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Article
Publication date: 27 July 2022

Saikrishnan G., Jayakumari L.S. and Vijay R.

The purpose of this paper is to deal with the tribological study on the brake pads developed using various purity-based graphitized graphite.

Abstract

Purpose

The purpose of this paper is to deal with the tribological study on the brake pads developed using various purity-based graphitized graphite.

Design/methodology/approach

This paper deals with developing copper-free brake pads by using graphite as a key lubricant produced using a graphitization process with purity percentages (85, 90 and 95%). The brake pads were developed using traditional manufacturing processes and evaluated for their physical, chemical, thermal and mechanical properties as per industrial standards. Fade and recovery characteristics were analyzed using a full-scale inertia brake dynamometer as per JASO-C-406. The scanning electron microscope was used to analyze the worn surfaces of the brake pads.

Findings

The testing findings reveal that the brake pads with 95% graphitized graphite showed better shear strength with good adhesion levels and lesser density, hardness, acetone extract value, loss on ignition and higher porosity. Effectiveness studies of brake pads with graphite (95% graphitized) showed better results at higher pressure speed conditions than others because of better plateau formation and adequate lubrication.

Originality/value

This paper discusses graphitized graphite of different purity influences brake pad's tribological performance by modifying tribo-films and reducing friction undulations.

Details

Industrial Lubrication and Tribology, vol. 74 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 30 December 2019

Vijay R., Manoharan S. and Lenin Singaravelu D.

This paper aims to deal with the effect of natural barytes purity levels on the tribological performance of brake pads.

Abstract

Purpose

This paper aims to deal with the effect of natural barytes purity levels on the tribological performance of brake pads.

Design/methodology/approach

In this study, brake pads were developed by varying three different natural barytes without varying other ingredients. The brake pads were developed as per the standard 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 a full-scale inertia brake dynamometer. Worn surface analysis was done using scanning electron microscope coupled with elemental mapping.

Findings

The experimental results indicate that the brake pads filled with natural barytes 95% purity had good physical, chemical and mechanical properties with stable friction and less wear rate due to reduced impurity level preventing frictional undulations.

Originality/value

This paper explains the effect of the purity level of natural barytes in brake pads formulation to enhance the tribological performance by altering tribofilms and preventing friction undulations.

Details

Industrial Lubrication and Tribology, vol. 72 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 22 September 2022

Justin Antonyraj I., Vijay R., Sathyamoorthy G. and Lenin Singaravelu D.

This paper aims to discuss the influence of graphite with varying purity on the tribological performance of brake pads.

Abstract

Purpose

This paper aims to discuss the influence of graphite with varying purity on the tribological performance of brake pads.

Design/methodology/approach

Three distinct brake pads were created within the scope of this experiment by varying the graphite purity without affecting the other components. The brake pads were made using a traditional manufacturing procedure, and industry standards were used to test the chemical, physical and mechanical properties of the newly produced brake pad. A full-scale inertia brake dynamometer was used to determine the material’s tribological characteristics. The worn surfaces of the brake pads were examined using a scanning electron microscope.

Findings

The test results indicate that brake pads containing 99% pure graphite (artificial grade) displayed good physical, chemical and mechanical features, such as consistent friction and a reduced rate of wear because of the lower impurity level, which eliminates frictional undulations.

Originality/value

This paper discusses the influence of graphite purity on the tribological performance of brake pads by modifying tribofilms and reducing friction undulations.

Details

Industrial Lubrication and Tribology, vol. 75 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 May 2017

Talib Ria Jaafar, Noor Iswadi Ismail, Mohd Fauzi Ismail and Eliasidi Abu Othman

This study aims to investigate the effect of different volume percentage (Vol.%) of steel fibre on the pressure, surface temperature and speed sensitivity behaviour during braking

Abstract

Purpose

This study aims to investigate the effect of different volume percentage (Vol.%) of steel fibre on the pressure, surface temperature and speed sensitivity behaviour during braking process as known brake effectiveness and to propose the best steel fibre Vol.% in the formulation.

Design/methodology/approach

Three brake pads composed of three different steel fibre volume percentages were fabricated through powder metallurgy route. Selecting one sample as based formulations, steel fibre (Vol.%) was decreased and increased by 50 per cent in the other two samples, respectively. The other ingredients are proportionally increased and decreased accordingly to the base formulation. The samples were tested for determining their hardness, porosity and coefficient of friction (COF) using Rockwell hardness tester, hot bath and brake inertia dynamometer, respectively.

Findings

Test results indicated that Sample T1 which composed of 9 Vol.% of steel fibre had the lowest COF and was sensitive to applied pressure, surface temperature and speed. The samples which composed of 18 and 27 Vol.% of steel fibre were having the same trend of COF and were sensitive to surface temperature and speed. Sample T which composed of 18 Vol.% of steel fibre had lower brake pad and disc lost as compared to Sample T2 which composed of 27 Vol.%. Mechanical properties did not show any significant correlation with COF sensitivity with temperature, speed and pressure.

Originality/value

The sample with 18 Vol.% of steel fibre was found to be the best formulation which produced acceptable COF; less sensitive to temperature, pressure and speed during braking process; and better wear resistance of brake pad as well as the rotor.

Details

Industrial Lubrication and Tribology, vol. 69 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 28 August 2019

Saikrishnan G., Jayakumari L.S., Vijay R. and Lenin Singaravelu D.

The purpose of this study is to investigate the influence of commercially available iron–aluminum alloy compared to copper, iron and aluminum powders on the tribological…

Abstract

Purpose

The purpose of this study is to investigate the influence of commercially available iron–aluminum alloy compared to copper, iron and aluminum powders on the tribological performances of friction composites. The main objective is to replace copper from the friction composite formulations.

Design/methodology/approach

In this study, friction composites were fabricated as of standard brake pads using commercially available iron–aluminum alloy and compared to copper powder, iron powder and aluminum powder-based without varying the other ingredients. The brake pads were developed as per the industrial procedure. The physical, mechanical and thermal properties of the developed brake pads were analyzed as per industrial standards. Tribological properties were analyzed using the chase test. Initial speed and deceleration tests in a real-time braking scenario were performed using a full-scale inertia brake dynamometer. Worn surface analysis was done using a scanning electron microscope.

Findings

The results indicate that iron–aluminum alloy (mechanomade)-based friction composites possess good physical, chemical, thermal and mechanical properties with stable fade and recovery characteristics due to its composition and flake morphology. During initial speed and deceleration braking conditions, iron–aluminum alloy also showed good tribological behavior.

Originality/value

This paper explains the influence of commercially available iron–aluminum alloy in friction composites in enhancing tribological performance by its composition and flake morphology, which could potentially replace copper in friction composites by solving subsequent problems.

Details

Industrial Lubrication and Tribology, vol. 72 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 13 April 2022

Sathyamoorthy G., Vijay R. and Lenin Singaravelu D.

This study aims to discuss the impact of using bio-polymer (kraft lignin) in the formulation of passenger vehicle disc brake pads (as a substitute for cashew nutshell liquid…

Abstract

Purpose

This study aims to discuss the impact of using bio-polymer (kraft lignin) in the formulation of passenger vehicle disc brake pads (as a substitute for cashew nutshell liquid [CNSL]-based friction dust) and investigate the characteristics of the pads.

Design/methodology/approach

Within the scope of this investigation, three different brake pads were generated by altering the biopolymer-lignin content in conjunction with the friction dust from CNSL without modifying the other components. The brake pads were created in accordance with industry-standard practices. Industrial standards were used to evaluate the newly created brake pad’s thermal, physical and mechanical qualities. The tribological properties of the materials were determined using a full-scale inertia brake dynamometer. The scanning electron microscope examined the worn surfaces in conjunction with elemental mapping.

Findings

The test findings suggest that the brake pads filled with biopolymer-lignin and CNSL-based friction dust (as a partial replacement 50%) exhibited excellent thermal, physical, mechanical characteristics, as well as steady friction and low wear rate.

Originality/value

A bio-polymer (kraft lignin) in friction composites has the potential to produce eco-friendly brake pads and improve the tribological performance of its copper free-composition, which might be used to replace CNSL-based friction dust in friction composites by addressing the issues raised in this work.

Details

Industrial Lubrication and Tribology, vol. 74 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 November 1956

This American designed, British built Dunlop dynamometer is able to test tyre, wheel and brake under closely simulated conditions.

Abstract

This American designed, British built Dunlop dynamometer is able to test tyre, wheel and brake under closely simulated conditions.

Details

Aircraft Engineering and Aerospace Technology, vol. 28 no. 11
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 6 October 2023

Youjie Chen, Rong Fu, Junying Yang, En Zhang, Linlin Su and Fei Gao

This study aims to clarify the relationship between the coefficient of friction (COF) and temperature of aluminum-based brake discs.

Abstract

Purpose

This study aims to clarify the relationship between the coefficient of friction (COF) and temperature of aluminum-based brake discs.

Design/methodology/approach

Three friction blocks with different COFs are examined by a TM-I-type reduced-scale inertial braking dynamometer. On this basis, the thermo-mechanically coupled model of friction pairs is established to study the evolution of brake disc temperature under different COFs using ADINA software.

Findings

Results indicate that the calculated disc temperature field matches the experimental well. The effect of COF on the peak temperature is magnified by the braking speed. With the COF increasing, the rise rate of instantaneous peak temperature is accelerated, and the dynamic equilibrium period and cooling-down period are observed in advance. The increase in COF promotes the area ratio of the high-temperature zone and the maximum radial temperature difference. When the COF is increased from 0.245 to 0.359 and 0.434 at 140 km/h, the area ratio of high-temperature zone increases from 12% to 44% and 49% and the maximum radial temperature difference increases from 56°C to 75°C and 83°C. The sensitiveness of the axial temperature difference to the COF is related to the braking time. The maximum axial temperature difference increases with COF in the early stages of braking, while it is hardly sensitive to the COF in the later stages of braking.

Originality/value

The effect of COF on the aluminum-based brake disc temperature is revealed, providing a theoretical reference for the popularization of aluminum-based brake discs and the selection of matching brake pads.

Details

Industrial Lubrication and Tribology, vol. 75 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 June 1963

WITH the advent of supersonic flight the effects of kinetic heating have made themselves felt throughout the design of the aircraft and its associated systems and equipment…

Abstract

WITH the advent of supersonic flight the effects of kinetic heating have made themselves felt throughout the design of the aircraft and its associated systems and equipment. Aircraft tyres (forming part of the retracted undercarriage) normally rest close to the skin of an aircraft which is subjected to an increase in temperature at supersonic speeds. In order to be able to test satisfactorily tyres for supersonic aircraft, the Aviation Division of The Dunlop Rubber Company has installed test equipment which simulates the various heating conditions likely to be encountered, and these facilities are described in the following article.

Details

Aircraft Engineering and Aerospace Technology, vol. 35 no. 6
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 September 1943

ATTENTION has of recent months been focused upon the fact that large numbers of aero‐engines in this country are tested by means of plant which does not recover the engine power…

Abstract

ATTENTION has of recent months been focused upon the fact that large numbers of aero‐engines in this country are tested by means of plant which does not recover the engine power, or put it to useful work.

Details

Aircraft Engineering and Aerospace Technology, vol. 15 no. 9
Type: Research Article
ISSN: 0002-2667

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