麻油润滑添加剂对钢-钢和钢-镁摩擦副摩擦学性能的影响

在蓖麻油(CO)分子中引入硼,制备了一种新型环境友好润滑添加剂(BCO),并利用红外光谱对其主要官能团进行表征。通过四球和SRV摩擦磨损试验机考察了以菜籽油为基础油、以BCO为添加剂时对钢-钢摩擦副和钢-镁摩擦副抗磨减摩性能的影响;用扫描电子显微镜观察分析钢球磨斑表面的形貌,同时通过对镁合金磨痕进行X射线光电子能谱分析,探讨了BCO添加剂的抗磨减摩机理。结果表明,BCO添加剂在菜籽油中具有优良的极压抗磨和减摩性能;其润滑作用机理是由于长链蓖麻油分子的载体作用、硼的缺电子性以及二者的协同作用与摩擦金属表面形成了一层高强度的吸附膜和/或摩擦化学反应膜。     

羟基化改性菜籽油润滑添加剂对镁合金摩擦学性能的影响

在菜籽油(RO)分子中引入羟基,合成了一种新型的环境友好型润滑添加剂(HORO),并利用红外光谱对其主要官能团进行了鉴定。通过SRV摩擦磨损试验机考察了以菜籽油为基础油、以HORO为添加剂时对钢-镁摩擦副抗磨减摩性能的影响,同时通过X射线光电子能谱对镁合金磨斑表面进行分析,探讨了羟基化改性菜籽油润滑添加剂的抗磨减摩机理,并对生物降解性能进行了评定。结果表明:羟基化改性菜籽油润滑添加剂对钢—镁摩擦副具有优良的极压抗磨和减摩性能,2%的该种添加剂能使镁合金磨损体积从7.8 mm3降低到2 mm3,摩擦系数则从0.054降低到0.043;其润滑作用机理是由于长链菜籽油分子在镁合金摩擦表面进行吸附或发生摩擦化学反应形成了摩擦聚酯膜与镁的氧化膜共同组成的起抗磨作用的润滑膜;生物降解试验表明羟基化改性菜籽油具有优异的生物降解性能。由此推断,研制的羟基化改性菜籽油是一种性能优异的环境友好镁合金润滑添加剂。     

航空润滑油变质与镁合金腐蚀模拟实验

通过对航空发动机润滑油系统镁合金部件的腐蚀特征分析 ,认为航空润滑油中的微生物是引起镁合金部件腐蚀的主要原因 ;采用浸泡挂片模拟实验进行研究 ,发现硫酸盐还原菌可以引起镁合金腐蚀 ,且腐蚀特点为点蚀。结果表明 ,硫酸盐还原菌的腐蚀特点与航空发动机润滑油系统镁合金部件的腐蚀特征相吻合。     

磷酸三丁酯和磷酸三苯酯作为菜籽油添加剂的摩擦学特性

利用四球机考察了磷酸三丁酯(TBP)和磷酸三苯酯(TPP)作为菜籽油添加剂在不同条件下的摩擦学性能，研究了承载能力和抗磨性与添加剂含量之间的关系，探讨了TBP和TPP在不同负荷下的抗磨作用机理。结果表明，TBP和TPP能明显改善菜籽油的抗磨性，有效提高菜籽油承载能力；相同试验条件下，特别是高负荷的情况，TPP的抗磨性能优于TBP；TBP和TPP的质量分数分别为1．5％和1．0％时，菜籽油的抗磨性最好；其作用机理是由于长链植物油分子的载体作用、添加剂中磷的高反应活性及其和植物油分子的协同作用，低负荷工况下在摩擦金属表面形成一层高强度的吸附膜；高负荷工况下形成摩擦化学反应膜。     

硼氮化大豆油对菜籽油生物降解性和润滑性的影响

通过对大豆油进行化学改性，合成了2种硼氮化添加剂BNS-1和BNS-2，研究了BNS-1和BNS-2对菜籽油生物降解性和润滑性的影响；通过扫描电镜和能谱仪分析了磨损表面的形貌及元素组成。结果表明：BNS-1和BNS-2可提高菜籽油的极压性能，具有较好的抗磨减摩性能，BNS-2的减摩效果优于BNS-1，BNS-1的抗磨效果优于BNS-2；BNS-1和BNS-2对菜籽油的生物降解性影响较小。硼氮化添加剂的润滑机理是硼元素的缺电子性，氮的高反应活性，在摩擦高温条件下，硼与氮发生化学反应，形成化学反应膜，从而提高了基础油摩擦学性能。础油摩擦学性能。     

硫化蓖麻油润滑添加剂在菜籽油基础油中的摩擦学性能

在蓖麻油分子中引入硫,合成了一种新型环境友好润滑添加剂（SCO）,并利用红外光谱对其主要官能团进行了表征。通过四球试验机考察了SCO在菜籽油中的抗磨性能与极压性能,用X射线光电子能谱仪对其磨痕表面元素进行分析,探讨该类添加剂的极压抗磨作用机理。结果表明,硫化蓖麻油润滑添加剂在菜籽油中具有优良的极压抗磨和减摩性能,其润滑作用机理是由于长链蓖麻油分子的载体作用、硫的高反应活性以及二者的协同作用与摩擦金属表面形成了一层高强度的吸附膜和（或）摩擦化学反应膜。     

油酸甲酯型含氮硼酸酯的合成及其抗磨减摩特性

通过环氧化处理、环氧基非对称亲核开环反应和酯化反应在油酸分子双键位置引入含氮硼酸基团,制备了一种油酸甲酯型含氮硼酸酯类化合物(BN),并采用傅里叶红外光谱仪表征了合成产物的化学结构。将BN添加于液体石蜡和菜籽油2种不同基础油中,采用四球摩擦试验机测定了其抗磨减摩特性。结果表明,油酸甲酯经硼氮化改性后,极压抗磨性能明显提高。与添加油酸甲酯的液体石蜡相比,添加BN的液体石蜡的PB值从470 N增加到696 N,提高4840%;PD值从1148 N增加到1569 N,提高3667%;磨斑直径从055 mm减小到044 mm,减少20%。与添加油酸甲酯的菜籽油相比,添加BN的菜籽油的PB值从539 N增加到921 N,提高7087%;PD值从1236 N增加到2452 N,提高9838%;磨斑直径从056 mm减小到044 mm,减少2143%。合成的硼氮化改性油酸甲酯可以作为菜籽油和液体石蜡等基础油优良的极压抗磨添加剂,且菜籽油对其感受性要好于液体石蜡。     

含硼杂环抗磨添加剂的合成及其摩擦学性能

 从分子设计的观点出发，合成了一种新型含硼杂环抗磨添加剂SONB，采用四球摩擦磨损试验机评价了其摩擦学性能。结果表明，在菜籽油(RSO)中加入添加剂SONB后，承载能力有较大提高，磨斑直径明显减小，摩擦系数明显降低。从磨损表面SEM/EDS、XPS分析结果可以推断，该添加剂在摩擦过程中发生了化学分解反应，S元素在钢球的表面形成了一层含Fe₂(SO₄)₃和FeS₂ 的反应膜，N、B元素则以吸附膜的形式存在于摩擦表面， 两种膜的协同作用提高了菜籽油的减摩抗磨性能及承载能力。