Sonication-Assisted Solvothermal Synthesis of Noncovalent Fluorographene/Ceria Nanocomposite with Excellent Extreme-Pressure and Anti-Wear Properties

2021 ◽  
pp. 106991
Author(s):  
Limin Ma ◽  
Zhangpeng Li ◽  
Kaiming Hou ◽  
Weihong Jia ◽  
Jinqing Wang ◽  
...  
Keyword(s):  
Solvothermal Synthesis ◽  
Extreme Pressure ◽  
Wear Properties

Friction and Wear Properties of Laser Cladding Coatings under Boundary Lubrication Conditions

2011 ◽  
Vol 314-316 ◽  
pp. 143-146
Author(s):  
Xin Feng ◽  
Yan Qiu Xia
Keyword(s):  
Phase Composition ◽  
Laser Cladding ◽  
Friction And Wear ◽  
Liquid Paraffin ◽  
Extreme Pressure ◽  
Wear Properties ◽  
Aisi 52100 ◽  
Aisi 1045 ◽  
Aisi 52100 Steel ◽  
Friction And Wear Properties

AISI 1045 steels were laser-clad with Ni-based powder by CO2 HJ-4 coherent laser. The phase composition of the laser-cladding coating was investigated by means of X-ray diffraction (XRD). The cross-section of the cladding coating was observed using a scanning electron microscopy (SEM). The friction and wear properties of the laser cladding coatings sliding against AISI 52100 steel under the lubrication of liquid paraffin containing various anti-wear and extreme pressure additives were investigated using an Optimol SRV reciprocating motion friction and wear tester. Results showed that the laser-cladding coating considerably decreased coefficient of friction and increased wear resistance in sliding against AISI 52100 steel and attributed to the change in the hardness, phase composition of the laser-cladding coating and tribochemical reactions between the laser-cladding coating and the extreme pressure and anti-wear additives.

BPNN-QSTR Models for Triazine Derivatives for Lubricant Additives

2019 ◽  
Vol 142 (1) ◽  
Author(s):  
Tingting Wang ◽  
Zhan Wang ◽  
Hao Chen ◽  
Kang Dai ◽  
Xinlei Gao
Keyword(s):  
Tribological Properties ◽  
Back Propagation ◽  
Three Dimensional ◽  
Predictive Ability ◽  
Quantitative Relationship ◽  
Molecular Structures ◽  
Lubricant Additives ◽  
Extreme Pressure ◽  
Wear Properties ◽  
Triazine Derivatives

Abstract Triazine derivatives are a kind of lubricant additives with excellent tribological properties. It is of great significance to study the quantitative relationship between their chemical structure and tribological properties. In the present study, the quantitative structure tribo-ability relationships (QSTR) between 20 triazine derivatives and their respective extreme-pressure properties as lubricant additives were analyzed by the back propagation neural network (BPNN) method. The BPNN-QSTR model had satisfactory stability and predictive ability (R2 = 0.9965, R2(LOO) = 0.9195, q2 = 0.8274). The anti-wear model also yielded good predictions (R2 = 0.9757, R2(LOO) = 0.6261, q2 = 0.8022). Two- and three-dimensional structural descriptors were used to analyze molecular structures that affected extreme-pressure and anti-wear properties. The results indicate that the three-dimensional molecular dimensions and the bonding modes of the skeleton atoms in the molecules were important factors. In addition, the effects of N, P, O, and other hetero-atoms on the tribological properties were reflected in their corresponding group types and electronic structures.

scholarly journals Nanoparticles of Zn and ZnO as extreme pressure (EP) additives for lubricants

2018 ◽  
Vol 16 (5) ◽  
Author(s):  
Jose Taha Tijerina ◽  
Flavio Castillo ◽  
Javier Leal ◽  
Laura Peña Parás ◽  
Demófilo Maldonado Cortés ◽  
...  
Keyword(s):  
Automotive Industry ◽  
Metal Forming ◽  
Critical Issue ◽  
Measuring System ◽  
Zno Nanoparticle ◽  
Load Carrying Capacity ◽  
Extreme Pressure ◽  
Wear Properties ◽  
Load Carrying ◽  
Nanoparticle Additives

The tribological behavior of moving components and tooling in the automotive industry is a critical issue for improving tool life and increasing efficiency. This work discusses the effects of Zn and ZnO nanoparticle additives homogeneously dispersed within a metal-forming synthetic fluid at various filler fractions: 0.01, 0.05 and 0.10wt.%. Nanolubricants were evaluated under scuffing conditions at extreme pressures (EP) conditions using a four-ball tribotester in order to obtain the load-carrying capacity (poz) behavior, and overall tribological characteristics. This method has shown, with great precision, the influence of the nanofillers on the EP behavior of conventional lubricants. Worn surfaces were characterized through Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) to determine the tribological mechanisms of nanoparticles. An Alicona 3D surface measuring system was used for measuring the surface roughness of the wear scars. Both nanoparticles exhibited better friction-reducing and anti-wear properties compared to the base synthetic fluid. For Zn-based nanolubricants, an enhancement of ~180% in poz was obtained with 0.10wt.%, showing the effect of the spherical nanostructures that were tribosintered onto the surface due to the EPs of the test. Furthermore, the highest enhancement in poz (up to 250%) was achieved with incorporation of 0.10wt.% of ZnO demonstrating the potential of nanolubricants for improving the efficiency of mechanical components.

Avocado oil mixed with an antiwear additive as a potential lubricant – Measurement of antiwear and extreme pressure properties

2020 ◽  
pp. 095440622095123
Author(s):  
Wani Khalid Shafi ◽  
M.S Charoo
Keyword(s):  
Film Formation ◽  
Antiwear Additive ◽  
Protective Film ◽  
Extreme Pressure ◽  
Wear Properties ◽  
Shear Rates ◽  
Avocado Oil ◽  
Maximum Improvement ◽  
Dialkyl Dithiophosphate ◽  
Newtonian Behavior

The paper aims to study the antiwear (AW) and extreme pressure (EP) properties of avocado oil mixed with zinc dialkyl dithiophosphate (ZDDP) in concentrations of 1% to 3% by weight for lubrication purposes. The AW and EP tests are conducted as per ASTM-4172 and ASTM-2783 standards respectively. Further, the rheological behavior of avocado oil mixed with ZDDP is determined for varying shear rates of 50 – 2000 s−1. The maximum improvement in the wear properties for avocado oil is equal to 39.8% at 1 wt.%. The load wear index of pure avocado oil increases from 32.6 to 80.3 at 3 wt.% ZDDP whereas, the weld point increases to 252 kgf at 3 wt.% ZDDP. The improvement in the antiwear and extreme pressure properties are attributed to the protective film formation on the tribopairs as characterized by SEM and EDX analysis. Also, the addition of ZDDP increases the viscosity of the oil at all concentrations and maintains the Newtonian behavior of oil.

Evaluation of tribological characteristics of technical oils with fullerene compositions

2020 ◽  
Vol 98 (4) ◽  
pp. 6-12
Author(s):  
A. Kravtsov ◽  
Keyword(s):  
Experimental Studies ◽  
Fine Powder ◽  
Micelle Formation ◽  
Tribological Characteristics ◽  
Extreme Pressure ◽  
Wear Properties ◽  
High Oleic ◽  
Wear Indicator ◽  
Positive Effect ◽  
Subsequent Addition

The paper presents experimental studies of the tribological characteristics of liquid lubricants of various viscosity classes and various groups of operation when using fullerene compositions. Tribological characteristics were evaluated on a four-ball friction machine according to GOST 9490. The use of fullerene compositions in the form of a finely dispersed fullerene powder, pre-dispersed (dissolved) in vegetable high oleic oils, for example, rapeseed, with the subsequent addition of the resulting composition to technical oils of various viscosity classes and various groups of operation, leads to the following positive effect. The anti-wear properties of oils, which are assessed by the wear indicator, increase by 20,0…30,7 %, and the critical load on 18,8…25,0%. These indicators significantly exceed similar indicators when using fullerene fine powders without preliminary dispersion in vegetable oils, where the effect is on the border 11,1…15 %. Fullerene additives do not affect the extreme pressure properties of base oils, which are assessed by the scuffing load. This result makes it possible to state that the way to improve the tribological properties of lubricants by introducing a fine powder of fullerenes into base technical oils is ineffective. The experimental results obtained confirm the hypothesis about the possibility of the micelle formation mechanism in the lubricant under the action of the electrostatic field of the friction surface. The presence of a surfactant solvent (vegetable oil) allows you to "start" the micelle formation process at lower fullerene concentrations and to obtain the effect of increasing anti-wear properties.

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