Features of sliding friction process in pair «steel R6M5—steel 45» when using Litol-24 lubricant modified with MoS2 particles

Using LAMMPS to establish the three-dimensional sliding friction model of the nanoscale diamond hemisphere with the single-crystal copper surface. Simulation and solving the process of sliding friction, research the micro-contact area atomic states change in sliding friction process, and study the friction characteristics change when the rigid sphere sliding on rough surface of the single crystal copper with minute projections. The results indicate that, in the sliding friction process, the lattice of substrate atoms are damaged under the forces of the extrusion which also cause corresponding dislocation and deformation. In the direction of the hemisphere movement, generate the pileup and side stream phenomena, and produce furrows. Friction and normal force rapidly increase with the depth of contact, and then enter into a stable sliding phase. For the thermal motion of atoms, formation of dislocations and the stick-slip effect, the curves of friction and normal force present waves of sawtooth. Small defect on surface of the substrate almost have no effect on the process of sliding friction.

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Simulations on Sliding Process between Si-DLC and DLC Films on a Water-Lubricated Condition

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.29-32.1408 ◽

2010 ◽

Vol 29-32 ◽

pp. 1408-1413 ◽

Cited By ~ 1

Author(s):

Hui Qing Lan ◽

Can Liu ◽

Takahisa Kato

Keyword(s):

Sliding Friction ◽

Md Simulations ◽

Low Friction ◽

Wear Performance ◽

Friction Process ◽

The Past ◽

Significant Interest ◽

Lubrication Layer ◽

Higher Temperature ◽

Silicon Doped

Diamond like carbon (DLC) films have been extensively studied over the past decades due to their unique combination of properties, in particular, silicon-doped DLC (Si-DLC) films are of significant interest for tribological effects, they had a very low friction coefficient and possess the potential to improve wear performance in humid atmospheres and at higher temperature. But many experimental results of the Si-DLC films showed that their tribological properties changed greatly on different silicon contents. In the paper, molecular dynamics (MD) simulations were used to study a sliding friction process between Si-DLC and DLC films on an un-lubricated and a water-lubricated condition respectively. The results have been shown that a transfer film between the Si-DLC and DLC films was formed on the un-lubricated condition. In contrast, a boundary lubrication layer was found on the water-lubricated condition. Moreover, the friction force on the un-lubricated condition was larger than those on the water-lubricated condition.

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Adequate Force Characteristics of a Friction System

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.13.20 ◽

2013 ◽

Vol 13 ◽

pp. 20-36

Author(s):

Zdzisław Pluta ◽

Tadeusz Hryniewicz

Keyword(s):

Sliding Friction ◽

Static Friction ◽

The Body ◽

Friction Process ◽

New Knowledge ◽

Mechanical Behaviours ◽

Adequate Definition ◽

Definition Of ◽

Inertia Forces ◽

Force Characteristics

In the paper, at first some remarks concerning friction are presented by the definition of the friction itself, as well as its essential force characteristics. An adequate definition of friction is introduced, and moreover a correct its characteristics. Next the statics, dynamics, and kinematics of the friction system is given, forming the force characteristics of this system for each of the mechanical behaviours, taking into account real inertia forces of the body under friction. Three types of coefficients of sliding friction have been separated, namely: coefficient of static friction, dynamic friction, and kinematic friction. Then the comparative analysis of existent and new knowledge on the force characteristics of friction process has been presented. The consideration on how to determine the coefficient of static friction has also been carried out. Reflections on the possibilities to form further force characteristics of the friction process are presented to develop this work with some final remarks directing the attention on the conditions of development of science on friction.

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DESCRIPTIVE MODEL OF SLIDING FRICTION PROCESSES

Environment Technology Resources Proceedings of the International Scientific and Practical Conference ◽

10.17770/etr2009vol2.1028 ◽

2015 ◽

Vol 2 ◽

pp. 227

Author(s):

Andris Martinovs ◽

Vladimir Gonca

Keyword(s):

Friction Coefficient ◽

Surface Area ◽

Contact Surface ◽

Sliding Friction ◽

Friction Model ◽

Friction Process ◽

Contact Surface Area ◽

Optimal Surface ◽

Sliding Friction Coefficient ◽

The Mathematical Model

Paper analyses the sliding friction coefficient of rubber on concrete, timber and ceramic tile surfaces depending on the weight of the sliding object and contact surface area. It has been established that increase in the weight of the object makes sliding friction coefficient to grow. In the case of increase in size of contact area, sliding friction coefficient between rubber and concrete also increases, but it decreases between rubber- timber and rubber- tile. The mathematical model for description of sliding friction process has been developed which can be used to determine optimal surface area and a pattern as well as optimal weight of the sliding object in order to provide sufficient sliding friction. Model has five independent constants. It includes the contact surface area, the weight and the velocity of the sliding object, sliding friction coefficient, temperature and time.

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Dry Sliding Friction of Tool Steels and Their Comparison of Wear in Contact with ZrO2 and X46Cr13

Materials ◽

10.3390/ma13102359 ◽

2020 ◽

Vol 13 (10) ◽

pp. 2359

Author(s):

Michal Krbata ◽

Maros Eckert ◽

Lenka Bartosova ◽

Igor Barenyi ◽

Jozef Majerik ◽

...

Keyword(s):

Sliding Friction ◽

Process Analysis ◽

Cutting Tools ◽

High Strength Steels ◽

High Strength ◽

Sample Surface ◽

Tool Steels ◽

Friction Process ◽

Working Cycle ◽

The Impact

Tool steels are used in stamping, shearing processes, and as cutting tools due to their good mechanical properties. During their working cycle, steels are subject to aggressive conditions such as heat stress, fatigue, and wear. In this paper, three tool steels, namely X153CrMoV12, X37CrMoV5-1, and X45NiCrMo4 were selected against two types of bearing balls, ZrO2 and X46Cr1. All measurements were performed on a UMT TriboLab universal tribometric instrument under dry conditions. The main objective of the experiment was to analyze and compare tool steel wear in contact with two kinds of bearing balls with a diameter of 4.76 mm. This evaluation is focused on the hardness, surface roughness, and microstructure of all samples and on the impact of the input parameters on the resulting wear. All three types of tool steels were measured in the basic annealed state and, subsequently, in the state after hardening and tempering. Experimental results show that tool steels, belonging to high strength steels, can successfully represent wear resistant steels. The content of carbide elements, their size, and shape in the microstructure play an important role in the friction process and subsequent wear. Three types of loads were used and compared in the experiments 30, 60, and 90 N. Increasing the load results in significant degradation of the material on the sample surface. Lastly, the impact of hardness and roughness of materials on wear has also been proven. If abrasive wear occurs in the friction process, there is a greater degree of wear than that of adhesive wear. This is due to less abrasive particles, which behave like a cutting wedge and are subject to subsequent deformation strengthening due to the load increase, which adversely affects the further friction process. Analysis of the results showed that the ZrO2 ceramic ball showed significantly better wear values when compared to the X46Cr13 stainless steel ball. It also improves the values of the coefficient of friction with respect to the type of wear that occurs when the experimental materials and counterparts are in contact.

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Molecular dynamic simulations of the roles of nanoparticles in sliding friction process

Chemical Physics Letters ◽

10.1016/j.cplett.2019.04.076 ◽

2019 ◽

Vol 728 ◽

pp. 44-49 ◽

Cited By ~ 2

Author(s):

Chunhui Ji ◽

Shuangqiu Sun ◽

Bing Wang ◽

Bin Lin

Keyword(s):

Molecular Dynamic ◽

Sliding Friction ◽

Molecular Dynamic Simulations ◽

Dynamic Simulations ◽

Friction Process

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A Recursive Characteristics Analysis-Based Stationarity Evaluation Model for Friction-Induced Attractors in the Sliding Friction Process

Journal of Tribology ◽

10.1115/1.4050425 ◽

2021 ◽

Vol 143 (10) ◽

Author(s):

Guodong Sun ◽

Ying Zhang ◽

Chao Zhang ◽

Shihui Lang ◽

Hua Zhu

Keyword(s):

Sliding Friction ◽

Evaluation Model ◽

Normal Pressure ◽

Recurrence Quantification Analysis ◽

Friction Process ◽

Recurrence Quantification ◽

Characteristics Analysis ◽

The Coefficient Of Friction ◽

Quantification Analysis ◽

Scalar Time Series

Abstract In this study, the coefficient of friction (COF) signals throughout the running-in process were examined by sliding a ring against a static disc. By reconstructing the scalar time-series into multi-dimensional phase spaces, friction-induced attractors were obtained and quantified by recursive characteristics analysis, which can effectively realize the running-in status identification. Moreover, a recursive characteristics analysis-based evaluation model was established to investigate the stationarity of the friction-induced attractors based on the recurrence quantification analysis (RQA) measures. The analyses of the numerically simulated signals and experimental results indicate that the extracted model is an intuitive and effective method. Furthermore, to improve the stationary of the friction-induced attractors, the normal pressure should be low, whereas the relative sliding velocities should be increased appropriately. These results would contribute to the revelation of the recursive characteristics of the tribosystem and the improvement of the stationarity of friction-induced attractors.

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Analytical model and experimental validation of the local damage mechanism of solid lubricant films for metal matrix self-lubricating composites

RSC Advances ◽

10.1039/c5ra14224e ◽

2015 ◽

Vol 5 (91) ◽

pp. 74850-74857 ◽

Cited By ~ 9

Author(s):

Zengshi Xu ◽

Qiaoxin Zhang ◽

Wenzheng Zhai ◽

Xixing Li

Keyword(s):

Metal Matrix ◽

Experimental Validation ◽

Solid Lubricant ◽

Sliding Friction ◽

Damage Mechanism ◽

Local Damage ◽

Friction Process ◽

Lubricant Films ◽

Solid Lubricant Films ◽

Self Lubricating Composites

Schematic representation of the local damage mechanism of solid lubricant films during the sliding friction process.

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Impact of Electronic Radiation on the Morphology of the Fine Structure of the Surface Layer of R6M5 Steel

Machines ◽

10.3390/machines9020024 ◽

2021 ◽

Vol 9 (2) ◽

pp. 24

Author(s):

Bauyrzhan Rakhadilov ◽

Aidar Kengesbekov ◽

Laila Zhurerova ◽

Rauan Kozhanova ◽

Zhuldyz Sagdoldina

Keyword(s):

Surface Layer ◽

Electron Beam ◽

Fine Structure ◽

Electron Irradiation ◽

High Speed ◽

High Speed Steel ◽

Internal Stresses ◽

Steel R6m5 ◽

R6m5 Steel ◽

Initial State

In recent decades, great efforts have been made to significantly improve the performance characteristics of high-speed steel using various surface hardening techniques. Electron beam modification is engaging because it has an exceptionally high thermal efficiency and can significantly improve steels’ physical and mechanical properties. This work is devoted to researching the fine structure and changing the structural phase state of the surface layer of R6M5 high-speed steel after exposure to an electron beam. Electron beam treatment of steel R6M5 was carried out on a vacuum installation. The structure and phase composition of P6M5 steel samples were studied by transmission electron microscopy. Determined that after electron irradiation, the steel structure as in the initial state consists of martensite, carbides and residual austenite. After electron irradiation, an increase in the volume fraction of lamellar martensite is observed: the fraction of lamellar martensite in the initial state is 80%, and after irradiation, it is ~90% of the total fraction of α′-martensite. The action of the electron beam led to an increase in internal stresses in α′-martensite. Revealed, the value of the scalar dislocation density in R6M5 steel after exposure to an electron beam is higher than in the initial state. A cardinal difference in the state of the material after exposure to an electron beam is the presence of bending extinction contours in all M6C carbide particles.

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