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Friction-reducing and antiwear behavior of metal halide-stabilized linear phosphazene derivatives as lubricants for a steel-on-steel contact

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Science china(Technological sciences) 2005年第3期48卷 282-291页

作者： ZHU Jiamei 1,2., LIU Weimin 2.& LIANG Yongmin 2.1. School of chemical Engineering and Technology, china University of Mining and Technology, Xuzhou 2.1008, china 2. state key Laboratory of solid lubrication, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china 1. School of chemical Engineering and Technology China University of Mining and Technology 221008 Xuzhou China 2. state key Laboratory of {2. lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences 730000 Lanzhou China

A series of novel metal halide-stabilized linear phosphazene derivatives were synthesized. The friction-reducing and antiwear abilities of the resulting products as the lubricants for a steel-on-steel contact were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn steel surface was observed on a scanning electron microscope, while the chemical states of some typical elements on the worn steel surface were examined by means of X-ray photoelectron spectroscopy. It was found that both the side branch structures and central metals influenced the friction-reducing and antiwear behaviors of the synthetic derivatives as the lubricants, which was related to the different adsorption activities of the organic compounds composed of different organic ingredients and metallic ions on a nascent metal surface. All the synthetic lubricants except for the iron (III) derivative showed increased antiwear abilities with increasing metallic ionic radius. A protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic fluorine compounds, nitrogen oxide, and Fe 3 (PO 4 ) 2.plays an important role in improving the friction and wear behavior of the steel-on-steel system.

关键词： metal halide-stabilized linear phosphazene derivatives,lubricant,steel,tribological properties.

Preparation and Characterization of ZrO_2.Nanoparticles Capped by Trioctylphosphine Oxide (TOPO)

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Journal of Wuhan University of Technology(Materials Science) 2011年第4期26卷 611-614页

作者：马剑琪 School of Chemistry and Environmental Science Shaanxi University of Technology state key Laboratory of {2. lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

Monodisperse ZrO2.nanoparticles capped by trioctylphosphine oxide （TOPO） were prepared in non-aqueous solvent using in-situ synthesis method. Transmission electron microscopy（TEM）, X-ray diffraction（XRD）, X-ray photoelectron spectrometer（XPS）, Fourier transformation infrared spectroscopy （FTIR）, and thermogravimetric analysis（TGA） were adopted to characterize and investigate the size, structure, composition, and the binding manners between organic capping agent TOPO and inorganic ZrO2.nanocores of the as-prepared nanoparticles. In addition, the nanoparticles were also studied to determine their solubility and relative stability. The experimental results show that the prepared nanoparticles contain about 2.% organic capping shell TOPO, 75% inorganic ZrO2.nanocores, and can be easily dissolved and be stably disersed in non-polar organic solvents.

关键词： ZrO2.nanoparticles trioctylphosphine oxide (TOPO) monodisperse solubility

Progress and development in thermodynamic theory of friction and wear

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Science china(Technological sciences) 2009年第4期52卷 844-849页

作者： DAI ZhenDong1 & xue qunji2.1 {2. of Bio-inspired Structure and Surface Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 2.0016, china 2.state key Laboratory of solid lubrication, chinese academy of sciences, lanzhou 710000, china 1. institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China 2. state key Laboratory of {2. lubrication Chinese Academy of Sciences Lanzhou 710000 China

Tribology theory lags well behind engineering needs because of those complex and multi-dimensional characteristics associated with friction and wear. The mechanism of friction is reviewed and discussed from a static thermodynamics perspective; research methods on the process of friction and wear and thermodynamic studies within the field of tribology are also reviewed. We propose that entropy can be a critical parameter in describing the evolution of friction and wear, and the entropy balance equation could be considered as a fundamental cornerstone for a systematic tribology theory. Applications of irreversible thermodynamic theory of tribology to various fields are reviewed.

关键词： friction and wear irreversible thermodynamics entropy generation multi-factor coupling

Wear Behavior of Cu Matrix Composites Reinforced with Mixture of Carbon and Carbon Nanotubes

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 254-257页

作者：姜金龙 School of Science Lanzhou University of Technology state key Laboratory of {2. lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

In order to improve wear resistance and decrease the cost, carbon and carbon nanotubes reinforced copper matrix composites were fabricated by the power metallurgy method. The effects of carbon （carbon and carbon nanotubes） volume fraction and applied load on the friction coefficient and wear rate under dry sliding of the composites were investigated at room temperature. By scanning electron microscopy （SEM）, the worn surfaces and debris were observed, and wear mechanism was also analyzed and discussed. The experimental wear process consists of the run-in, steady wear and severe wear process with the increasing of sliding distance. Both the friction coefficient and wear rate of the composites first decrease and then increase with the increasing of carbon volume fraction. The minimum friction coefficient and wear rate are obtained when carbon is 4.0vo1%. The wear mechanisms of the composites change from the adhesive wear and delamination wear to abrasive wear with the increasing of carbon volume fraction.

关键词： C/Cu matrix composite power metallurgy wear behavior

Microstructure and Wear Resistance Evolution of HVOFSprayed WC-(W,Cr)_2.-Ni Coating with Post Heat Treatment In Air Atmosphere

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稀有金属材料与工程 2012年第S1期41卷 388-393页

作者： Hou Guoliang1,2.Zhou Huidi1,An Yulong1,2.Liu Guang1,2.Chen Jianmin1,Chen Jie1,2.1 state key Laboratory of {2. lubrication,lanzhou institute of chemical physics,chinese academy of sciences,lanzhou {12.,china 2.Graduate University,chinese academy of sciences,Beijing 100049,china chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

WC-(W,Cr)2.-Ni coating was prepared on 1Cr18Ni9Ti stainless steel and C-2.6 Ni-base Hastelloy by high velocity oxy-fuel(HVOF)*** effect of post heat treatment in air atmosphere on the microstructure,phase composition,microhardness,fracture toughness,and wear resistance of HVOF-sprayed WC-(W,Cr)2.-Ni coating was *** microstructure and phase composition of the coatings were analyzed by means of field emission scanning electron microscopy(FESEM)and X-ray diffraction(XRD).The microhardness and fracture toughness of the coatings were measured using a microhardness tester and a Vickers hardness ***,dry friction and wear behavior of the coatings sliding against Si3N4 ball was investigated using an oscillating friction and wear tester;and the worn surfaces of the coatings were analyzed by means of scanning electron microscopy(SEM).It was found that heat treatment within 500-800°C resulted in crystallization of amorphous phase in as-sprayed coating,generating nanoscale new phases such as NiWO4,CrWO4 and ***,heat treatment led to increase of the microhardness of as-sprayed coating,and the highest microhardness was obtained after heat treatment at 800°*** fracture toughness and wear resistance of the as-sprayed coating increased with increasing heat treatment temperature up to 700°C but tended to decrease with further elevating *** other words,the mechanical properties and wear resistance of the as-sprayed coatings were worsened owing to excessive growth of oxidation grains and depletion of ductile Ni binder after heat treatment above 700°*** it was suggested that as-sprayed ceramic composite coating should be post heat treated in air at a moderate temperature of 700°C so as to achieve the optimized mechanical properties and wear resistance.

关键词： HVOF WC-(W,Cr)2.-Ni coating post heat treatment microstructure wear resistance

Patterned self-assembled film guided electrodeposition

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Science china Chemistry 2004年第2期47卷 120-125页

作者： ZHOU Feng1, LI Bin1,2. XU Tao1, CHEN Miao1, HAO Jingcheng1 & LIU Weimin1 1. state key Laboratory of {2. lubrication, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china 2. Department of Chemistry, Shandong institute of Education, Jinan 2.0014, china 1. state key Laboratory of {2. lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences 730000 Lanzhou China 2. Department of Chemistry Shandong Institute of Education 250014 Jinan China

The paper describes the fabrication of polypyrrole (PPy) microstructures through patterned self-assembled film guided electrodeposition. Thus the patterned self-assembled monolayer is prepared by microcontact printing (μCP) and used as the template in the electrodeposition of PPy. It has been found that the self-assembled monolayer plays completely different roles on different substrates in directing the deposition of the PPy. Namely, the electrodeposition mainly occurs on the exposed area of the gold substrates patterned with dodecanethiol (DDT) and octadecanelthiol (ODT) and on the indium tin oxide (ITO) substrate patterned with octadecyltrichlorosilane (OTS), while PPy nucleates on the OTS covered area and no deposition is found on the exposed area of a semiconductor substrate (silicon). This is attributed to the co-operative effect between the substrate conductivity and the compatibility of the PPy oligomerwith the covered or exposed area of the substrate surface.

关键词： pattern, conducting polymer, microcontact printing, electrodeposition.

Studies on the Reaction Mechanism of CO_2.Reforming of Methane over Co/γ-Al_2._3 Catalyst

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chinese chemical Letters 1997年第2期8卷 121-124页

作者： Yong LU Chang Chun YU Jin Zhen xue Yu LIU xue Jia DING and Shi Kong SHEN({2. key Laboratory of Oxo Synthesis and Selective Oxidation,lanzhou institute of chemical physics,chinese academy of sciences. lanzhou 730000) chinese ACAD SCI LANZHOU INST CHEM PHYSSTATE KEY LAB OXO SYNTH & SELECT OXIDATLANZHOU 730000PEOPLES R CHINA

TPPR and XPS characterizations were combined to study the reaction mechanism of CO2.eforming of methane to syngas over Co/γ-Al2.3 catalysts. CH4 shows a tendency to form surface carbons by deep dissociation at high temperatures. CO2.dissociation reaction also occurs at >673K. It is believed that carbide carbons are active species to generate CO by rcacting with o atoms dissociated from CO2. In the reaction,Co(0) particles are responsible for dissociating CH4 to form active C. abstracting an O atom from CO2.molecule, and transferring O atom to C to form CO.

关键词： over CO Al2.3 Catalyst Studies on the Reaction Mechanism of CO2.Reforming of Methane over Co

The thermal stability and tribological properties of cadmium dithiomolybdenate at evaluated temperature

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Science china Mathematics 2001年第S1期44卷 163-170页

作者： LIU Weimin FENG Dapeng state key Laboratory of {2. lubrication, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China

CdMoO_2._2.H_2. was synthesized in laboratory. Its thermal stability was investigated by means of Th ermog ravimetric analysis (TGA), and its tribological characteristics at temperatures up to 500℃ were examined by sliding a Sialon ceramic and GCr15(AIS152.00) steel ball against a W18Cr4V(AISI T1) steel disc on a high temperature ball-on-disc tribometer. The morphologies of and the elemental distributions in the worn surfaces of the ceramic and GCr15 ball were observed and determined by scanning electron microscopy (SEM) equipped with energy dispersion spec- trometry (EDS). The chemical states of some typical elements in the worn surfaces of the ceramic ball and steel ball were explored with X-ray photoelectron spectroscopy (XPS). As the results, CdMoO_2._2.showed good lubricity for Sialon ceramic/W18Cr4V steel and GCr15/W18Cr4Vpair from room temperature to 400℃. The XPS analytical results indicate that CdMoO_2._2.experienced tribochemical reactions during the friction process at 300℃, thereby generating S and Mo of higher valence for both pair. While for GCr15/W18Cr4V pair, produced MoS_2. SEM observations of the worn surfaces of the Sialon ceramic and GCr15 ball show that a surface protective film composed of the lubricants and their decomposed products was formed thereon, which contributes to keep the sliding surfaces off contact and abate the adhesion and scuffing on the lubricated surfaces, therefore to decrease the friction coefficients.

关键词： cadmium dithiomolybdenate high temperature tribochemical reaction transfer film

Fabrication of Transparent Superhydrophilic TiO_2.Nanofilm without UV-irradiation

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稀有金属材料与工程 2012年第S1期41卷 263-267页

作者： Du Wen1,2.Ye Yinping1,Li Hongxuan1,Zhao Fei1,2.Ji Li1,Quan Weilong1,2.Chen Jianmin1,Zhou Huidi1 1 state key Laboratory of {2. lubrication,lanzhou institute of chemical physics,chinese academy of sciences,lanzhou {12.,china 2.Graduate University of chinese academy of Science,Beijing 100049,china chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

A transparent phase-pure anatase TiO2.nanofilm was prepared through magnetron sputtering method,and a subsequent annealing treatment awarded it the superhydrophilic *** make clear the mechanism of the heat-induced superhydrophilicity,the chemical composition and surface morphology of the film were investigated in detail and compared before and after the annealing treatment mainly by field emission scanning electron microscopy(FESEM),X-ray diffraction method(XRD),Raman spectroscopy,and X-ray photoelectron spectroscope(XPS).The results suggest that the probable mechanism is in accordance with the UV-induced mechanism,where the heat-induced surface oxygen vacancies and hydroxyl radicals play important roles for achieving the superhydrophilicity.

关键词： superhydrophilicity transparent TiO2 nanofilms magnetron sputtering annealing treatment