Insight into friction and lubrication performances of surface-textured cylinder liners and piston rings

2021 ◽  
pp. 146808742110502
Author(s):  
Kai Ma ◽  
Zhiwei Guo ◽  
Chengqing Yuan
Keyword(s):  
Surface Morphology ◽  
Contact Resistance ◽  
Surface Texture ◽  
Friction And Wear ◽  
Lubrication Mechanism ◽  
Piston Rings ◽  
Oil Storage ◽  
Cavitation Effect ◽  
Different Temperatures ◽  
Friction And Lubrication

The effects of surface-texture technology on the friction and lubrication mechanism of cylinder liner-piston rings (CLPR) were explored in this study. An inclined groove texture was machined on the CL of a S195 diesel engine and dimples designed on the gas ring. Friction and wear tests of nontextured (NT), CL textured (CLT), and PR textured (PRT) conditions were performed on a CLTR friction and wear tester under different temperatures. First, the characteristics of friction and lubrication at different temperatures were analyzed by examining friction and contact resistance. Then, the wear characteristics were analyzed by examining surface morphology parameters of the CL and the PR wear mass after testing. Finally, the friction and lubrication mechanisms of NT, CLT, and PRT were studied by analyses of real-time friction and contact resistance in one cycle. The results showed that, under the same temperature, CLT and PRT increased oil film thickness, improved the lubrication state, and reduced friction, with CLT better than PRT in these respects. With increased temperature, the wear degree of CL liners became larger. The existence of surface texture reduced CL wear, yielded CL surface morphology not excessively changed by temperature, and improved its supporting performance and oil storage capacity. The inlet suction effect, structural effect, micro-wedge action, balancing wedge action, squeezing effect, and cavitation effect should be taken into account together when exploring the mechanism of the influence of surface texture on friction pairs. This study provided a method for scholars to explore the friction and lubrication mechanism of different texture types and provided an experimental basis for improving the performance of CLPR friction pairs.

Oil-soluble ionic liquid to lubricate silicon

2021 ◽  
pp. 135065012098488
Author(s):  
Waleed Al-Sallami ◽  
Pourya Parsaeian ◽  
Abdel Dorgham ◽  
Anne Neville
Keyword(s):  
Ionic Liquid ◽  
High Temperature ◽  
Friction And Wear ◽  
Tribological Performance ◽  
Considerable Reduction ◽  
Zinc Dialkyldithiophosphate ◽  
Lubrication Mechanism ◽  
Wear Coefficient ◽  
Wear Performance ◽  
Micro Scale

Trihexyltetradecylphosphonium bis(2-ethylhexyl)phosphate (phosphonium phosphate) ionic liquid is soluble in non-polar lubricants. It has been proposed as an effective anti-wear additive comparable to zinc dialkyldithiophosphate. Previously, phosphonium phosphate has shown a better anti-wear performance under some conditions such as high temperature. In this work, the tribological performance and the lubrication mechanism of phosphonium phosphate are compared with that of zinc dialkyldithiophosphate when lubricating silicon under various tribological conditions. This can lead to an understanding of the reasons behind the superior anti-wear performance of phosphonium phosphate under some conditions. A micro-scale study is conducted using a nanotribometer. The results show that both additives lead to a considerable reduction in both friction and wear coefficients. The reduction in the wear coefficient is mainly controlled by the formation of the tribofilm on the rubbing surfaces. Zinc dialkyldithiophosphate can create a thicker tribofilm, which results in a better anti-wear performance. However, the formation of a thicker film will lead to a faster depletion and thus phosphonium phosphate can provide better anti-wear performance when the depletion of zinc dialkyldithiophosphate starts.

Preparation and tribological properties of a microemulsion for magnesium alloy warm rolling

2019 ◽  
Vol 71 (1) ◽  
pp. 74-82 ◽  
Author(s):  
Chang Dong ◽  
Jianlin Sun ◽  
Zixuan Cheng ◽  
Yuqing Hou
Keyword(s):  
Magnesium Alloy ◽  
Surface Morphology ◽  
Tribological Properties ◽  
Warm Rolling ◽  
Friction Reduction ◽  
Alloy Strip ◽  
Lubrication Mechanism ◽  
Content Type ◽  
Rolling Oil ◽  
Lubrication Properties

Purpose The purpose of this paper is to synthesize a microemulsion and investigate its tribological properties as lubricant. Magnesium alloy warm rolling experiments were conducted. Surface morphology was observed and wear form was summarized. The composition of surface residues was analyzed, which sheds light on the lubrication mechanism of microemulsion. Design/methodology/approach A microemulsion was prepared with a proper amount of oil, surfactant, cosurfactant, water and other additives for magnesium alloy strip warm rolling. Tribological properties, such as maximum non-seizure load (PB), friction coefficient (μ) and wear scar diameter (D) of the microemulsion were measured and compared with those of emulsion and rolling oil on an MR-10A four-ball tribotester. The extreme pressure anti-wear coefficients (O) were calculated and compared. Warm rolling experiments were carried out on a Ф 170/400 × 300 mm four-high rolling mill at 240°C to compare the finish rolling thickness and surface quality of rolled AZ31B magnesium alloy strip under four lubrication states, namely, no lubrication, rolling oil, microemulsion and emulsion. The surface morphology after warm rolling was observed with confocal laser scanning microscope and scanning electron microscope, respectively. The composition of surface residues was analyzed with energy dispersive spectrometry and X-Ray photoelectron spectroscopy. Findings Surface morphology indicated that pitting wear, adhesive wear and ploughing wear were three main forms of wear in magnesium alloy warm rolling. Microemulsion had excellent lubrication properties with less residual oil remaining. Two types of adsorption layers formed on magnesium alloy strip surface were responsible for lubrication properties. MgSO4 and magnesium stearate in the reaction layer played a key role in anti-wear and friction-reduction in warm rolling. Originality/value The study is original and gives valuable information on lubrication mechanism of microemulsion in warm rolling of magnesium alloy strips.

The Role of Bionic Modifications in Reducing Adhesion and Draft of Agricultural and Earthmoving Machinery

2013 ◽  
Vol 461 ◽  
pp. 553-561
Author(s):  
Rashid Qaisrani ◽  
Jian Qiao Li ◽  
Mohammad Iqbal
Keyword(s):  
Energy Consumption ◽  
Surface Morphology ◽  
Construction Materials ◽  
Force Analysis ◽  
Lubrication Mechanism ◽  
Limited Application ◽  
Practical Field ◽  
Adhesion Friction

Soil adheres to the surfaces of soil engaging components of earthmoving machinery and equipment. It has been pbserved that up to 50% of energy may be consumed in overcoming adhesion and friction of soil to the surfaces of soil engaging components of agricultural and earthmoving machinery. Surface morphology, chemical composition, elasticity, lubrication mechanism and electric osmosis play significant roles in reducing adhesion, friction and energy consumption of various equipment. Some of these techniques have very limited application in the practical field conditions because of the time and amount of fluid required to achieve the desired results. Whereas other techniques are effective in reducing adhesion and friction and improving work quality of these machines and equipment. This paper analyses the forces including the drafts of conventional and bionic bulldozing blades operating under identical conditions using mathematical modelling. The force analysis showed that both adhesion and friction play major role in reducing drafts of earrthmoving machinery. It is also worth stating that both the surface morphology and the construction materials play important role in reducing adhesion and friction of ground eganging components of earthmoving machinery.

Wear Properties and Scuffing Resistance of the Cr–Al2O3 Coated Piston Rings: The Effect of Convexity Position on Barrel Surface

2018 ◽  
Vol 141 (2) ◽  
Author(s):  
Siqi Ma ◽  
Wenbin Chen ◽  
Chengdi Li ◽  
Mei Jin ◽  
Ruoxuan Huang ◽  
...  
Keyword(s):  
Cast Iron ◽  
Friction Coefficient ◽  
Surface Morphology ◽  
Pressure Distribution ◽  
Cylinder Liner ◽  
Wear Loss ◽  
Wear Properties ◽  
Piston Rings ◽  
Oil Film ◽  
Influencing Mechanism

This work investigates the effect of convexity position of ring barrel surface on the wear properties and scuffing resistance of the Cr–Al2O3 coated piston rings against with the CuNiCr cast iron cylinder liner. The scuffed surface morphology and elements distribution as well as the oil film edge were analyzed to explore the influencing mechanism of the convexity position on the scuffing resistance. The results show that the convexity offset rate on the barrel surface of the ring has no noticeable influence on both friction coefficient and wear loss near the dead points, but a suitable convexity position will result in the improved scuffing resistance. The shape of the barrel face not only affects the worn area on the ring, but also determines the oil film wedge and pressure distribution, consequently influences the scuffing resistance.

A Review of Surface Texture of Tribological Interfaces

2010 ◽  
Vol 37-38 ◽  
pp. 41-45 ◽  
Author(s):  
Zhi Wei Wang ◽  
Mei Wei Chen ◽  
Jian Wei Wu ◽  
Hai Hui Zheng ◽  
Xiao Feng Zheng
Keyword(s):  
Modeling And Simulation ◽  
Surface Texture ◽  
Review Paper ◽  
Tribological Performance ◽  
Current Status ◽  
Comprehensive View ◽  
Lubrication Performance ◽  
Mechanical Components ◽  
Friction And Lubrication

Surface texture of tribological interfaces has the potential to improve friction and lubrication performance of various mechanical components. This review paper emphasizes on the current status of the research of surface texture, including the features, the effects on tribological performance, the forming techniques, and the modeling and simulation of surface texture. It is intended to help readers to gain a more comprehensive view on surface texture of tribological interfaces.

scholarly journals Measurement of the Thermophysical Properties of Anisotropic Insulation Materials with Consideration of the Effect of Thermal Contact Resistance

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1353 ◽  
Author(s):  
Dongxu Han ◽  
Kai Yue ◽  
Liang Cheng ◽  
Xuri Yang ◽  
Xinxin Zhang
Keyword(s):  
Thermal Conductivity ◽  
Thermal Resistance ◽  
Contact Resistance ◽  
Thermal Contact Resistance ◽  
Thermal Contact ◽  
Thermal Contact Conductance ◽  
Maximum Deviation ◽  
Insulation Materials ◽  
Steady State Method ◽  
Different Temperatures

A novel method involving the effect of thermal contact resistance (TCR) was proposed using a plane heat source smaller than the measured samples for improving measurement accuracy of the simultaneous determination of in-plane and cross-plane thermal conductivities and the volumetric heat capacity of anisotropic materials. The heat transfer during the measurement process was mathematically modeled in a 3D Cartesian coordinate system. The temperature distribution inside the sample was analytically derived by applying Laplace transform and the variables separation method. A multiparameter estimation algorithm was developed on the basis of the sensitivity analysis of the parameters to simultaneously estimate the measured parameters. The correctness of the algorithm was verified by performing simulation experiments. The thermophysical parameters of insulating materials were experimentally measured using the proposed method at different temperatures and pressures. Fiber glass and ceramic insulation materials were tested at room temperature. The measured results showed that the relative error was 1.6% less than the standard value and proved the accuracy of the proposed method. The TCRs measured at different pressures were compared with those obtained using the steady-state method, and the maximum deviation was 8.5%. The thermal conductivity obtained with the contact thermal resistance was smaller than that without the thermal resistance. The measurement results for the anisotropic silica aerogels at different temperatures and pressures revealed that the thermal conductivity and thermal contact conductance increased as temperature and pressure increased.

Sign in / Sign up

Export Citation Format

Share Document