Regulation on tribological performance of tungsten-doped DLC coatings by Choline Chloride-Urea and -Thiourea Deep Eutectic Solvents

2022 ◽  
Author(s):  
Fan Yang ◽  
Yuting Li ◽  
Zhaofan Yue ◽  
Qingbo Fan ◽  
Hao Li ◽  
...  
Keyword(s):  
Surface Properties ◽  
Friction And Wear ◽  
Choline Chloride ◽  
Deep Eutectic Solvents ◽  
Tribological Performance ◽  
Lubrication System ◽  
Low Friction ◽  
Dlc Coatings ◽  
Solid Liquid ◽  
Tribochemical Interaction

Abstract Solid-liquid composite lubrication system has attracted an increased interest for low friction and wear. Nevertheless, the effect of mechanical and surface properties of the solid materials, especially the mechanical and surface properties governed by doping elements, on the tribological performance solid-liquid composite lubrication system is still not well comprehended. Here, we reported the effect of W content on the mechanical and surface properties of W-DLC coatings as well as the tribological properties of W-DLC coatings under (choline chloride-urea and choline chloride-thiourea) deep eutectic solvents lubrication. Although the wear of W-DLC coatings under dry friction increases with W content, the wear under DESs is slight when coatings show excellent wettability to DESs or a DES-derived tribochemical film is formed. We demonstrate that the tribological behavior of W-DLC and DESs composite lubrication system is related to the mechanical properties of W-DLC coatings together with the contact angle and tribochemical interaction between DESs and W-DLC coatings.

The tribological performance of W-DLC in solid–liquid lubrication system addivated with Cu nanoparticles

2021 ◽  
Author(s):  
Dong shan Li ◽  
Ning Kong ◽  
Ruishan Li ◽  
Boyang Zhang ◽  
Yongshun Zhang ◽  
...  
Keyword(s):  
Test Temperature ◽  
Applied Load ◽  
Tribological Performance ◽  
Dominant Factor ◽  
Lubrication System ◽  
Cu Nanoparticles ◽  
Friction Test ◽  
Dlc Film ◽  
Test Conditions ◽  
Solid Liquid

Abstract Judicious selection of additives having chemical and physical compatibility with the DLC films may help improving the triboligical properties and durability life of DLC-oil composite lubrication systems. In this study, Cu nanoparticles were added to PAO6 base oil to compose a solid-liquid composite lubrication system with W-DLC film. The effects of nanoparticle concentration, test temperature and applied load on tribological performance were systematically studied by a ball-on-disk friction test system. The tribological results illustrated that Cu nanoparticles could lower the coefficient of friction (COF) and dramatically reduce the wear rates of W-DLC films. The optimal tribological behavior was achieved for the 0.1 wt.% concentration under 30 ℃ and the applied load of 100 N. The test temperature and applied load were vital influencing factors of the solid–liquid lubrication system. The bearing effect and soft colloidal abrasive film of spherical Cu nanoparticle contributed to the excellent tribological performance of the composite lubrication system under mild test conditions, meanwhile, the local delamination of W-DLC film and oxidation were the main causes of the friction failure under harsh test conditions. With test temperature and applied loads increase the degree of graphitization of the W-DLC film increased. In conclusion, there are several pivotal factors affecting the tribological performance of solid–liquid lubrication systems, including the number of nanoparticles between rubbing contact area, graphitization of the worn W-DLC films, tribofilms on the worn ball specimens and oxidation formed in friction test, and the dominant factor is determined by the testing condition.

Investigation of PVD Piston Ring Coatings With Different Lubricant Formulations

2017 ◽  
Author(s):  
Eduardo Tomanik ◽  
Hiroshi Fujita ◽  
Shinya Sato ◽  
Eliel Paes ◽  
Ciro Galvao ◽  
...  
Keyword(s):  
Friction And Wear ◽  
Piston Ring ◽  
Superior Performance ◽  
Low Friction ◽  
Dlc Coatings ◽  
Low Viscosity ◽  
Lubricant Oil ◽  
Wear And Friction ◽  
Oil Formulation ◽  
Urban Conditions

Chromium nitride (CrN) is the main protecting coating applied to top rings for gasoline and diesel engines, due to its excellent wear resistance, low friction and minor environmental impacts, especially in modern engines operating with low viscosity oils. Recently, diamond like carbon (DLC) coatings reported improved tribological performance, but at a higher cost. Therefore, in the present work, wear and friction of CrN and DLC coated rings were evaluated on reciprocating and floating liner engine tests running on 0W-20 and 0W-16 lubricant formulations, which additives tailored for different markets (Japanese, European and Emerging). DLC outperformed CrN for both friction and wear when running on lubricant formulations without molybdenum additives. On opposite, with high molybdenum content additives, CrN presented synergic effects that significantly reduced friction and wear, whilst DLC did not. Same comparison on floating liner engine tests demonstrated again superior performance of CrN by 9% reduction on friction losses, running on oils containing molybdenum additives, whilst DLC lowered 6%. From that, it can be estimated 0.4% fuel saving at urban conditions by combining Japanese lubricant oil formulation and CrN top rings.

scholarly journals Green and Efficient Extraction of Resveratrol from Peanut Roots Using Deep Eutectic Solvents

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Jingnan Chen ◽  
Xingxing Jiang ◽  
Guolong Yang ◽  
Yanlan Bi ◽  
Wei Liu
Keyword(s):  
Choline Chloride ◽  
Deep Eutectic Solvents ◽  
Extraction Yield ◽  
Box Behnken Design ◽  
Assisted Extraction ◽  
Ultrasonic Assisted ◽  
Efficient Extraction ◽  
Ultrasonic Assisted Extraction ◽  
Solid Liquid ◽  
Total Extraction

Deep eutectic solvents (DESs), a new group of ecofriendly solvent combined with the ultrasonic-assisted extraction (UAE) technique, were first successfully used for extraction of resveratrol from peanut roots. Resveratrol in the extract was analyzed and quantified using a HPLC-UV method. A series of DESs consisting of choline chloride (ChCl) and 1,4-butanediol, citric acid, and ethylene glycol were formulated, finding ChCl/1,4-butanediol was a most proper extraction system. The optimal extraction parameters were obtained using a Box–Behnken design (BBD) test combined with response surface methodology as follows: 40% of water in ChCl/1,4-butanediol (1/3, g/g) at 55°C for 40 min and solid/liquid ratio of 1:30 g/mL. The total extraction content and extraction yield of resveratrol from peanut roots could reach 38.91 mg/kg and 88.19%, respectively, under such optimal conditions. The present study will provide a typical example for using DESs to extract natural bioactive compounds from plants.

Tribological Performance of Polymer-Based Coatings for Oil-Less Piston-Type Compressor Applications

2010 ◽  
Author(s):  
Seung Min Yeo ◽  
Emerson Escobar Nunez ◽  
Andreas A. Polycarpou
Keyword(s):  
Friction And Wear ◽  
Gray Cast Iron ◽  
Wear Behavior ◽  
Tribological Performance ◽  
Polymeric Coatings ◽  
Low Friction ◽  
Reliable Operation ◽  
Interacting Surfaces ◽  
Current Research Interest ◽  
Better Than

Due to thermodynamically adverse effects of liquid-type lubricants on the operation of air conditioning and refrigeration compressors, oil-less compressors are of current research interest. Under such conditions, advanced tribologically coatings are needed for critical interacting surfaces to ensure reliable operation under oil-less conditions. In this paper, seven commercially available polymeric coatings (PTFE-, PEEK-, resin- and fluorocarbon-based coatings) coated on gray cast iron were tribologically evaluated through unlubricated oscillatory experiments simulating a realistic wrist pin interface in a piston-type compressor. The experiments were performed in the presence of the environmentally friendly (as far as minimal global warming potential is concerned) carbon dioxide refrigerant, simulating oil-less piston-type compressors. It was found that polymer-based coatings exhibited excellent tribological performance, and in general PTFE-based coatings performed better than PEEK-based coatings. Also, their friction and wear behavior is affected by additives, which polymeric coatings were blended with. Specifically, PTFE coatings blended with pyrrolidone showed relatively low friction coefficient, and coatings blended with MoS2 had higher wear resistance.

The tribological performance of DLC-based coating under the solid–liquid lubrication system with sand-dust particles

Wear ◽  
2013 ◽  
Vol 297 (1-2) ◽  
pp. 972-985 ◽  
Author(s):  
Jianwei Qi ◽  
Liping Wang ◽  
Fengyuan Yan ◽  
Qunji Xue
Keyword(s):  
Tribological Performance ◽  
Dust Particles ◽  
Lubrication System ◽  
Solid Liquid ◽  
Sand Dust

scholarly journals Application of Natural Deep Eutectic Solvents in the Extraction of Quercetin from Vegetables

Molecules ◽  
2019 ◽  
Vol 24 (12) ◽  
pp. 2300 ◽  
Author(s):  
Yunliang Dai ◽  
Kyung Ho Row
Keyword(s):  
Choline Chloride ◽  
Chemical Properties ◽  
Deep Eutectic Solvents ◽  
Research Attention ◽  
Natural Deep Eutectic Solvents ◽  
Significant Research ◽  
Prevention And Health Promotion ◽  
Ultrasonic Assisted ◽  
Solid Liquid ◽  
Physical And Chemical

Quercetin is a phytochemical with disease prevention and health promotion activities that has attracted significant research attention. In this study, choline chloride and betaine-based natural deep eutectic solvents were prepared using a heating method. Their physical and chemical properties were also tested. Then, they were applied to extract quercetin from onion and broccoli with ultrasonic-assisted solid liquid method coupled with HPLC. Three factors (temperature, amount, and time) were considered for the optimization of the extraction assays. In the optimal conditions, the extraction recoveries were 88.91–98.99%, 88.45–99.01%, and 89.56–98.74% for quercetin, isorhamnetin, and kaempferol. Tailor-made natural deep eutectic solvents could be applied as sustainable and safe extraction media for biochemical applications.

Friction and Wear Behavior Evaluation of DLC Films Grown in Multilayer of Carbon and Silicon

2014 ◽  
Vol 802 ◽  
pp. 392-397
Author(s):  
Patrícia Cristiane Santana da Silva ◽  
Gislene Valdete Martins ◽  
Evaldo José Corat ◽  
Vladimir Jesus Trava-Airoldi
Keyword(s):  
Friction Coefficient ◽  
Friction And Wear ◽  
Wear Behavior ◽  
High Hardness ◽  
Low Friction ◽  
Dlc Coatings ◽  
Hard Materials ◽  
Dc Discharge ◽  
Pulsed Dc ◽  
Pulsed Dc Discharge

Excellent tribological properties of hard materials surface are desirable in several sectors of industry. Diamond-like carbon (DLC) coatings are well known for their low friction, excellent wear resistance, and high hardness. In this work, DLC films were deposited on AISI M2 steel using a modified PECVD pulsed-DC discharge. Multilayer of carbon and silicon were grown, alternately. Samples were produced with different layer thickness for carbon and silicon, and the same parameters for each material layer, in order to investigate friction coefficient in each layer, evaluate rate deposition variation and the gradient behavior of different layers. Raman spectroscopy was used to verify the structural arrangement of carbon atoms. The films were also characterized by scanning electron microscopy and EDX. Tribological tests were performed to observe adhesion between layers and substrate, friction, and wear. The results showed the variation of friction coefficient and that deposition rate declines when increasing number of layers.

Tribological behavior of WS2-based solid/liquid lubricating systems dominated by the surface properties of WS2 crystallographic planes

RSC Advances ◽  
2015 ◽  
Vol 5 (80) ◽  
pp. 64892-64901 ◽  
Author(s):  
Xin Quan ◽  
Xiaoming Gao ◽  
Lijun Weng ◽  
Ming Hu ◽  
Dong Jiang ◽  
...  
Keyword(s):  
Surface Properties ◽  
Wear Mechanism ◽  
Tribological Behavior ◽  
Tribological Performance ◽  
Composite Systems ◽  
Liquid Systems ◽  
Crystallographic Planes ◽  
Solid Liquid

WS2-based solid/liquid systems were established successfully by combining pure WS2 films with different oil-based liquid lubricants. The tribological performance, adsorption and wear mechanism of the composite systems were investigated.

scholarly journals Effect of Bias Voltage on Microstructure and Properties of Tantalum Nitride Coatings Deposited by RF Magnetron Sputtering

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 911
Author(s):  
Wei Dai ◽  
Yunzhan Shi
Keyword(s):  
Magnetron Sputtering ◽  
Bias Voltage ◽  
Rf Magnetron Sputtering ◽  
Amorphous Structure ◽  
Tribological Performance ◽  
Tantalum Nitride ◽  
Growth Morphology ◽  
Low Friction ◽  
Nitride Coatings ◽  
Overall Performance

TaNx coatings were deposited by RF magnetron sputtering with different bias voltages. The growth morphology, crystalline structure, chemical bond structure, hardness and elastic modulus, adhesion strength and tribological performance of the coatings were studied as a function of the bias voltage. The results showed that an increasing bias voltage refines the coating grains and facilitates structure densification. Simultaneously, the structure of the TaNx coatings transfers from a composite structure consisting of TaN and Ta2N crystals, through a single composite mainly composed of the Ta2N crystal, to an amorphous structure as the bias voltage increases from low to high, indicating that the phase composition of the TaNx coatings can be varied by the bias voltage. The coating composed of Ta2N crystal showed a good overall performance including enhanced hardness, enhanced adhesive strength, and good tribological performance with enhanced wear resistance and a low friction coefficient of 0.18.

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