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The aim of the research is to investigate the ceramic brake lining on the brake performance.Design/methodology/approach – The brake lining which has new formulation has been produced by using various additive materials. Various techniques have been used in the production of brake lining. These ceramic linings were subjected to friction and wear tests under different loads, and changes in the hardness and microstructures were examined.Findings – As a result of this study, the following findings are reported. A direct proportional was not found between hardness and wear resistance due to the complexity of composite structure. Kevlar fibers were homogeneously distributed in the matrix and therefore, very few microvoids were observed in the structure. Similarly, stone wool was well spread out the braking pad and hence decreased the microvoids' occurrence. Heat treatment supplied more homogeneous structure and hence, microstructural variations were minimised during the brake action. On the other hand, heat treatment decreased the hardness of glass fiber reinforced specimens and increased the density. Each specimen was affected from the environmental conditions. However, water affected all specimens more than the other environmental conditions, such as salty water, oil and braking liquid. With the increasing of temperature, the ingredients in the braking pad were affected other due to better diffusion. On the other hand, hardness of specimens increases and density decreases due to heat treatment and also specific wear ratio changes.Research limitations/implications – Limitations in the present research are as follows: two different pressures and eight different temperatures were used and brake linings were subjected to wear test, hardness tests, microstructures were examined.Practical implications – For future work, instead of buying expensive brake lining, new and cheaper ceramic linings are produced. By this process, economic benefit can be gained and also environmental protection can be succeeded in producing such asbestos free brake linings.Originality/value – This paper fulfills 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.

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 aim of the research is to investigate wear performance of some phenolic composites with boric acid.

The brake lining which has new formulation has been produced by using various additive materials. Various techniques have been used in the production of brake lining. These phenolic composites were subjected to friction and wear tests under different loads, and changes in the hardness and microstructures were examined.

As a result of this study, the following findings are reported. It was not found a direct proportionality between hardness and wear resistance due to the complexity of composite structure. Heat treatment application changed the microstructure of the brake lining, and increased the hardness and also decreased the density. With the increasing of temperature, the ingredients in the braking pad were affected other due to faster diffusion. On the other hand, hardness of specimen increases due to heat treatment and also specific wear ratio changes. As a filling material, barite was used due to better performance in the environmental conditions. More wear was observed in the bigger powder particles comparing to the smaller ones due to more structural loss. Squealing was heard in fiber un‐reinforced brake lining due to more barite content. In the present samples, boric acid deports the water and establishing the structural equilibrium. Therefore, these samples supplied higher and stable friction of coefficient. Also, heat treatment supplied a stable friction coefficient. With the increasing of copper powder into specimens, friction coefficient also increased. Heat treatment made the increment of hardness of specimens and also it made effect on the hardness with strengthening bonds of interparticles.

Limitations in the present research are as follows: two different pressures and eight different temperatures were used and brake linings were subjected to wear test, hardness tests, microstructures were examined.

For future work, instead of buying expensive brake lining, new and cheaper phenolic linings are produced. By this process, economic benefit can be gained and also environmental protection can be succeeded in producing such asbestos free brake linings.

This paper fulfills 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.

The purpose of this paper is to evaluate experimentally the influence of different surface roughness of the contacting disc on tribological performance of the non-asbestos brake friction material (BFM).

Taguchi method was applied to design an experiment using three different discs of gray cast iron with different surface roughness, which is measured using optical profilometer. These discs were subjected to sliding against pins prepared with the developed non-asbestos BFM, using pin on disc friction and wear monitor.

The experimental results shows that the disc 2 (Ra = 3.77 µm) gives wear of 22.78 µm and coefficient of friction of 0.462, which is recommended for extreme brake performance. Analysis of Taguchi design revealed that the disc surface was most significant parameter among the parameters under study.

During braking, continuous sliding between the BFM and brake disc or drum not only results into wear of BFM but also changes the surface finish of the brake drum or disc. This leads to variation in surface topography of the drum or disc surface with application of brakes, which further affects the characteristics of the BFM.

The tribological performance of BFM depends upon the topography of the surface on which it was sliding. To get best performance of the non-asbestos friction materials, disc having moderate surface finish is recommended. Scanning electron microscope micrographs had shown the different plateaus formed and energy-dispersive X-ray spectroscopy spectra identified presence of different chemical elements prior to sliding of the pins surface over different discs surface topography.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0120/

In order to improving the braking reliability and assuring the driving safety of automobiles, this paper aims at the wear performance and its online monitoring of its brake lining.

The wear performance of the semimetal brake lining for automobiles was investigated on a self-made braking tester for disc brakes. Based on the experimental data, an intelligent forecasting model for the wear rate was established by the artificial neural network (ANN) technology. And by taking it as a core, an online braking wear monitoring system for automobiles was designed.

It is shown that the wear rate rises obviously with the increasing of both initial braking velocity and braking pressure. By the contrast, the initial braking velocity affects the wear rate more seriously. The ANN model trained by the experimental data shows favorable capability for predicting of the wear rate. The big forecasting errors at high velocity and heavy load should be attributed to the jumping of the wear rate at this period. Based on the existed sensors and electronic control unit system of automobiles, the online braking wear monitoring system can be established easily by the ANN technology.

A self-made braking tester for disc brakes was used to test the wear performance, which can simulate better the actual disc braking conditions than the standard pin-on-disc friction tester. An online braking wear monitoring system was designed to help improving the braking reliability and safety of automobiles.

The purpose of this paper is to find the variations of brake lining's frictional performance with braking conditions, and their influence on the braking safety and reliability of automobiles.

As the semimetal brake lining is widely used currently in automobiles, it was selected as the experimental material. By simulating the braking conditions and environment of automobiles, some tribological experiments of the brake lining were investigated on the X‐DM friction tester, when it is paired with the friction disc made of gray cast iron. The influence of braking pressure, sliding velocity and surface temperature on the friction coefficient and its stability coefficient were studied in depth through experiments.

The friction coefficient decreases gradually with the increasing of braking pressure and sliding velocity when the surface temperature is naturally rising. It rises first then falls with the surface temperature rising and the maximal value appears at nearly 200°C. The stability of friction coefficient decreases obviously when the sliding velocity exceeds 30 m/s, the braking pressure exceeds 1.8 MPa and the surface temperature is over 200°C. Based on the experimental results, the authors consider that it is not reliable to execute an emergency braking only by rising the braking pressure when the automobile is driving with a high velocity. In order to reduce the bad influence of high temperature on frictional performance, some effective actions should be taken for cooling the friction disc. What is more, special attention should be paid to the decreasing of frictional stability during the braking with high velocity, pressure and temperature.

This paper studies the influence of braking conditions on friction coefficient and its stability of the semimetal brake lining for automobiles. It is believed that this research may have some actual guidance for enhancing the braking safety and reliability of automobiles.

The purpose of this paper is to provide some useful information on the tribological performance of thermoplastic polyimide (TPI) reinforced with rigid glass fillers of different shapes and sizes under dry, water, and oil lubrication conditions.

Rigid glass fillers of different shapes and sizes are chosen to modify TPI and its mechanical properties are measured. The stress‐strain behaviors of the composites are simulated by the finite element method and the effect of filler morphology is also considered. Furthermore, the tribological performance of the composites is investigated in different environmental media, including air, water, and oil.

It is demonstrated that the toughness of the materials decreases on filling them with rigid glass, and that stress concentration causes cracks around the spherical glass beads, which reduces the material impact strength. Owing to heat moulding technology, glass fiber has certain orientation and absorbs the impact energy effectively. A better wear‐resistant material is obtained by choosing a bigger filler due to its higher bond strength with the matrix. Under water and oil lubrication, the fatigue failure is the main reason for material wear, and fiber‐reinforced TPI has favorable wear‐resistance due to its shape. Meanwhile, glass beads could roll on the contact surface, which polishes the surface and reduces the friction coefficient, and its effect is reduced on oil lubrication for its high viscosity.

This paper analyzes the effect of rigid glass fillers of different shapes and sizes on the mechanical properties and tribological performance of polyimide composites.

This paper aims to deal with the synergistic effect of steel slag-molybdenum disulfide particles on fade-recovery performances of non-asbestos organic friction material.

The brake friction materials were developed by using steel slag and molybdenum disulfide particles as individual and combination in the formulation. The brake friction materials were developed in the form of standard brake pads as per the industrial practice. 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 IS2742-Part-4. Worn surface analysis was done using a scanning electron microscope.

The experimental results indicate that the brake pads filled with a combination of steel slag and molybdenum disulfide showed stable friction and less wear rate due to the synergetic nature of abrasive and lubricant.

This paper explains the influence of steel slag and molybdenum disulfide particles as individual and combined in brake pads formulation to enhance the tribological performance by producing stabilized friction with undulations.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2020-0216/

The purpose of this study was to investigate the use of boric acid as a friction modifier material in brake friction composites and to determine the effect of heat treatment applied during production on braking performance.

The addition of five different amounts of boric acid was balanced with cashew, which is in the friction modifier material group. The samples were produced in the following order: dry mixing, preforming and hot-pressing. The effect of the heat treatment that can be applied after the hot-pressing process on the braking performance was investigated. The tribological and physical properties of the samples were determined using tests performed according to appropriate standards. The microstructures of the friction surfaces were investigated using scanning electron microscopy.

It was observed that the tribological properties of brake friction composites containing 20% by weight of boric acid were improved. It has also been observed that the heat treatment applied after hot pressing increased the friction coefficient of the samples by 7% on average and decreased the specific wear ratio of the samples. When the surface morphologies of the samples are examined, it is seen that the friction layers of the heat-treated samples are wider, and the microvoids and cracks are reduced.

This study showed that boric acid can be used as a friction modifier in brake friction composites. It also revealed the tribological and physical contribution of the applied heat treatment to the composite. Thus, it guides brake friction composite manufacturers in the industry and researchers working in this field.