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research on Friction Properties of Mineral lubricants in Thin-Film-Lubricating Regime

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China Petroleum Processing & Petrochemical Technology 2014年第1期16卷 90-95页

作者： Zhang Jie Guan Tingting Piao Jicheng lubricants R&D Institute PetroChina

On the basis of thin film lubrication theory, the influence of fluid film(disordered film), ordered film and adsorbed film on tribological behavior of lubricating oil in thin-film lubrication(TFL) regime was studied. The μ-L(friction coefficient versus load) curves of different oil viscosity and additive dosage were obtained by a high frequency reciprocating test rig and the adsorption capacity of additive on steel surface were measured by QCM-D. Based on the Stribeck curve and thin film lubrication theory model, some conclusions can be drawn up, namely:(1) The μ-L curves and the parameters of L0 and μ0, obtained from the high frequency reciprocating test rig with ball-disc contact, can be used to study tribological behaviors of lubricating oil under TFL conditions.(2) In comparison with the high viscosity base fluid, the lower one can enter into TFL regime under lower load and keeps a lower friction coefficient in TFL regime.(3) The polar molecules in additive formulation produce ordered adsorbed layer on steel surface to reduce friction coefficient. And in TFL regime, the molecule's polarity, layer thickness and saturation degree on steel surface probably can influence lubricant's tribological behaviors between the moving interfaces. Moreover, the further study would be focused on the competitive adsorption of different additives, the formation of dual- and/or tri-molecular adsorption layers, and other aspects.

关键词： thin film lubrication(TFL) adsorption film quartz crystal microbalance with dissipation monitoring(QCM-D) Stribeck curve mineral lubricants

Effect of dicarboxylic acid esters on the lubricity of aviation kerosene for use in CI engines

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Friction 2013年第3期1卷 271-278页

作者： G.ANASTOPOULOS S.KALLIGEROS P.SCHINAS F.ZANNIKOS National Technical University of Athens School of Chemical EngineeringLaboratory of Fuels Technology and LubricantsIroon Polytechniou 9Athens 15780Greece Hellenic Naval Academy Laboratory of Fuels&Lubricants TechnologyEnd of Hatzikiriakou AvenuePiraeus 18539Greece

To reduce their fuel related logistic burden,North Atlantic Treaty Organization(NATO)Armed Forces are advancing the use of a single fuel for both aircraft and ground *** this end,F-34(the commercial equivalent is Jet A-1)is replacing distillate diesel fuel in many ***,tests conducted with this kerosene type on high frequency reciprocating rig showed that this type of fuel causes unacceptable *** excessive wear is caused by the poor lubricity of aviation *** order to make this type of fuel compatible with direct injection compression engines,seven di-carboxylic acid esters have tested to improve the lubricity of *** results showed that all esters tested in this series of experiments seem to be suitable for increasing the kerosene lubricity to a satisfactory level.

关键词： lubricity aviation kerosene F-34 Jet A-1 compression ignition(CI)engines dicarboxylic acid esters

Analysis of surface and sub-surface of cold-rolled Al plate lubricated with water-or oil-based lubricants

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Science China(Technological Sciences) 2017年第9期60卷 1407-1414页

作者： TANG XiWen ZHANG ChenHui WANG Yan YANG Ye HU Juan State Key laboratory of Tribology Tsinghua University Beijing 100084 China Shenzhen Key laboratory of Micro-nano Manufacturing Research Institute of Tsinghua University in Shenzhen Shenzhen 518057 China Nanjing Golden Chemical Co. Ltd Nanjing 210019 China

For environmental protection, energy conservation, and other reasons, water-based lubricants are increasingly chosen to replace oil lubricants. Water-based lubricants are divided into emulsified and solution types. Solution type water-based lubricants have attracted significant attention for the good stability, easy biodegradability, and safety for workers. However, some problems exist with current solution type water-based lubricants, such as poor lubricity and corrosion resistance. During the cold-rolling process, A1 plate rolled using oil-based lubricant lubrication shows metallic luster, but that rolled using water-based lubricant shows corrosion spots, black strips, and no metallic luster. Therefore, this study mainly analyzed the reasons for the darkness of A1 plate cold-rolled with water solution lubricants. The differences in plate surfaces lubricated by water solution and oil were investigated by scanning electron microscopy, auger electron spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The analysis results showed that the surface of the oil-lubricated sample is smooth, the oxygen content is low, and the oxide layer is thin, while the surface of the water solution-lubricated sample is rough, the oxygen content is high, the chemical composition is more complex, and the oxide layer is not uniform and thick.

关键词： water-based lubricant oil-based lubricant cold-rolled al surface oxidation

Wax deposition modeling in oil-water stratified pipe flow

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Petroleum Science 2023年第1期20卷 526-539页

作者： Hui-Shu Liu Ji-Miao Duan Jiang Li Jian Wang Hao Yan Ke-Yu Lin Ke-Cheng Gu Chang-Jun Li Petroleum Engineering School Southwest Petroleum UniversityChengdu610500China Petroleum Oil and Lubricants DepartmentArmy Logistics AcademyChongqing401311China

Wax deposition in oil-water stratified flow is commonly encountered onshore and offshore oil production pipe systems,and typically reduces transportation capacity of *** accurate predicted model of wax deposition has becomes an indispensable approach to design effective remediation ***,a reliable mechanistic model for wax deposition prediction in oil-water two-phase stratified pipe flow is lacking to validate the deposition *** this work,a three-dimensional(axial,radial,and angular)robust wax deposit model for oil-water stratified circular pipe flow was *** model of formation of a gel deposit based on the first principles of rheology was developed,associated with the results obtained from hydrodynamics and heat/mass transfer *** predictions for wax deposition are found to compare satisfactorily with experimental data with two different oils for single phase and four different water cuts for oil-water stratified pipe *** can be seen from the wax gelation mechanism that an increase in water cut can help to reduce the wall/oil-deposit interface shear stress,thereby leading to an increase in the degree of gelation as well as the deposit ***,a local deposit analysis in the circumferential direction was conducted,for water cut 75%and total flow rate 5 m3/h,which provided insights to understand that the thickness on pipe wall was roughly uniformly distributed locates near the top of the pipe and the nearer the position gets close to two points,where the oil-water interface contacts the inner wall,the deposition thickness quickly dropped to *** was attributed to the fact that a roughly uniformly thickness far away from the oil-water interface contact the inner wall resulted in the slowly changes temperature along the circumferential pipe wall wetted by oil.

关键词： Wax deposition Oil-water flow Stratified flow Heat and mass transfer

Identification of Heat Transfer Coefficients by Use Conditions of Quenching Oil

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Identification of Heat Transfer Coefficients by Use Conditio...

Phosphorylated Salicylic Acid as Flame Retardant in Epoxy Resins and Composites

14～(th) Congress of International Federation for Heat Treament and Surface Engineering

作者： Katsumi Ichitani lubricants research laboratory Idemitsu Kosan Co.Ltd.ChibaJapan

＜正＞ Heat transfer coefficients of the quench medium are necessary for heat-treatment simulation. Cooling characteristics of quenching oil vary with kinds and usage greatly. Users are selecting oil solutions that come up to their desired hardness and quenching distortion requirements. In particular cooling performance rises by agitation and decompression. Therefore we identified a heat transfer coefficient by usage and kinds of quenching oil. Cooling characteristics are different greatly by a kind of quenching oil. A difference of a cooling characteristic by a kind of oil depends on a temperature range of a boiling stage and the maximum heat transfer coefficient mainly. On the other hand, in a convection stage, there are few changes in a boiling stage. Even if quenching oil temperature is changed, heat transfer coefficients do not change greatly. When quenching oil stirred, heat transfer coefficients of vapor blanket stage and a convection stage rise, but there are a few changes in a boiling stage. When quenching oil is decompressed a temperature range of a high heat transfer coefficient moves to the low temperature side. In addition, a heat transfer coefficient in a vapor blanket stage comes down. For precision improvement of heat-treatment simulation, it is important that the heat transfer coefficient is calculated in conformity to the on-site use reality.

关键词： heat transfer coefficient quenching oil heat-treatment simulation

来源： cnki会议评论

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Journal of Renewable Materials 2022年第7期10卷 1931-1950页

作者： Lara Greiner Philipp Kukla Sebastian Eibl Manfred Döring Bundeswehr research Institute for Materials Fuels and LubricantsErding85435Germany Fraunhofer Institute for Structural Durability and System Reliability LBF Darmstadt64289Germany Schill+Seilacher GmbH Böblingen71032Germany

A novel,versatile flame retardant substructure based on phosphorylated salicylic acid(SCP)is described and used in the synthesis of new flame retardants for HexFlowRTM6,a high-performance epoxy resin used in resin transfer molding processes as composite *** starting material salicylic acid can be obtained from natural *** as reactive phosphorus chloride is converted with a novolak,a novolak containing 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide(DOPO)substituents or DOPO-hydroquinone to flame retardants with sufficient thermal stability and high char ***,these flame retardants are soluble in the resin as well as react into the epoxy *** determined thermal stability and glass transition temperatures of flame retarded neat resin samples as well as the interlaminar shear strength of corresponding carbon fiber reinforced composite materials showed the applicability of these flame *** resin samples and composites were tested for their flammability by UL94 and/or flame-retardant performance by cone *** tested flame retardants decrease the peak of heat release rate by up to 54%for neat resin samples.A combination of DOPO and SCP in one flame retardant shows synergistic effects in char formation and the mode of action adapts to neat resin or fiber-reinforced samples,so there is efficient flame retardancy in both ***,a tailoring of SCP based flame retardants is ***,these flame retardants efficiently reduce fiber degradation during combustion of carbon fiber-reinforced epoxy resins as observed by scanning electron microscopy and energy dispersive X-ray spectroscopy.

关键词： Epoxy resin composite fiber protection bio-based flame retardant

Thermal stability of nanocrystalline in surface layer of magnesium alloy AZ91D

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Transactions of Nonferrous Metals Society of China 2010年第7期20卷 1340-1344页

作者：张津欧信兵 Institute of Advanced Material University of Science and Technology Beijing College of Materials Science and Engineering Chongqing University of Technology Nanjing Kerun lubricants Co. Ltd.

Isothermal and isochronal annealing was conducted to study the thermal stability of the nanocrystalline in the surface layer of Mg alloy AZ91D induced by high-energy shot peening(HESP) .Field emission scanning electron microscope(FESEM) and X-ray diffractometer were used to characterize the *** showed that nanocrystalline produced by HESP on the surface layer of the magnesium alloy AZ91D was 60-70 nm on *** nanocrystalline could remain stable at about 100℃,and grew up slowly between 100℃ and 200℃.When the annealing temperature reached 300℃,the growth rate of the nanocrystalline increased *** kinetic coefficient n of the nanocrystalline growth was calculated to be 2-3 and the grain growth activation energy Q=39.7 kJ/mol,far less than the self-diffusion activation energy of magnesium atoms in the coarse polycrystalline material.

关键词： high energy shot peening (HESP) magnesium alloy AZ91D nanoerystalline thermal stability

Lubricating properties of polyalkylene glycol and organic phosphate ester mixed aqueous solutions

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Science China(Technological Sciences) 2013年第12期56卷 2988-2993页

作者： ZHANG ChenHui ZHENG MingWan DAI YuanJing State Key laboratory of Tribology Tsinghua University Shenzhen Key laboratory of Micro-nano Manufacturing Research Institute of Tsinghua University in Shenzhen

Till now,water based lubricants,especially aqueous solutions,have not been employed in the elastohydrodynamic lubrication(EHL)due to their poor film forming capability or low wear *** this paper,we proposed a method to develop water based lubricant:employing polyalkylene glycol solution as base stock to improve EHL film forming capability and using organic phosphate ester(DPZ)as anti-wear additive to improve wear resistance *** lubricating properties of the mixed solutions,including load carrying capability,wear resistance property,friction reduction property,EHL film forming behavior,were *** experimental results indicate that the mixed solution presents excellent lubricating properties,which make it a promising candidate in developing water based lubricants.

关键词： water based lubricant polyalkylene glycol(PAG) organic phosphate ester(DPZ)

Study on the tribological properties of metal rolling bearing under lubrication with diketone lubricants

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Science China(Technological Sciences) 2024年第7期67卷 2003-2017页

作者： DU ShaoNan ZHANG ChenHui LUO Zhi State Key laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Beijing National laboratory of Molecular Sciences CAS Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

In this article, 1-(4-ethylphenyl)-nonane-1,3-dione(0206) was prepared by Claisen condensation. By mixing 0206, chelate, and base oil in a ratio of 3.2:4.8:2, a diketone lubricant(PAO=14(20%)) that can achieve superlubricity was prepared and applied to bearing lubrication experiments. The experimental results show that when the bearing was lubricated by base oil, the friction coefficient(COF) and temperature rise decreased with the decrease of the viscosity of PAO. When PAO=14(20%) was used as the lubricant, the COF of the bearing was the lowest(0.001), and the wear morphology was comparable to that of the bearing lubricated with commercial lubricant. Compared with the base oil with the same viscosity, it is found that the COF and temperature rise of the bearing lubricated by PAO=14(20%) were lower under any experimental conditions. And when the amount of lubricant added was 10 μL, the COF of the bearing lubricated by PAO=14(20%) reached a very low value(0.0004).Bearing ball surface analysis identified the formation of diketone adsorption films. Combined with the previous PAO=14(20%)superlubricity mechanism, it was considered that the occurrence of tribochemical reaction and the bearing effect of chelates were the main reasons for the existence of ultra-low friction coefficient and low wear. In addition, when there were polar molecules in the lubricant, they were adsorbed on the metal surface through tribochemical reactions, resulting in many irregular pits on the surface.

关键词： superlubricity diketone chelate tribochemical recations bearing lubrication