含超细颗粒固液二相流对PSZ陶瓷与钢摩擦磨损特性的影响

在往复式摩擦磨损试验机上研究了含超细颗粒固液二相流对部分稳定二氧化锆（ＰＳＺ）陶瓷与ＧＣｒ１５钢滑劝副的摩擦磨损性能的影响。选择９０＾＃机械油和ＱＣ３０汽机油为基础油,分别加入五种超细固体颗粒,配制出不同浓度的２０种油样,分别在１６０１７０和１００℃温度下进行试验。结果表明：超细固体颗粒添加剂的用量、试验温度和基础油都影响陶与钢滑动副的摩擦磨损性能。对超细颗粒添加剂的润滑机理进行了初步探讨。     

Effect of lubricants on the friction and wear of Al2O3 against gray cast iron

The tribological behavior of ceramic Al₂O₃ coupled with gray cast iron (PHT) with different lubricants was investigated using a ring-on-block wear tester. In the wear test, air, distilled water, emulsion and oil were used as lubricants respectively in order to check the lubricating effectiveness of lubricants and the friction mechanism of solid graphite in the cast iron. Wear testing of 0.8% C steel (T8) sliding with Al₂O₃ was also carried out to compare with the test using gray cast iron. From these data the tribological behavior of graphite in the iron can be evaluated. The results show that the friction and wear of tested couples are decreased using different lubricants in the following order: air, distilled water, emulsion and oil. When lubricating with air and water, graphite in the iron as solid lubricant can decrease the friction and wear of the couples. However, when lubricating with emulsion and oil, graphite does not show the advantage of decreasing friction and wear.     

The Lubricity of Gasoline

A study has been made of the lubricating properties of gasoline fuel. A conventional HFRR diesel fuel lubricity tester has been modified to measure gasoline wear. Using this test equipment, a number of features of gasoline lubricity have been investigated, including the comparative lubricating behavior of gasoline, the influence of detergent additives and oxygenates on wear and the wear behavior of a series of refinery streams employed in gasoline blending.

The lubricity of a range of pure organic chemicals known to be present in gasoline has also been studied. From these measurements it has been shown that, except for components such as dienes and diaromatics, the HFRR lubricating properties of most gasoline hydrocarbon constituents are broadly independent of chemical structure bur depend significantly on viscosity. Using these measurements, predictive wear equations based on gasoline group analysis have been developed.

Because it has been found that viscosity plays a role in determining the wear properties of gasoline, the elastohydrodynamic (EHD) film-forming and friction properties of gasoline have been measured and compared to those of diesel fuels. This shows that the combination of gasoline's very low viscosity and low pressure-viscosity coefficient results in very thin EHD film thickness generation and also very low friction in full-film EHD conditions.     

基于单片机的双积分球组织光学特性参数测量系统

研制了基于 5 1单片机和相敏检测模块 CD5 0 5 R2的双积分球组织光学特性参数测量系统。阐明了该系统的工作原理、硬件组成和软件设计 ;通过对标准样品 (Intralipid,Evans Blue)光学特性参数 (6 32 .8nm )的测试 ,证明了该系统具有精度高、操作便捷、性价比高的优点。     

The Influence of Moving Dent on Point EHL Contacts

A transient analysis for a dent passing through the conjunction of a point EHL contact was developed and solved numerically by using the multigrid method. Results show that the presence of sliding produces a noticeable pressure ridge and thus, a surface indentation at either leading side of the dent if the dent moves slower than the opposite surface, or at the trailing side if the dent moves faster than the opposite surface. The pressure ridge and surface indentation extend their lengths forward or backward from the dent in the sliding direction at a rate approximately half the sliding speed. The pressure fluctuation associated with the dent increases with increasing slide-to-roll ratio and dent depth, and decreases with increasing dent width in both x- and y-directions. The agreement between numerical simulation and experimental results obtained by Wedeven and Cusano (I) is remarkably close.     

光纤连接器插芯微内孔研磨实验装置设计

根据光纤连接器陶瓷插芯微内孔研磨的要求,分析和探讨了研磨加工的机理和工艺特点,设计了相应的研磨实验装置.实验证明:该装置设计合理、运行平稳、参数调整方便,完全满足对陶瓷插芯微内孔加工实验研究的要求,也可以作为工业生产装备使用.     

一种二甲醚专用润滑性改进剂的性能研究

采用四球机和高频往复试验机研究了一种二甲醚(DME)专用润滑性改进剂在不同基础试验液体中的润滑特性,考察了其与醚的互溶性能及对金属的腐蚀性能,并与其它润滑性改进剂进行了对比,从而为DME发动机选择合适的燃料润滑改进剂提供了依据。结果表明:该DME专用润滑性改进剂添加量少,润滑效果显著,与DME相容性好,没有腐蚀性。     

Tribological properties of linear phosphazene oligomers as lubricants

The friction and wear behavior of a steel-on-steel contact lubricated by two novel synthetic linear phosphazene oligomers with different side branches and by perfluoropolyethers (PFPE) was comparatively investigated on an oscillating friction and wear tester. The thermal stability of the lubricants was investigated by means of thermogravimetric analysis. The worn surfaces were analyzed by means of scanning electron microscopy, energy-dispersive spectrometry, and X-ray photoelectron spectroscopy. It was found that the two synthetic linear phosphazene oligomers were more effective than PFPE in increasing the wear-resistance of the steel-on-steel frictional pair. The phosphazene oligomer having aromatic rings had better friction-reducing ability and higher thermal stability, and that having fluoropolyether gave higher load-carrying capacity. Tribochemical reaction was involved in the sliding of steel against steel under the lubrication of the lubricants, with the generation of a protective layer composed of inorganic fluoride FeF₂ and organic compounds consisting of C, F, O, N and P. The protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic compounds played an important role in improving the friction and wear behavior of the steel-on-steel system.     

The role of fragility in EHL entrapment

Experimental measurements of time dependent film thickness in entrapped liquids, measurements of viscosity under pressure, and simulations using realistic pressure–viscosity models contribute to improved understanding of the mechanisms of entrapment formation and persistence. The ambient viscosity and pressure–viscosity coefficient affect entrapment only as much as they are predictors of behavior at much higher pressure. Fragile liquids, such as lubricating oils, experience rapid increase in sensitivity of dynamic properties to temperature and pressure as the glass transition is approached. The fragility property of lubricants appears to be of overwhelming importance to entrapment which experimental evidence indicates will reduce starting friction.     

基于压电阻抗的设备结构健康智能诊断

利用压电陶瓷(PZT)智能材料作为驱动源产生的波动信号，结合人工神经网络控制方法对设备及结构进行健康智能诊断，并通过实验对结构缺陷进行了健康智能诊断，证实了这种方法的可靠性。     

一种抗燃液压液的研究

由乙二醇，去离子水，稠化剂，自制水溶性润滑剂，防锈剂和抗泡剂等组成的抗燃液压液，用作浇铸机的铝铸件加工，满足了使用要求。     

大规模定制下的眼镜设计方法与实现过程

简单介绍了大规模定制设计的内容，提出了Internet环境下的大规模定制设计模式；探讨了以B／S模式构架面向用户的眼镜远程定制平台，以参数化和尺寸驱动等方法来构造眼镜产品的定制模型，开发出基于Internet的眼镜大规模定制设计系统。并以眼镜设计和试镜为例．演示了所提出的方法和开发系统的实际应用。     

润滑油温度对发动机的影响

润滑油温度过低、过高直接影响发动机的机械效率、功率和使用寿命。本文主要分析了润滑油工作温度异常对发动机各种工况下的影响因素、损伤机理、使用技术及对策。     

摩擦系数对齿轮接触疲劳寿命的影响

通过四球试验机测试了两种极压抗磨添加剂的摩擦系以及用该添加剂分别配制的两种工业齿轮油的摩擦系数，并用动静摩擦系精密测定仪测试了两种润滑油的动静摩擦系数。同时球柱型接触疲劳试验机的实验结果证明，低摩擦系数的摩擦副疲劳寿命长，说明摩擦系数是影响疲劳寿命的一个重要因素。     

Tribological performance of a DLC coating in combination with water-based lubricants

The tribological behaviour in water-based environments has been studied for a tungsten carbide-doped DLC coating (WC/C) deposited by physical vapour deposition (PVD) on bearing steel. Several tribological test equipments have been used to characterise the wear rate, coefficient of friction and resistance to seizure of the coated system, in comparison with uncoated bearing steel surfaces. It was observed that the wear was decreased and the coefficient of friction reduced in pin-on-disc measurements for poor lubricants. Further, the resistance to seizure in the four-ball method was improved by a factor of approximately three. Results from Reichert measurements showed a decreased wear rate and also a very pronounced running-in behaviour of the coating for some water-based lubricants. It has been shown that the performance of tribological systems with water-based lubricants can be significantly improved with this type of DLC coating.     

Synergistic and antagonistic effects on oxidation stability of antioxidants in a synthetic ester based oil

Synergistic and antagonistic effects have been observed with the four sulfur-, phosphorus- and heavy metal-free antioxidants, hindered bis-phenol, octylated diphenylamine, octylated phenyl-alpha-naphthylamine and tolutriazole derivative, on the oxidation stability, thermal and physicochemical properties of dioctyl sebacate oil. The oxidation stability was evaluated using a rotary bomb oxidation tester. The results from isothermal and catalytic RBOT oxidation tests suggested that ODPA has an antagonistic effect on the OIT. The combination of HP:OPANA:TZ exhibited the highest and most synergistic antioxidant activity. Furthermore, synergism was observed in terms of both oxidation and thermal stabilities through thermogravimetric analysis (TGA).     

纳米坡缕石的分散工艺对润滑油摩擦性能的影响

研究了纳米坡缕石的分散工艺对润滑油摩擦性能的影响。结果表明,三种分散工艺均可将纳米坡缕石均匀分散到基础油中。在室温下放置24h后,方案二和方案三出现少量沉淀,方案一无沉淀出现。在摩擦试验条件下,三种方案对应的平均摩擦系数分别为0.06518、0.06688、0.07011。     

Improved anti-shudder performance of ATFs—Influence of a new friction modifier and surface chemistry

Among OEM strategies for increasing fuel economy and reducing emissions, driveline performance optimisation by using automatic transmissions is particularly important. Technology advances in automatic transmission designs are leading to continued growth of the number of vehicles with automatic transmissions. In fact, over the next five years, it is expected that the market share for automatic transmissions will increase to greater than 60%, with Europe being the largest region for this growth.The performance of automatic transmissions, especially anti-shudder performance, is highly dependent on friction modifiers and other additives in automatic transmission fluids (ATFs). These additives, in a manner similar to engine oil additives, are expected to interact with the steel and clutch material surfaces to form surface films that provide the desired performance. Hence, understanding the tribochemical processes in this automatic transmission system is a very important step towards performance optimisation. While the tribochemistry of engine oil additives and the nature of tribofilms on metallic surfaces are relatively well researched, the tribochemistry of ATFs still remains largely unclear. One reason for this is the level of complexity in analysing the friction materials of automatic transmission systems. Separating lubricant-derived species from the composite clutch friction materials is not trivial.This paper presents a comprehensive look at the tribochemistry of a new friction modifier in ATF systems and assesses the nature of the tribofilms formed on steel and composite friction materials in a variable speed friction test (VSFT) apparatus, which was used to simulate the clutch friction process. The tribofilm evolution is correlated with the tribological response as ageing occurs. Functional groups from the friction modifiers were found on the friction couple surfaces after the test and the mode of their action is discussed. These groups were proposed to form a layer of tribofilm on the top surface after rubbing. The correlation between observed tribochemistry processes and the tribological performance are discussed in detail.