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The purpose of this paper is to investigate the role of solid lubricants (graphite, coke, ZnS) on brake performance.

In this study, the tribological and surface characteristic of non‐asbestos organic type brake friction materials containing three different solid lubricants (graphite, coke, and ZnS) in different proportions were examined and evaluated experimentally. The coefficient of friction (COF) and wear behavior of the samples were tested on a chase‐type friction tester, and particular emphases were given to the effect of temperature and number of braking cycles on the COF. Each of the lubricants was added to the mixtures in different amounts and seven different brake linings were manufactured, provided that the total amount of solid lubricants and other ingredients were not changed. The worn surfaces of the specimens were analyzed using a scanning electron microscope with energy‐dispersive X‐ray microanalysis.

The experimental results indicate that graphite has a positive effect on the tribological properties of brake linings. However, brake linings containing higher concentrations of ZnS and coke showed an unstable friction coefficient relationship with the temperature and number of braking cycles. The formation of friction layers was detected on the friction surface of these samples, which indicates that an increase in coke and ZnS content increases the discontinuous and unstable friction film areas.

This paper fulfils the effects of solid lubricants (graphite, coke, ZnS) in brake friction materials with detailed tests and analysis.

The purpose of this paper is to study the influence of braking speed at –20 °C on the wear property of high-speed railway braking materials and the temperature also stress analyses of brake disc friction surface.

Friction brake tester was used to simulate the wear test of high-speed railway braking materials at diverse braking speeds (2,100, 2,400, 2,700 and 3,000 rad/min) at –20 °C and the stress and temperature analyses of brake disc friction surface were carried out by COMSOL.

Compared with 20°C, there is initial stress of brake disc friction surface before brake starting; also, the maximum wear depth is larger at –20°C. Besides, at –20 °C, with the rising of braking speed, the graphite particles on the friction surface of brake pad significantly reduce. And scratches and cracks are formed on brake pad friction surface. Besides, the abrasive wear, adhesive wear and thermal cracks of brake disc friction surface are aggravated. Moreover, the maximal worn depth also increase. Meanwhile, the highest temperature and the maximum thermal stress of brake disc friction surface both raise. Furthermore, the temperature and thermal stress gradients at radial direction of brake disc friction surface aggrandize, which makes the thermal cracks on brake disc friction surface further exacerbated.

In this paper, the wear property of the high-speed railway braking materials is studied by combining experiment and simulation. However, due to the low-speed traveling of high-speed railway was mainly studied in this paper, there may be no comprehensive simulation of the real running condition of high-speed railway. At the same time, the working condition of low-temperature environment cannot be completely simulated and controlled.

The research results of this paper provide a basic instruction for other researchers and also provide an important reference for relevant personnel to choose the braking speed of high-speed railway at –20 °C.

The research of this paper provides a brick for the study of high-speed railway braking materials and also provides some references for the safe service of trains in low-temperature environment.

This paper studied the wear property and carried out the simulation analysis of braking materials at –20 °C at diverse braking speed. The research findings provide an important reference for the selection of braking speed of high-speed railway at –20 °C.

This study aims to determine the braking performance of limestone as a filler in brake friction materials.

Samples containing limestone material (30-35-40%), which can be an alternative to brake friction material filler, were produced. The samples were weighed on precision scales, mixed homogeneously and produced using the hot molding method. The physical and tribological properties of the produced samples were determined, and their microscopic analyzes were made with scanning electron microscopy.

As the amount of limestone increased, the density of the samples decreased. The friction coefficient and wear rates were close to each other and within the optimum limits for all samples. Limestone materials can be used instead of barite materials studied in the literature on brake linings. Microcracks were observed only in samples containing 30% and 35% limestone in microscopic images.

In this study, the wear rate, coefficient of friction and microstructures on the friction surfaces of brake friction materials containing limestone were investigated. The usability of limestone as a filler in brake friction materials provides valuable information to researchers and industrial organizations in the brake friction material field.

The purpose of this paper is to investigate the effect of fly ash content on the friction–wear performance of bronze-based brake lining material.

In this study, bronze-based brake linings containing 0-12 weight per cent fly ash were produced by the hot-pressing process. The friction-wear properties of the unreinforced bronze matrix brake lining material and fly ash reinforced samples were investigated using a Chase-type friction tester. The hardness and density of the samples were also determined. The microstructures and friction surfaces of the samples were examined using scanning electron microscopy.

The experimental results showed that the fly ash content significantly affects the friction-wear properties of the brake lining material. It was found that the friction coefficient increases with the increase in the fly ash content for the brake lining materials studied. Moreover, the mass losses in the wear test were lower for the brake linings containing over 4 weight per cent fly ash than unreinforced bronze-based lining material.

This study has proven to be useful in exploring fly ash particles as low cost reinforcing materials in improving the friction–wear performance of bronze-based brake lining material. In addition, the use of fly ash particles in the manufacture of brake lining materials contributes to reducing the production cost of brake linings and to a sustainable environment.

The purpose of this paper, brake friction material samples with six different contents were produced using three different fiber types consisting of variable proportions of huntite mineral and basalt, glass and steel fibers. The friction properties and formation of the transfer film in these friction materials were investigated.

Friction materials were produced using a hot molding method from materials containing 10%–15% huntite in varying proportions, consisting of basalt, glass and steel fibers. The densities and hardness values of the samples were measured. Friction tests were performed using a brake pad friction material tester to determine tribological properties. After the friction tests, microscopic examination of the sample surfaces was performed using scanning electron microscope (SEM) and three-dimensional (3D) surface profilometer devices.

Huntite mineral content and fiber type affected the friction coefficient. With an increase in the amount of huntite, the friction coefficient increased in the friction material samples formed with glass and steel fibers. The fiber type and amount of huntite also affected the transfer film formation. The surface roughness values of all the friction materials decreased with an increase in the amount of huntite. The surface roughness values of the samples with glass fibers were higher than those of other samples.

The importance of using huntite minerals and different fiber types in automotive brake friction materials is emphasized. This will help industrial companies and academics study the tribological properties of friction materials.

The purpose of this study is to deals with the effect of premixed dual metal sulfides (tin disulfide + iron disulfide) as a replacement for antimony trisulfide on the tribological performance of brake friction materials.

In this study, brake friction materials were developed by using premixed dual metal sulfides as a replacement for antimony trisulfide in the formulation. The brake friction materials were developed in the form of standard brake pads as per the industrial practice. Thermal stability was measured for varying ingredients and developed brake pads using thermogravimetric analysis. The physical, mechanical and thermal properties of the developed brake pads were tested as per the industrial standards. The tribological properties were analyzed using the Chase test as per SAE J661. Worn surface analysis was done using a scanning electron microscope.

The experimental results indicate that the brake pads filled with premixed dual metal sulfides had good thermal stability, physical, chemical and mechanical properties with stable friction and less wear rate due to better lubrication preventing friction undulations.

This paper explains the influence of premixed dual metal sulfides as a replacement for antimony trisulfide in brake pads formulation to enhance the tribological performance by preventing friction undulations.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0144/

The purpose of this paper is to investigate use of colemanite (C) upon friction and wear performance of automotive brake lining. Brake lining production with the boron product colemanite addition and braking characterization investigated for development of non-asbestos organic (NAO) brake lining because of negative effects on human health and environmental hazard of asbestos containing linings. During the braking, brake lining is warmed up extremely due to friction, and the high temperature causes to decreasing of breaking performance. Colemanite has high melting temperature, and this makes this material valuable for brake lining.

This study investigated the effect of colemanite (C) upon friction and wear performance of automotive brake lining. Based on a simple experimental formulation, different amounts of boron product colemanite were used and then evaluated using a friction assessment and screening test. In these specimens, half of the samples (shown with H indices) were heat treated in 4 h at 180°C temperature. Friction coefficient, wear rate and scanning electron microscope for friction surfaces were used to assess the performance of these samples.

The results of test showed that colemanite can substantially improve properties of friction materials. The friction coefficient of friction materials modified with colemanite varies steadily with the change of temperature, and the wearing rate of friction materials is relatively low by using colemanite. Heat treatment-applied samples (CH) have provided a higher and stable friction coefficient. These results indicate that colemanite has ideal application effect in various friction materials.

This paper fulfils an identified information and offers practical help to the industrial firms working with brake lining and also to the academicians working on wear of materials. Parallel results have been presented between previously reported and present study, in view of brake characteristics and wear resistance. Use of the lower cost and productive organic sources of material are the main improvement of the present study.

In order to improve the braking safety of mine hoisters, this paper aims to focus on the continuous repetitious emergency braking conditions to investigate an abnormal frictional phenomena called “Frictional catastrophe (FC)” and its mechanisms.

The non‐asbestos brake shoe of a mine hoister was selected as frictional material and its paring material is 16Mn steel. The tribological properties of the brake shoe were tested on the pad‐on‐disc friction tester by the simulation of continuous emergency braking conditions. The thermal analysis experiments, the temperature field simulations and the SEM analysis of the brake shoe were accomplished to reveal the mechanisms of the FC.

It was found that the friction coefficient of the brake shoe sometimes falls suddenly during braking. This abnormal frictional phenomena is called “Frictional catastrophe (FC)”. It is considered that the friction heat, which is accumulated rapidly by the braking on the surface of the brake shoe, makes the surface layer material qualitatively change from the solid state to a mixed state composed of gases, liquids and solid. The frictional modality of the braking changes accordingly from dry friction to lubrication with gases and liquids. The sudden lubrication makes the friction coefficient fall suddenly and induces the FC phenomena.

An abnormal tribological phenomena called “Frictional catastrophe (FC)” was found in this paper. The investigations about the behaviors and mechanisms of the FC are considered helpful for improving the braking safety of mine hoisters and other machines.

This study aims to clarify the relationship of friction material type and brake disc temperature through braking experiment.

The braking performances of resin materials (RM), semimetallic materials (SM) and copper-based powder metallurgy materials (PM) friction blocks mating with forged steel brake disc were examined based on TM-I-type reduced-scale inertial braking dynamometer. The brake disc surface temperature was recorded by infrared thermal camera during braking.

Experimental results indicate that the thermal wear resistance of three friction materials differs with mental content, resulting in the deviation of pad-disc system contact state during braking, thus forming different temperature distribution on the brake disc surface. The peak temperature on the disc face of RM (190°C) is 36.6% and 45.4% lower than that of PM (300°C) and SM (348°C) at 160 km/h. The maximum radial temperature deviation of PM (35°C) is approximately three times than that of RM (12°C) and 40% higher than that of SM (25°C) at 50 km/h, whereas the maximum temperature deviation of SM (97°C) is six times than that of RM (16°C) and 31% higher than that of PM (74°C) at 160 km/h.

The effect of friction material type on the disc surface temperature distribution is revealed, which provides a meaningful reference for the design of brake friction pairs and choice of brake pad materials.

This paper aims to thrash out friction and wear properties of automobile brake lining reinforced by lignin fiber and glass fiber in braking process.

ABAQUS finite element software was used to analyze thermo-mechanical coupled field of friction materials. XD-MSM constant speed friction testing machine was used to test friction and wear properties of friction material. Worn surface morphology and mechanism of friction materials were observed by using scanning electron microscope.

The results show that when the temperature was below 350°C, worn mechanism of MFBL was mainly fatigue wear and abrasive wear, and worn mechanism of GFBL was mainly fatigue wear because MFBL contained lignin fiber. Therefore, it exhibits better mechanical properties and friction and wear properties than those of GFBL.

Lignin fiber can improve mechanical properties and friction and wear properties of the automobile brake lining.