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Bionic Coupling of Hardness Gradient to Surface Texture for Improved anti-wear Properties

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Journal of Bionic Engineering 2016年第3期13卷 406-415页

作者： Long Zheng Jianjun Wu Si Zhang Shishuai Sun Zhihui Zhang Song Liang Zhenning Liu Luquan Ren Key Laboratory of Bionic Engineering (Ministry of Education) College of Biological and Agricultural Engineering Jilin University Changchun 130022 China

This work investigates the potential of combining hardness gradient with surface texture （an example of bionic coupling） to improve anti-wear properties. The bionic coupling of hardness gradient and Hexagonal Texture （HT） was achieved by laser heat treatment on steel specimens with pre-engraved hexagonal surface texture. The successful establishment of decreasing hardness from surface to internal bulk was verified by hardness measurements along the depth of cross-sectioned specimens and corre- lated with the observations from metallurgical microscopy. The tribological performance of bionic coupling specimens （HT-L） was examined under dry contact condition, together with respective control specimens of individual bionic features, e.g. HT-H （of similar surface hardness generated by conventional heat treatment but without hardness gradient） and SS-L （of smooth surface treated by the same laser processing as for HT-L）. It is found that HT-L not only exhibits lower friction coefficient and less friction fluctuation than HT-H and SS-L, but also demonstrates a 〉50% reduction of wear loss compared to HT-H and SS-L （0.0343 g for HT-L vs. 0.0723 g for HT-H, P〈0.001; 0.0343 g for HT-L vs. 0.0817 g for SS-L, P〈0.001）. Corroboratively, observations with scanning electron microscopy revealed a relatively smooth surface for worn HT-L specimen, contrasting with the rugged and grooved surfaces of worn HT-H and SS-L specimens. These results indicate that the bionic coupling of hardness gradient to hexagonal texture can indeed improve anti-wear properties, affording a new strategy to wear and friction manage- ment.

关键词： anti-wear bionic coupling hardness gradient surface texture hexagonal texture

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

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Friction 2024年第3期12卷 439-451页

作者： Yixin WANG Qi LU Huijie XIE Shujuan LIU Qian YE Feng ZHOU Weimin LIU State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

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.

关键词： lubricant additives hypercrosslinked polystyrene carbon nanospheres friction reduction anti-wear

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

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Chinese Journal of Mechanical Engineering 2017年第3期30卷 644-651页

作者： Norzahir Sapawe Syahrullail Samion Mohd Izhan Ibrahim Md Razak Daud Azli Yahya Muhammad Farhan Hanafi universiti kuala lumpur malaysian institute of chemical and bioengineering technologyLot 1988 Vendor CityTaboh NaningAlor Gajah78000 MelakaMalaysia faculty of mechanical engineering universiti teknologi malaysiautm johor bahru81310 JohorMalaysia politeknik tuanku sultanah bahiyah(politeknik kulim) Kulim Hi-Tech Park09000 KulimMalaysia faculty of biosciences and medical engineering universiti teknologi malaysiautm johor bahru81310 JohorMalaysia

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.

关键词： anti-wear anti-friction Bio-lubricant Palmoil Titanium pin

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

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China Petroleum Processing & Petrochemical Technology 2019年第2期21卷 95-102页

作者： Xie Xin Jia Qiulian Zhang Jianrong SINOPEC Research Institute of Petroleum Processing

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.

关键词： engine oil GF-6 Sequence IVB anti-wear valvetrain wear

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

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China Petroleum Processing & Petrochemical Technology 2017年第2期19卷 74-79页

作者： Li Yi Liu Xinyang Liu Dajun Sun Hongwei China Petroleum & Chemical Corporation Beijing 100728 SINOPEC Research Institute of Petroleum Processing Beijing 100083

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%.

关键词： TiO2 nanoparticles lubricating grease anti-wear anti-friction

Experimental Study on Friction Reducing and anti wear Property of a Water-Based Lubricant with Polyether Added

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稀有金属材料与工程 2012年第S1期41卷 276-279页

作者： Zhang Chaohui Liu Sisi Liu Junming Beijing Jiaotong Univ Sch Mech Elect & Control Engn Beijing 100044 Peoples R China

The wear behaviors of steel-steel pair on condition of a water-based lubricant with copolymer of acylamino polyoxyethylene polyoxypropylene ether(KE-1)included as additives are investigated with the help of the universal micro-tribotester.Tests on friction and wear are carried out.As a reference,some tests with pure water are also performed for comparison.The results show that the prepared water-based lubricant has a good effect on the characteristics associated with friction reducing and anti-wear processes,which lay some credence to its utilization in practical industrial tribo-systems.

关键词： acylamino-polyoxyethylene-polyoxypropylene-ether water-based lubricant anti-wear property

anti-wear properties on 20CrMnTi steel surfaces with biomimetic non-smooth units

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Science China(Technological Sciences) 2010年第11期53卷 2920-2924页

作者： HU Yong HAN ZhiWu XU MingXu ZHANG ZhiHui College of Mechanical Science and Engineering Nanling CampusJilin UniversityChangchun 130025China Key Laboratory of Bionic Engineering Ministry of EducationCollege of Biology and Agriculture EngineeringNanling CampusJilin UniversityChangchun 130025China

In order to gain a sufficient wear resistance for applications, the biomimetic non-smooth units in concave were fabricated on the surfaces of 20CrMnTi steel using a biomimetic laser remelting technology. The diameter and distribution of the concaves were optimized using orthogonal experiment. The microstructures of the biomimetic non-smooth units were examined. The anti-wear behaviors were investigated by the rolling wear test with lubricant. The results of wear tests indicated that the biomimetic surfaces exhibit a higher anti-wear ability than the smooth surfaces. The biomimetic surface with concaves of 250 μm in diameter and transverse distance of 270 μm and longitudinal distance of 400 μm exhibits the best anti-wear property. The enhancement of wear resistance can be mainly attributed to the action of biomimetic non-smooth units and the super fined microstructure and hardness in the biomimetic unit zones.

关键词： biomimetic unit concave orthogonal experiment anti-wear 20CrMnTi

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

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Journal of Wuhan University of Technology(Materials Science) 2006年第3期21卷 79-81页

作者：文庆珍 College of Science Naval University of EngineeringWuhan 430033China

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.

关键词： lubrication anti-wear extreme pressure organo-molybdenum compound boundary film

Ultralow friction PTFE/PEEK heterolayer:A new solid lubrication approach toward simplicity

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Friction 2024年第1期12卷 120-135页

作者： Wei SUN Jiaxin YE Qingrui SONG Yi FENG Xiaojun LIU School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Institute of Tribology School of Mechanical EngineeringHefei University of TechnologyHefei 230009China

Tribological applications of polytetrafluoroethylene(PTFE)are often limited by technological complexity to overcome its poor wear resistance.Here,a PTFE/polyetheretherketone(PEEK)heterolayer(HL)was proposed and evaluated as a new solid lubrication solution.Pin-on-disk tribometry found the lowest friction coefficient(μ)of 0.031 and ultralow wear for the PEEK/HL under typical conditions.The friction coefficient of the HL surpasses those of the state-of-the-art polymeric coatings/composites by at least 200%,and approaches that of highly lubricated interfaces.Mechanistic investigations revealed multi-length physical and chemical heterogeneity of the HL that best facilitates a tribofilm with high subsurface stability and surface instability.The technological simplicity and robustness of the HL’s high lubricity make it a promising new type of solid lubrication toward greater reliability and longevity.

关键词： ultralow friction anti-wear polytetrafluoroethylene(PTFE) heterolayer(HL)