Brake Pad Samples Research Articles

Effect of Kenaf Core Fibre (Hibiscus cannabinus) as one of the Dispersing Phases in Brake Pad Composite Production

Brakes are essential parts of all means of transportation. Their function is to slow or stop a vehicle by friction. Asbestos has been widely used in the production of brake pads. However, its application poses adverse effects on human health and the environment. The aim of this study was to determine the effect of kenaf core fibers as one of the dispersing phases in brake pad composite production. The materials and methods employed in the study, followed procedures in established standards and literatures. The materials were grounded into fine powder and sieved into grade sizes of 100 µm and 200 µm. They were weighed on a digital scale according to a specified composition and mixed thoroughly for about five (5) minutes to obtain homogeneity of the mixture. Afterwards, the mixed compositions were placed inside a 5 cm × 3 cm × 2 cm cylindrical mould. These mixtures were then compacted on a hydraulic press and allowed to dry at an ambient temperature of 37°C. A series of physio-mechanical tests such as porosity, ash content, density, compressive strength, hardness and wear rate were conducted on the developed brake pad samples as well as the control samples. The results showed that the average values for porosity, ash content and density of the developed samples enhanced with kenaf core fibres were 0.813%, 57.25% and 1.389 kg/m3 respectively. These values compare well with that of the control samples. Also, the hardness, wear rate and compressive strength of the samples enhanced with kenaf fibers gave average values of 121.25 BHN, 10.121×10-2 g/km and 105.75 MPa respectively. These values also compare well with that of the control samples. From the results gotten and all the properties determined, the study showed that kenaf core fibres has good potentials as dispersing phases for brake pad composite production.

Influence of lignocellulosic banana fiber on the thermal stability of brake pad material

In automobiles, the braking system is foremost amongst the most imperative safety features. The basic principle of the braking system is to provide frictional resistance to a moving machine. During brake application, frictional heat is generated, which can cause numerous adverse effects on the brake assembly such as brake fade and wear. Binder is one of the crucial element among all the elements of a brake pad because it maintains the structural integrity of the pads. At high temperature, the binder decomposes due to its poor thermal resistance. The type of binder and its quantity in the fabrication of brake pads is of great importance in overcoming fade. The objective of this study is to fabricate phenolic resin brake pad samples reinforced with lignocellulosic banana fiber, which can resist brake fade and have high thermal stability. Four different brake pad samples BP-0, BP-7, BP-14 and BP-21, with different relative amounts of phenolic resin and banana fiber were formulated and tested on a pin on disc tribometer. The friction tests were carried out at a high temperature and high loading. The thermal stability of samples was examined by TGA and DSC techniques. The results show substantial improvement in friction, fade and thermal stability for sample BP-7 comprising of 7% banana fiber and 28% phenolic resin under high temperature and high loading.

Friction and Wear Characteristics of Rubber Resin-Bonded Metallic Brake Pad Materials

This paper aims to present comparative study of friction and wear characteristics of non-asbestos rubber resin bonded metallic based brake pad material. Friction material was compression moulded and machined to a sample size. Their physical and mechanical properties were studied. Experiments were conducted using Pin-on-disc test set-up against EN31 disc. Coefficient of friction and wear was measured for metallic based brake materials at varying conditions of temperature, sliding velocity, pressure and sliding distance. When brake pads are in contact with brake disc, heat is generated hence thermal behaviour of metallic based brake material and its impact on friction and wear were studied. Experiments, based on Taguchi’s analysis technique, using L9 orthogonal array were performed. On the basis of experimental results and S/N ratio analyses, ranking of the parameters have been done. It was found that temperature (95.37 %) and sliding velocity (2.99 %) are most affecting parameters in friction, However temperature (82.96 %) and pressure (6.80) in wear. The elemental composition of metallic based brake material was measured by EDS technique. SEM micrographs of brake pad samples were tested at different magnifications. Further detailed studies are suggested to evaluate wear rate, stopping distance under simulative test conditions alternate to asbestos based brake pad material.

Tribological properties of automotive brake pads containing peanut shell powder

In this study, the effect of peanut shell powder content on the tribological properties of automotive brake pads was investigated experimentally. Brake pads are intended to be resistant to environmental conditions such as abrasion, friction, temperature and humidity. Therefore, brake pads are formed by a combination of materials with many different properties. In this study, four brake pad samples containing different amounts of peanut shell powder were designed and produced. The added peanut shell powder is balanced with the filler in the content and the amount of other components was constant. Samples were produced by conventional dry mixing method. A special design brake tester with a gray cast iron disc was used to determine the wear and friction characteristics of the samples. All tests were performed according to appropriate standards. According to the results obtained, the availability of peanut shell powder in brake pads has been evaluated and categorized according to its characteristics.

Thermo-Mechanical Properties of Motor Vehicle Brake Pad Using Periwinkle Shell and Treated Cow Bone as Filler

Brake pad was produced using periwinkle shell and treated cow borne as base materials, phenolic resin as binder, material, aluminum oxide, copper oxide and zinc oxide as abrasive, and graphite as friction modifier. The particulate size of the filler materials considered was 250µm, Five samples were produced (Samples A, B, C, D and E) witht composition ratios of 60/25, 55/30, 40/35, 45/40 and 40/45 cow bone/periwinkle shell hybrid filler respectively. The produced brake pad samples were evaluated by testing the mechanical, thermal and physical properties. The hardness test showed that as the filler loading increases, there was a steady increase in hardness strength of the material and sample E showed (100.0) most closest hardness value to the required standard (101.0 Shore). The abrasion resistance showed a decrease with increasing filler loading, which could be due to poor interfacial adhesion between binder (PR) and other components due to poor distribution ratio of the filler quantity in the matrix (binder). The impact strength test result revealed that the higher the filler loading, the lower the average impact strength and samples A, B and C met the required standard brake pad impact strength; except for samples D and E, which could be due to the decrease in the quantity of binder (PR). The water absorption test result showed progressive increase in water absorption with increasing filler loading. Samples A and B with water absorption of 5.56% and 6.25% respectively were found to fall wthin the range of the required standard of 4.5%. The coefficient of friction test result showed a steady decrease as the filler loading increased, however, sample E with 0.36µ exhibited a coefficient of friction within the required standard range for automobile vehicles with a coefficient of fiction range of 0.35 – 0.42 µ. The Therrmo Gravimetric Analysis (TGA) test result for sample A was chosen because it proved to give superior performance over others. Sample A showed a percent weight loss as the temperature increased from 299.00°C to 88714°C. Sample A showed thermal stability at 299°C with degradation setting in at 470.07°C and with a percent weight loss of 24.715%.

Advanced Friction–Wear Behavior of Organic Brake Pads Using a Newly Developed System

The objective of this study was to investigate the influence of an advanced performance system on the tribological behavior of brake pad material using a specially designed brake pad tester system following standard SAE J-661. The tribological behavior and friction and wear characteristics of the organic brake pad samples were evaluated. During braking tests, the samples, in contact with a cast iron disk, were studied at different disc speeds, temperatures, and braking cycles under a constant pressure. In order to understand the friction and wear behavior, the unworn surfaces, worn surfaces, and wear debris were characterized by means of scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). Furthermore, the surface characteristics and differences in the wear modes of the brake pad samples were examined. Wear debris was permitted to deform the brake pad surfaces, leading to friction layers and enabling the estimation of the friction behavior of the brake pads. The results showed that the best friction–wear behavior was obtained with lower braking cycles at low speeds and temperature. Thus, the newly developed brake pad tester system proved very effective in evaluating the performance of the brake pad samples.

Evaluation of The Physical Properties of Hazelnut Shell Dust-Added Brake Pad Samples Treated With Cryogenic Process

After understanding that asbestos fibers are harmful to human health; researchers have investigated for alternative and eco-friendly materials. Agricultural products can be an example of these alternative and environmentally friendly materials because they are easily supplied . Thus, in this study, asbestos-free automotive brake pads produced from %7 hazelnut dusts with other seventeen additives. Hazelnut shell is preferred because it is widespread in our country. Cryogenic process applied at -80°C to the brake pads. Before and after cryogenic treatment, the produced brake pads properties such as water absorption, hardness test, porosity and microstructural examinations were investigated. The hardness values of brake pads increases after cryogenic and cyclic-cryogenic process. The highest values obtained for the B-CYC sample.

Organik Katkılı Fren Balatası Numunelerinin Su ve Yağ Emme Özelliklerinin Karakterizasyonu

Organik Katkılı Fren Balatası Numunelerinin Su ve Yağ Emme Özelliklerinin Karakterizasyonu

The Determination of the Effect of Mixture Proportions and Production Parameters on Density and Porosity Features of Miscanthus Reinforced Brake Pads by Taguchi Method

Brake pads are generally consisted of five different component groups. These groups are named as reinforcements, binders, abrasives, lubricants and fillers. Each of these groups has its own function such as to improve friction property, wear resistance, to increase strength, and to reduce porosity and noise. In this study, Miscanthus as reinforcement, cashew as lubricant, alumina as abrasive, calcite as filler, and phenolic resin as binder were used to produce composite ecological brake pad samples. Brake pads are usually developed through trial and error method and therefore, the evaluation process became complicated and time consuming due to the multiplicity of components, randomly selected mixing ratios, results obtained from the experiments, etc. and so Taguchi method is utilized to get rid of these difficulties of trial and error method. This study was made in order to determine the influence level of the brake pad ingredients and some production parameters to the density and porosity features of the brake pad samples. The ecological brake pad samples were manufactured and experiments were conducted to Taguchi Method L32 orthogonal array. According to the ANOVA (Analysis of Variance) tables and other graphical results obtained from Taguchi method, the density feature of brake pad samples are more influenced by the mixture proportion factors and moulding temperature, curing time and curing temperature factors have a minor effect on porosity feature of brake pad samples.

Design, construction and performance of a novel brake pad friction tester

Determination of the tribological behavior of brake pads under real environmental conditions is an important and critical task which can significantly impact the automotive industry. Most studies simulate or measure the variants by indirect methods and accept them as true results. The new computer-controlled, interactive brake pad friction tester presented in this study was developed for this purpose. The major components of the machine, which are operated simultaneously, include: a proportional pressure-controlled hydraulics power pack, a mechanical transmission system with electromagnetic clutch, and a brake and automation control with SCADA computer analysis interface. Compared to other friction testing machines, a very important innovation of the newly developed friction tester allows for the testing of the brake pad samples and measuring of the noise level both to be performed with high precision under real conditions. Moreover, this friction tester is capable of determining the friction coefficients; wear behavior, temperature, and life intervals of brake pad samples. This novel brake pad system is relatively cheaper and measures effective friction coefficients more accurately. The uncertainty in measurements for friction coefficient and wear rate was approximately calculated as ±0.0135 and ±0.170 in all of experiments, respectively. In this study, the machine performance was carried out to evaluate the friction behavior of non-asbestos brake pad samples reinforced with hazelnut shell powder according to the standard brake lining quality control testing procedure (SAE J661).

The effect of the brake pad components to the some physical properties of the ecological brake pad samples

In this study, brake pad components in powder form such as miscanthus, cashew, alumina, phenolic resin and calcite, were used to manufacture ecological brake pads. In the brake pad applications trial and error method is often used to find the optimum proportion providing the best characteristics of the component in composite. The evaluation process became complicated and time consuming due to the number of components used for the manufacture of brake pad, randomly selected mixing ratios, many samples produced with trial and error method and a vast variety of results obtained from the measurements. Taguchi method was utilized in order to determine how the compositions of the brake pad components in the range of 5-20 wt. % had an effect on the properties of the brake pads. As a result of the experiments such as density, hardness, porosity and wear rate, the characteristics of the brake pad samples were more affected by the proportions of Miscanthus and phenolic resin in the mixture.

Influence of magnetic powders on the tribological performance of a novel magnetic brake material

By adding magnetic powders into matrix material, it has been proved to be a creative approach to improve tribological properties of brake materials. In this paper, a novel magnetic brake material with Nd–Fe–B and nano-Fe3O4 was developed, and the influential mechanism of these two magnetic powders and their content on the friction and wear performance was deeply discussed. Firstly, some experiments were carried out to investigate the tribological performance and influential mechanisms of four groups of brake pad samples with different magnetic powders. Furthermore, based on these results, further experiments for investigating the influence that Nd–Fe–B contents have on the tribological properties were conducted. According to the theoretical analysis about experiments, it was concluded that nano-Fe3O4 is beneficial to promote the formation of friction film and has certain lubricant effects. However, Nd–Fe–B has double effects on the formation of friction film. It will have positive effects when its content is less than a certain value. Otherwise, it will destroy the structure of friction film. Conclusively, it is believed that this study will be significantly valuable and meaningful for developing new brake materials and improving safety reliability of mechanical brakes.

Toxicity and mutagenicity of low-metallic automotive brake pad materials

Organic friction materials are standardly used in brakes of small planes, railroad vehicles, trucks and passenger cars. The growing transportation sector requires a better understanding of the negative impact related to the release of potentially hazardous materials into the environment. This includes brakes which can release enormous quantities of wear particulates. This paper addresses in vitro detection of toxic and mutagenic potency of one model and two commercially available low-metallic automotive brake pads used in passenger cars sold in the EU market. The model pad made in the laboratory was also subjected to a standardized brake dynamometer test and the generated non-airborne wear particles were also investigated. Qualitative “organic composition” was determined by GC/MS screening of dichloromethane extracts. Acute toxicity and mutagenicity of four investigated sample types were assessed in vitro by bioluminescence assay using marine bacteria Vibrio fischeri and by two bacterial bioassays i) Ames test on Salmonella typhimurium His− and ii) SOS Chromotest using Escherichia coli PQ37 strain. Screening of organic composition revealed a high variety of organic compounds present in the initial brake pads and also in the generated non-airborne wear debris. Several detected compounds are classified by IARC as possibly carcinogenic to humans, e. g. benzene derivatives. Acute toxicity bioassay revealed a response of bacterial cells after exposure to all samples used. Phenolic resin and wear debris were found to be acutely toxic; however in term of mutagenicity the response was negative. All non-friction exposed brake pad samples (a model pad and two commercial pad samples) were mutagenic with metabolic activation in vitro.

Development and Assessment of Composite Brake Pad Using Pulverized Cocoa Beans Shells Filler

Application of asbestos in friction material after a very long period is now discouraged due to its carcinogenic nature. There is need for alternative (human friendly) friction material. Hence the development of asbestos-free friction material from an agro-waste (cocoa beans shells - CBS) as filler element cum other additives was undertaken using powder metallurgy technique. The particulate size of the filler material considered was 300µm and epoxy resin was used as binder. The produced brake pad samples were analyzed by evaluating their mechanical, physical, and tribological properties. Based on the investigated properties of the developed brake pad, reducing the filler content increased the wear rate, tensile strength, compressive strength, while hardness, density, water absorption, oil absorption and thermal conductivity varied differently. Coefficient of friction increased with increase in the filler wt%. The results showed that CBS particles could be effectively used as replacement for asbestos in automotive brake pad manufacture.

The PM10 fraction of road dust in the UK and India: Characterization, source profiles and oxidative potential

Most studies of road dust composition have sampled a very wide range of particle sizes, but from the perspective of respiratory exposure to resuspended dusts, it is the PM10 fraction which is of most importance. The PM10 fraction of road dust samples was collected at two sites in Birmingham, UK (major highway and road tunnel) and one site in New Delhi, India. Dust loadings were found to be much higher for New Delhi compared to Birmingham, while concentrations of several species were much higher in the case of Birmingham. Detailed chemical source profiles were prepared for both cities and previously generated empirical factors for source attribution to brake wear, tyre wear, and crustal dust were successfully applied to the UK sites. However, 100% of the mass for the Indian site could not be accounted for using these factors. This study highlights the need for generation of local empirical estimation factors for non-exhaust vehicle emissions. A limited number of bulk road dust and brake pad samples were also characterized. Oxidative potential (OP) was also determined for a limited number of PM10 and bulk road dust samples, and Cu was found to be a factor significantly associated with OP in PM10 and bulk road dust.

The Study of Disc Brake Noise on Three Different Types of Friction Materials

This work investigates the effect of road grit particles and material compositions on disc brake squeal noise. Three different Non Asbestos Organic (NAO) brake pad samples and road particles with a size range between 400 μm to 500 μm are used in the squeal experiment. The relationship between the existence of road particle with the noise occurrence were studied through the change in pressure level, friction coefficient (CoF), sound pressure level (SPL) and material composition. The material compositions were analyzed before and after squealing condition using energy dispersive X-ray analysis (EDX). Result has shown the road particles contribute to the emission of squeal noise and the increasing of some material composition of brake friction material components.

Effect of Pressing Pressure on Density and Hardness of Powder Miscanthus Reinforced Brake Pads

The aim of this paper is to develop new natural fibre reinforced for automotive brake pad application. For this purpose, new brake pad sampleswere produced using Miscanthus as reinforcement ingredient. The other ingredients are Cashew, Alumina, Phenolic Resin, and Calcite. Three different laboratory formulations were prepared with varying Miscanthus fibre contents from 10, 25, and 40 (wt) and these formulations were moulded four different moulding pressure values such as 50, 100, 200, and 300 MPa. Sieve analysis, density, apparent density, and hardness properties of brake pad samples produced are examined.

The effect of boron on the performance of automotive brake

Friction material in an automotive brake system plays an important role for effective and safe brake performance. A single material has never been sufficient to solve performance related issues. Current research aimed to examine properties of Boron mixed brake pads by comparing them with the commercial brake pads. Friction coefficient of Boron mixed brake pads and commercial brake pads were significantly different and increased with the increase in surface roughness. The abrupt reduction of friction coefficient is more significant in commercial brake pad samples than in Boron mixed brake pad formulations. Fade occurred in commercial brake pad sample at lower temperatures. Boron formulations are more stable than their commercial counterparts.

Morphology and properties of periwinkle shell asbestos-free brake pad

The development of asbestos-free automotive brake pad using periwinkle shell particles as frictional filler material is presented. This was with a view to exploiting the characteristics of the periwinkle shell, which is largely deposited as a waste, in replacing asbestos which has been found to be carcinogenic. Five sets of brake pads with different sieve size (710–125μm) of periwinkle shell particles with 35% resin were produced using compressive moulding. The physical, mechanical and tribological properties of the periwinkle shell particle-based brake pads were evaluated and compared with the values for the asbestos-based brake pads. The results obtained showed that compressive strength, hardness and density of the developed brake pad samples increased with decreasing the particle size of periwinkle shell from 710 to 125μm, while the oil soak, water soak and wear rate decreased with decreasing the particle size of periwinkle shell. The results obtained at 125μm of periwinkle shell particles compared favourably with that of commercial brake pad. The results of this research indicate that periwinkle shell particles can be effectively used as a replacement for asbestos in brake pad manufacture.

Mechanical Properties and Wear Behavior of Brake Pads Produced from Palm Slag

Brake pads are important safety devices in vehicles. An effort to avoid the use of asbestos in brake pads has led to the development of asbestos-free brake pads that incorporate various organic and inorganic fillers. Palm slag as a filler in brake pads was investigated in this paper. Different processing pressures were employed during production of samples through compression molding. The properties examined included hardness, compressive strength, and wear behavior. The results showed that brake pad samples prepared with 60 tons of compression pressure resulted in the most desirable properties. Hence, palm slag has its own potential for use as a filler in asbestos-free brake pads.