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Effect of Surface Layer Structural-Phase Modification on tribological and Strength Properties of a TiC–(Ni–Cr) Metal Ceramic Alloy

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Acta Metallurgica Sinica(English Letters) 2018年第5期31卷 547-551页

作者： Bao-Hai Yu V.E.Ovcharenko K.V.Ivanov A.A.Mokhovikov Yan-Hui Zhao Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Tomsk Polytechnic University Tomsk 634050 Russia Institute of Strength Physics and Materials Science Siberian Branch of the Russian Academy of Sciences Tomsk 634021Russia

This paper reports TiC–（Ni–Cr） metal ceramic alloy（ratio of components 50：50） with nanoscaled components formed in the surface layer and smoothly transformed into the initial inner structure throughout the material under pulsed electron irradiation of the alloy surface. Principal changes in the surface layer are ascribed to the formation of gradient structure leading to the increase in wear resistance of the surface layer, drop of friction coefficient and improvement of specimen bending resistance when stressing on the irradiated surface side. The above changes of tribological and strength properties in the surface layer under pulsed electron irradiation become more apparent with increasing atomic mass of a plasma-forming inert gas.

关键词： Metal ceramic alloy Particle-reinforced composite Interphase boundaries tribological behavior Bending strength Electron beam treatment

tribological evaluation of environmentally friendly ionic liquids derived from renewable biomaterials

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Friction 2018年第2期6卷 208-218页

作者： Cheng JIANG Weimin LI Jingyan NIAN Wenjing LOU Xiaobo WANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Qingdao Center of Resource Chemistry & New Materials

Unlike most of the conventional ionic liquids(ILs) derived from non-renewable resources, five environmentally friendly ILs([Ch][AA] ILs) derived from amino acids(AAs) and choline(Ch) were synthesized using biomaterials by a simple, green route: acid–base reaction of Ch and AAs. The thermal and corrosion properties, as well as viscosity, of the prepared ILs were examined. The results revealed that the anion structure of ILs plays a dominant role in their thermal and viscosity behavior. These ILs exhibited less corrosion toward copper, related to their halogen-, sulfur-, and phosphorus-free characteristics. The tribological behavior of the synthesized ILs was examined using a Schwingungs Reibung und Verschleiss tester, and the results indicated that these ILs exhibit good friction-reducing and anti-wear properties as lubricants for steel/steel contact. Results from energy-dispersive spectroscopy and X-ray photoelectron spectroscopy indicated that the good tribological properties of [Ch][AA] ILs are related to the formation of a physically adsorbed film on the metal surface during friction.

关键词： choline amino acids ionic liquids lubricant tribological behavior environmentally friendly

Influence of phosphorus on iron-based friction material prepared directly vanadium-bearing titanomagnetite concentrates

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Journal of Iron and Steel Research(International) 2021年第6期28卷 669-678页

作者： Yan-yan Zhang Ke-qin Feng Yue Shui Si-tan Chen Yan-fang Liu School of Mechanical Engineering Sichuan UniversityChengdu 610065SichuanChina

In situ selective carbothermic reactions and vacuum sintering were used to prepare iron-based friction material directly vanadium-bearing titanomagnetite *** of phosphorus addition(0.05–0.20 wt.%)on the microstructure and properties of iron-based friction material were *** results show that the addition of phosphorus improves the microstructure and properties of the material *** phosphorus addition increases to 0.15 wt.%,the sintering densification is promoted and the number of lamellar pearlites ***,the relative density,hardness and tribological properties of the material are greatly ***,the friction coefficient decreases 0.58 to 0.43,and the wear rate reduces 1.829×10^(–7) to 0.694×10^(–7)cm^(3)J^(-1).The dominant wear mechanism of the material changes severe abrasive wear to mild oxidation wear ***,when phosphorus addition exceeds 0.15 wt.%,the matrix continuity and tribological properties of the material are ***,the optimal addition of phosphorus in the iron-based friction material is 0.15 wt.%.

关键词： Vanadium-bearing titanomagnetite concentrate Iron-based friction material tribological behavior Phosphorus

Effect of carbon nanotubes on friction and wear of a piston ring and cylinder liner system under dry and lubricated conditions

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Friction 2017年第2期5卷 147-154页

作者： Zhinan ZHANG Jun LIU Tonghai WU Youbai XIE State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 ChinaSchool of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi'an Jiaotong University Xi'an 710049 China

This study involves the application of carbon nanotubes (CNTs) to a piston ring and cylinder liner system in order to investigate their effect on friction and wear under dry and lubricated conditions. Carbon nanotubes were used as a solid lubricant and lubricant additive in dry and lubricated conditions, respectively. Simulation and measurement of friction and wear were conducted using a reciprocating tribometer. Surface analysis was performed using a scanning electron microscope and an energy dispersive spectrometer. The results indicate that carbon nanotubes can considerably improve the tribological performance of a piston ring and cylinder liner system under dry sliding conditions, whereas improvement under lubricated conditions is not obvious. Under dry friction, the effective time of the CNTs is limited and the friction coefficient decreases with an increase in CNT content. Furthermore, the dominant wear mechanism during dry friction is adhesive.

关键词： carbon nanotubes piston ring tribological behavior friction wear

Characterization and Properties of Duplex a-C:H/MAO Coatings on Magnesium Alloy using Combined Microarc Oxidation and Hybrid Magnetron Sputtering

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Journal of Wuhan University of Technology(Materials Science) 2015年第4期30卷 822-826页

作者：杨巍 DENG Zhennan YANG Zhong LI Jianping 汪爱英 School of Materials Science and Chemical Engineering Xi'an Technological University Ningbo key laboratory of Marine Protection Materials Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Department of Prosthodontics School & Hospital of Stomatology Wenzhou Medical College

The combined microarc oxidation （MAO） and magnetron sputtering deposition process was used to deposit duplex a-C：H/MAO and Ti-a-C：H/MAO coatings on AM80 magnesium alloy. The microstructure, mechanical properties and tribological behavior of the two duplex coatings were investigated. The experimental results showed that the a-C：H and Ti-a-C：H top films on Si substrates were dense and had a low G peak position and ID/IG ratio, compared with the hydrogen-free amorphous carbon films. Numerous micropores were found on the duplex a-C：H/MAO and Ti-a-C：H/MAO coatings together with low values of hardness （H） and elastic modulus （E）, which also showed good binding strength with the Mg alloy substrates. Compared to MAO treated substrate used for the protection of the Mg alloy, the duplex a-C：H/MAO and Ti-a- C：H/MAO coatings still had stable and low value of friction coefficient, even though the surface of the duplex coatings was rough and porous. Furthermore, the mechanism of friction reduction of the two duplex coatings on the Mg alloy substrates was discussed.

关键词： magnesium alloy microarc oxidation hydrogenated amorphous carbon magnetronsputtering tribological behavior

Micro Mechanical and tribological Properties of Auto-Reconditioning Film In situ Generated in Presence of Inorganic Mineral Powders on Worn Metal Surfaces

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Micro Mechanical and Tribological Properties of Auto-Recondi...

Friction and Wear behavior of Ti-6Al-7Nb Biomaterial Alloy

国际材料科学与工程学术研讨会

作者： SHI Pei-jing, XU Yi, YU He-long, XU Bin-shi(National Key Laboratory for Remanufacturing, Academy of Armored Force Engineering, Beijing 100072, China

A special kind of inorganic mineral powders was selected as the auto-reconditioning materials. The crystal structure of the mineral powders was characterized by X-ray diffraction (XRD). A block-on-wheel tribotester was employed to in situ generate protective films on iron-base metal surfaces under designed tribological conditions in presence of superfine inorganic mineral powders which were finely dispersed in lubricant. The morphologies and element distributions of the formed film were observed and determined by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The micro mechanical properties of the protective film were investigated by nanoindentation tester. The results show that the main constitute of the mineral powders formulation chemistry is magnesium silicate hydroxide, Mg(SiO)(OH). After the tribochemical tests, the protective film formed on the worn surface grows to about 1～2 μm, and the micro surface of the protective film is smooth and the surface roughness Ra is better than 50 nm, the film mainly constituted of C, O, Mg with Fe elements. The friction coefficient of the protective film is about 0.055 and nano-hardness of the protective film is increased 35% than ordinary film. The mechanism is inferred that some magnet iron oxide and iron peroxide are dispersed on the habit planes and form the hard ceramic film, which makes small elastic deformations to keep away from surface plastic plowing and adhesion.

关键词： inorganic mineral powders in-situ tribochemical reaction auto-reconditioning film micro mechanical property tribological behavior nanoindendation

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Journal of Biomaterials and Nanobiotechnology 2013年第4期4卷 374-384页

作者： Mamoun Fellah Omar Assala Mohamed Labaiz Leila Dekhil Alain Iost Surface Engineering and Tribology Team Laboratory of Metallurgy and Engineering MaterialsBADJI Mokhtar-Annaba UniversityAnnabaAlgeria Laboratory of Formability and Metallic Materials BADJI Mokhtar-Annaba UniversityAnnabaAlgeria Laboratory of Metallurgy ARTS ET METIERS ParisTechLilleFrance

Titanium has been increasingly applied to biomedical application because of its improved mechanical characteristics, corrosion resistance and biocompatibility. However their application remains limited, due to the low strength and poor wear resistance of unalloyed titanium. The purpose of this study is to evaluate the friction and wear behavior of high-strength titanium alloys: Ti-6Al-7Nb used in femoral stem (total hip prosthesis). The oscillating friction and wear tests have been carried out in ambient air with oscillating tribotester in accord with standards ISO 7148, ASTM G99-95a, ASTM G 133-95 under different conditions of normal applied load (3, 6 and 10 N) and sliding speed (1, 15 and 25 mm.s-1), and as a counter pair we used the ball of 100C 6, 10 mm of diameter. The surface morphology of the titanium alloys has been characterized by SEM, EDAX, micro hardness, roughness analysis measurements. The behavior observed for both samples suggests that the wear and friction mechanism during the test is the same for Ti alloys, and to increase resistance to wear and friction of biomedical titanium alloys used in total hip prosthesis (femoral stems) the surface coating and treatment are required.

关键词： tribological behavior Friction and Wear Tests Biomaterial Total Hip Prosthesis Ti-6Al-7Nb

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聚醚醚酮/改性纳米石墨微片复合材料的研究

聚醚醚酮/改性纳米石墨微片复合材料的研究