scholarly journals Impact of Operating Time on Selected Tribological Properties of the Friction Material in the Brake Pads of Passenger Cars

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 884
Author(s):  
Andrzej Borawski
Keyword(s):  
Tribological Properties ◽  
Operating Time ◽  
Friction Material ◽  
Operating Conditions ◽  
Direct Impact ◽  
Passenger Cars ◽  
Wear Factor ◽  
Brake Pads ◽  
Road Users ◽  
The Coefficient Of Friction

Braking systems have a direct impact on the safety of road users. That is why it is crucial that the performance of brakes be dependable and faultless. Unfortunately, the operating conditions of brakes during their operating time are affected by many variables, which results in changes in their tribological properties. This article presents an attempt to develop a methodology for studying how the operating time affects the value of the coefficient of friction and the abrasive wear factor. The Taguchi method of process optimization was used to plan the experiment, which was based on tests using the ball-cratering method. The results clearly show that the degree of wear affects the properties of the friction material used in the production process of brakes.

scholarly journals Analysis and Comparative Assessment of Basic Tribological Properties of Selected Polymer Composites

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 75 ◽  
Author(s):  
Jerzy Jozwik ◽  
Krzysztof Dziedzic ◽  
Marcin Barszcz ◽  
Mykhaylo Pashechko
Keyword(s):  
Polymer Composites ◽  
Friction Force ◽  
Tribological Properties ◽  
Friction Pair ◽  
Computer Software ◽  
Operating Conditions ◽  
The Coefficient Of Friction ◽  
Cast Polyamide ◽  
Friction Path ◽  
Materials Used

Phenomena occurring in the contact area between two mating bodies are characterised by high complexity and variability. Comparisons are usually made between parameters such as the coefficient of friction, friction force, wear and temperature in relation to time and friction path. Their correct measurement enables the proper evaluation of tribological properties of materials used in the friction pair. This paper concerns the measurements of basic tribological parameters in the friction of selected polymer composites. Knowing the tribological properties of these composite materials, it will be possible to create proper operating conditions for kinematic friction pairs. This study investigated the coefficients of friction, friction force and temperatures of six polymer composites: cast polyamide PA6 G with oil, PA6 G with MoS2, polyoxymethylene POM with aluminium, polyethylene terephthalate PET with polytetrafluoroethylene PTFE, PTFE with bronze, and PTFE with graphite. The friction surface was also examined using an optical system and computer software for 3D measurements. As a result, PA6-G with oil was found to be the best choice as a composite material for thin sliding coatings.

scholarly journals Determination of engine oil change interval for patrol engines based on actual operating time

2021 ◽  
Vol 18 (3) ◽  
pp. 274-285
Author(s):  
A. A. Abakarov ◽  
Sh. M. Igitov ◽  
Ali A. Abakarov
Keyword(s):  
Operating Time ◽  
Chemical Properties ◽  
The United States ◽  
Climatic Conditions ◽  
Operating Conditions ◽  
Engine Oil ◽  
Rolling Stock ◽  
Passenger Cars ◽  
Gasoline Engines ◽  
On The Road

Introduction. This paper shows the results of a study of the frequency of maintenance of passenger cars in various operating conditions, and provides recommendations for replacing the engine oil of gasoline engines (category SN classification according to API) according to the actual engine operating time (moto-hours). The service book of passenger cars contains the regulations for car maintenance with a list of operations that must be performed. The oil change intervals specified in the Regulations on Maintenance and Repair of Rolling Stock of motor Transport and the factory instructions do not take into account the specifics of the operation of vehicles. Depending on the road and climatic conditions and the operating mode, the standard maintenance schedule can be adjusted, in particular, the frequency of engine oil changes. The scientific novelty of the work is to determine the intervals of car maintenance for specific operating conditions.Materials and methods. The paper presents an analysis of Russian and foreign car maintenance systems, in particular, the oil change intervals of gasoline engines in European countries, the United States and Japan.The results of operational and resource tests of motor oils of gasoline engines carried out by methods of measuring their physical and chemical properties are presented.Results. In this paper, based on the analysis of the problem, recommendations for changing oil in gasoline engines by motorcycle hours for the conditions of the Republic of Dagestan (RD) are developed.The use of external and built-in technical means for calculating the motor hours allows you to determine the recommended oil change interval.Discussion and conclusion. In this paper, on the basis of research on a certain number of vehicles operating in various (including difficult) conditions, recommendations are developed that allow you to determine the rules of car maintenance for various operating conditions.

scholarly journals Suggested Research Method for Testing Selected Tribological Properties of Friction Components in Vehicle Braking Systems

2016 ◽  
Vol 10 (3) ◽  
pp. 223-226 ◽  
Author(s):  
Andrzej Borawski
Keyword(s):  
Process Optimization ◽  
Coefficient Of Friction ◽  
Tribological Properties ◽  
Research Method ◽  
Taguchi’S Method ◽  
Braking System ◽  
Heating And Cooling ◽  
Road Users ◽  
The People ◽  
The Coefficient Of Friction

Abstract The braking system is one of the most important systems in any vehicle. Its proper functioning may determine the health and life the people inside the vehicle as well as other road users. Therefore, it is important that the parameters which characterise the functioning of brakes changed as little as possible throughout their lifespan. Multiple instances of heating and cooling of the working components of the brake system as well as the environment they work in may impact their tribological properties. This article describes a method of evaluating the coefficient of friction and the wear speed of abrasive wear of friction working components of brakes. The methodology was developed on the basis of Taguchi’s method of process optimization.

Influence of carbon nanotubes on the properties of friction composite materials

2019 ◽  
Vol 54 (16) ◽  
pp. 2101-2111
Author(s):  
Emad F EL-kashif ◽  
Shaimaa A Esmail ◽  
Omayma AM Elkady ◽  
BS Azzam ◽  
Ali A Khattab
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Friction Coefficient ◽  
Tribological Properties ◽  
Smart Materials ◽  
Arc Discharge ◽  
Weight Ratio ◽  
Friction Material ◽  
Operating Conditions ◽  
Friction Materials

Carbon nanotubes have a lot of applications in mechanical fields. This is because nanomaterials have many superior mechanical properties such as very high strength-to-weight ratio, high modulus-to-weight ratio, high corrosion resistance, and super intelligence properties, which make them as smart materials. One of these attractive applications is the use of carbon nanotubes in vehicle brake friction material. Therefore, the fabrication and testing processes of these nanomaterials should be performed carefully to evaluate their mechanical, tribological, and noise properties. In this paper, friction material mixed with carbon nanotubes have been fabricated with different carbon nanotube contents and the same fabrication parameters. The carbon nanotubes have been produced using the conventional submerged arc discharge technique. The produced friction materials have been cut into pieces with standard sizes and then tested mechanically and tribologically. The results of tests have illustrated that the addition of carbon nanotubes into the friction materials could improve their mechanical properties (hardness, strength, and modulus) and also could enhance their tribological properties (wear rate and friction coefficient). Moreover, the tests showed that the presence of carbon nanotubes in friction materials could reduce the noise, vibration of the friction materials, and reduce the temperature rise due to the effect of friction, which means that the carbon nanotubes could raise the thermal conductivity of friction material, while the friction coefficient has stayed within the allowable standard limits (0.35–0.45). Surface morphology shows that the presence of carbon nanotubes in the friction materials could help to avoid surface friction cracks or fins within the normal operating conditions. The good combination of mechanical and tribological properties was obtained at 0.5% carbon nanotubes.

scholarly journals Common Methods in Analysing the Tribological Properties of Brake Pads and Discs – A Review

2019 ◽  
Vol 13 (3) ◽  
pp. 189-199 ◽  
Author(s):  
Andrzej Borawski
Keyword(s):  
Tribological Properties ◽  
New Products ◽  
Dry Sliding ◽  
Passenger Cars ◽  
Friction Materials ◽  
Brake Pads ◽  
Safety Concerns ◽  
Operational Quality ◽  
Disc Brakes

Abstract Disc brakes in passenger cars are extremely important due to safety concerns. Their operational quality largely rests on the conditions of contact between the working elements, which mainly consists offlat and dry sliding. The tribological phenomena thatoccur during braking are, unfortunately, extremely complex and difficult to recreate in laboratory settings. Many scientific institutes conduct research to improve our understanding of these phenomena. The results they present make it possible to continuously simplify the procedures for selecting friction materials and reducing the costs of identifying the properties of new products. This article analyses the methods commonly used by researchers. It also presents different set-ups of research stations, as well as the advantages and drawbacks of each method.

scholarly journals Functionalization of alumina particles to improve the performance of eco-friendly brake-pads

Friction ◽  
2021 ◽  
Author(s):  
Vanvirsinh Chauhan ◽  
Jayashree Bijwe ◽  
Ashish Darpe
Keyword(s):  
Friction And Wear ◽  
Friction Material ◽  
Abrasive Particles ◽  
Inorganic Particles ◽  
X Ray ◽  
Brake Pads ◽  
Matrix Adhesion ◽  
Alumina Particles ◽  
The Coefficient Of Friction ◽  
Resin Binder

AbstractAbrasives, such as oxides of alumina (Al), silica (Si), zirconia (Zr), chromium (Cr) etc., are added to raise the friction level and also to remove the glaze on the disc so that surface will be rejuvenated continuously during braking and will contribute to maintain the desired friction level. However, these inorganic particles have less adhesion with the resin/binder and hence are easily dug out during wearing process contributing to higher wear. If efforts are made to enhance the filler-matrix adhesion, not only the wear of friction material (FM) should reduce, the particles may stay for a longer time on the tribo-surface of the pads to contribute fully towards controlling the coefficient of friction (μ). In the present study, alumina particles were selected for siloxane treatment to improve the filler-matrix adhesion. Two types of eco-friendly (free from asbestos and Cu) brake-pads were developed using alumina as a theme ingredient (treated and untreated) keeping all the parent formulation identical. An additional type of brake-pads without alumina particles was also developed to observe the effect of abrasive particles on the tribo-performance. The performance properties (physical, mechanical, and tribological) of brake-pads were compared when evaluated in identical conditions. The tribo-testing was done on full-scale brake inertia dynamometer following the procedure in Japanese automobile standard (JASO C 406). It was observed that siloxane treatment affected both friction and wear of brake-pads in a beneficial way. Wear resistance got increased 35% for siloxane treated pads. Worn surfaces were analysed using scanning electron microscopy (SEM) and energy dispersive X-ray (EDAX) technique.

THE INFLUENCE OF THE SURFACE LAYER STRUCTURE IN DISC BRAKE PADS ON THEIR TRIBOLOGICAL PROPERTIES

Tribologia ◽  
2016 ◽  
Vol 267 (3) ◽  
pp. 71-85
Author(s):  
Andrzej GAJEK ◽  
Wojciech SZCZYPIŃSKI-SALA
Keyword(s):  
Friction Surface ◽  
Chemical Elements ◽  
Layer Structure ◽  
Friction Material ◽  
Compact Structure ◽  
Friction Layer ◽  
Brake Pads ◽  
Disc Brakes ◽  
The Coefficient Of Friction ◽  
Point Line

The article presents the results of the stand tribological investigation and microscopic observations of brake pad materials for automotive disc brakes. The reasons for the scatter of the friction coefficient value are analysed. The results of the brake pads’ friction surface topography observations and chemical constitution are presented. The investigations were carried out with scanning electron microscopy SEM and energy dispersive X-ray spectroscopy EDS. The point, line, and surface analysis of friction layer were done. The average contents of the chemical elements on the friction surface are presented. The heterogeneous nature of the structure on the friction layer was observed. The analysis has shown that brake pads with a compact structure of friction layer and large quantity components (10 components with more than 1% content each) had a smaller scatter of the coefficient of friction value in relation to the materials with a loose structure and less quantity components. The next part of the article presents the structure and geometric parameter products of the wear of the friction material. The problem concerning the quantity limitation of the wear particles entering the environment as dust was discussed.

scholarly journals Mechanical and the effect of oil absorption on tribological properties of carbon-based brake pad material

2021 ◽  
Vol 38 (1−2) ◽  
Author(s):  
Oluwatoyin Joseph Gbadeyan ◽  
T. P. Mohan ◽  
K. Kanny
Keyword(s):  
Tribological Properties ◽  
Absorption Rate ◽  
Friction Material ◽  
Material System ◽  
Oil Absorption ◽  
Brake Pad ◽  
Wear Properties ◽  
Absorption Properties ◽  
Brake Pads ◽  
Carbon Based

This research focuses on the mechanical and effect of oil absorption on the tribological properties of carbon-based brake pad material (CBP).  Carbon-based materials, including those at a nanosize, are combined for developed brake pad material. The mechanical properties related to wear properties such as compression strength, stiffness, hardness, and absorption properties were determined. The effect of oil absorption on the tribological properties of carbon-based materials was investigated. The obtained properties are compared with that of a ceramic-made brake pad (commercial). The experimental results show that the mechanical and absorption properties of the developed brake pad material varied with the combination and quantity of additives used to develop each brake pad material. CBP material offered higher performance than ceramic-made brake pads. The CBP material showed a higher shear strength of about 110%, 51% enhanced compressive strength, 35% greater modulus, comparative statistical hardness, 98% lesser water intake, and 97% oil absorption rate than ceramic made brake pad. The tribological properties of friction material after soaked in oil proved that absorption properties affect tribological properties of brake pads, which can be attributed to the oil content in the material system. The effect of oil uptakes on wear rate and friction of the commercial brake pad was higher than CBP materials, implying that the loading of carbon-based materials is a viable way to reduce absorption rate, which helps in increasing brake pad performance. The improved properties are suggestive of materials combinations that may be used to develop brake pad materials.

Optimization of Mixing Conditions on the Physical and Tribological Properties of Brake Pads

2019 ◽  
Vol 824 ◽  
pp. 67-72
Author(s):  
Kasidet Rupiyawet ◽  
Kritsana Kaewlob ◽  
Pornapa Sujaridworakun ◽  
Wantanee Buggakupta
Keyword(s):  
Specific Gravity ◽  
Tribological Properties ◽  
Raw Materials ◽  
Friction Material ◽  
Mixing Conditions ◽  
Mixing Condition ◽  
Brake Pads ◽  
Wear And Friction ◽  
Density Values ◽  
Automotive Brake

This study investigates the effects of mixing condition on hardness, porosity, specific gravity, wear, and friction characteristics of automotive brake materials. In the experiment, mixing raw materials with three different conditions of impeller speed (3000, 4500, and 6000 rpm), mixing duration (up to 8 min) and mixture loading based on a mixer volume (35, 50 and 65 vol% ) were determined using the formulated mixture composition. Homogeneity in terms of density values including hardness, porosity, and specific gravity of the finished brake pads were determined. The surfaces and the distribution of friction material were studied using scanning electron microscopy (SEM). The correlation between various mixing conditions and physical and tribological properties of brake pads were discussed and reported.

Dry Sliding Wear Studies of Cu-Based Powder Metallurgy Brake Materials

2012 ◽  
Author(s):  
Glenn K. Gyimah ◽  
Dong Chen ◽  
Ping Huang
Keyword(s):  
Sliding Wear ◽  
Wear Behavior ◽  
Friction Material ◽  
Dry Sliding Wear ◽  
Temperature Sensitive ◽  
Brake Pads ◽  
Different Temperatures ◽  
The Coefficient Of Friction ◽  
Materials Used ◽  
Mechanical And Tribological Characteristics

A novel friction material based on Cu-based powder with several additional elements, such as Al, SiO2, Fe, graphite, Sn, Mn and MoS2, has been developed by PM techniques in order to study the wear to improve mechanical and tribological characteristics of train brake pads. The materials used were sintered at three different temperatures (850°C, 900°C and 950°C). A high pressure pad-on-disc braking tester was developed to test the wear behavior of these materials without lubrication. Wear was measured by microscopic examination of the pad after the tribometer test. The tests showed that the coefficient of friction (COF), wear rate and wear number were improved immensely by high temperature sintering. This shows that the sintering temperature level plays an important role in the performance of the braking material. In addition, the tribological and the mechanical properties were found to be temperature sensitive.

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