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

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.

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

Materials ◽

10.3390/ma14040884 ◽

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.

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Deposition and Tribological Properties of CVD Diamond/Diamond-Like Carbon Composite Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.565.615 ◽

2012 ◽

Vol 565 ◽

pp. 615-620

Author(s):

Bin Shen ◽

Liang Wang ◽

Su Lin Chen ◽

Fang Hong Sun

Keyword(s):

Surface Morphology ◽

Composite Film ◽

Tribological Properties ◽

Composite Films ◽

Cvd Diamond ◽

Carbon Composite ◽

Dry Sliding ◽

Diamond Like Carbon ◽

Dlc Film ◽

Bonding State

The CVD diamond/diamond-like carbon composite film is fabricated on the WC-Co substrate by depositing a layer of Diamond-like Carbon film on the surface of conventional Micro- or Nano-crystalline diamond film. The hot filament chemical vapor deposition (HFCVD) method and vacuum arc discharge with a graphite cathode are adopted respectively to deposit the MCD/NCD and DLC films. A variety of characterization techniques, including filed emission scanning electron microscope (FE-SEM) and Raman spectroscopy are employed to investigate the surface morphology and atomic bonding state of as-deposited MCD/DLC and NCD/DLC composite film. The results show that both MCD/DLC and NCD/DLC composite films present similar surface morphology with the MCD and NCD films, except for scattering a considerable amount of small-sized diamond crystallites among the grain boundary area. The atomic-bonding state of as-deposited MCD/DLC and NCD/DLC composite films is determined by the top-layered DLC film, which is mainly consisted of amorphous carbon phase and no discernible sp3 characteristic peak can be observed from their Raman spectrum. Furthermore, the tribological properties of as-deposited MCD/DLC and NCD/DLC composite films is examined using a ball-on-plate reciprocating friction tester under both dry sliding and water-lubricating conditions, comparing with conventional DLC, MCD and NCD films. Silicon nitride balls are used as counterpart materials. For the CVD diamond/DLC composite films, the self-lubricating effect of top-layered DLC film is beneficial for suppressing the initial friction peak, as well as shortening the run-in period. The average friction coefficients of MCD/DLC and NCD/DLC composite films during stable sliding period are 0.07 and 0.10 respectively in dry sliding; while under water-lubricating condition, they further decreases to 0.03 and 0.07.

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Tribological Properties of Polytetrafluoroethylene Improved by Incorporation of Fluorinated Graphene with Various Fluorine/Carbon Ratios Under Dry Sliding Condition

Tribology Letters ◽

10.1007/s11249-020-01398-3 ◽

2021 ◽

Vol 69 (1) ◽

Author(s):

Lifen Liang ◽

Laizhou Song ◽

Yulin Yang ◽

Fei Li ◽

Yalong Ma

Keyword(s):

Tribological Properties ◽

Dry Sliding ◽

Fluorinated Graphene

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Tribological properties of brake friction materials with steel fibers

Metals and Materials International ◽

10.1007/s12540-009-0027-6 ◽

2009 ◽

Vol 15 (1) ◽

pp. 27-32 ◽

Cited By ~ 24

Author(s):

Sung Bin Park ◽

Keun Hyung Cho ◽

Sola Jung ◽

Ho Jang

Keyword(s):

Tribological Properties ◽

Steel Fibers ◽

Friction Materials

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Influence of the particle size on the physical, mechanical and tribological properties of composites for brake pads

10.36652/0042-4633-2021-5-36-40 ◽

2021 ◽

pp. 36-40

Author(s):

F.F. Yusubov

Keyword(s):

Particle Size ◽

Composite Materials ◽

Tribological Properties ◽

Friction And Wear ◽

Phenol Formaldehyde ◽

Environmentally Friendly ◽

Brake Pads ◽

Mechanical And Tribological Properties ◽

Pin On Disk ◽

Properties Of Composites

Tribotechnical indicators of environmentally friendly frictional composite materials with phenol-formaldehyde matrix are studied. Friction tests were carried out on a MMW-1 vertical tribometer according to the pin-on-disk scheme. Keywords: brake pads, composites, friction and wear, plasticizers, degradation, porosity. [email protected]

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Dry-Sliding Tribological Properties of TiAl/Ti2AlC Composites

Tribology Letters ◽

10.1007/s11249-013-0284-x ◽

2013 ◽

Vol 53 (2) ◽

pp. 457-467 ◽

Cited By ~ 18

Author(s):

Jun Cheng ◽

Fei Li ◽

Licai Fu ◽

Zhuhui Qiao ◽

Jun Yang ◽

...

Keyword(s):

Tribological Properties ◽

Dry Sliding

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Dry-Sliding Tribological Properties of Bronze–Graphite Composites

Tribology Letters ◽

10.1007/s11249-012-0007-8 ◽

2012 ◽

Vol 48 (2) ◽

pp. 111-122 ◽

Cited By ~ 25

Author(s):

Gongjun Cui ◽

Muye Niu ◽

Shengyu Zhu ◽

Jun Yang ◽

Qinling Bi

Keyword(s):

Tribological Properties ◽

Dry Sliding ◽

Graphite Composites

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Tribological Properties of Friction Materials Developed from Non- Asbestos Materials using Response Surface Methodology

International Journal of Engineering Materials and Manufacture ◽

10.26776/ijemm.05.02.2020.02 ◽

2020 ◽

Vol 5 (2) ◽

pp. 40-49

Author(s):

Joseph Abutu ◽

S.A. Lawal ◽

M.B. Ndaliman ◽

R. A. Lafia-Araga ◽

M. A. Oluleye

Keyword(s):

Response Surface Methodology ◽

Tribological Properties ◽

Grey Relational Analysis ◽

Coconut Shell ◽

Brake Pad ◽

Brake Pads ◽

Relational Analysis ◽

Reinforcement Material ◽

Response Performance ◽

Grey Relational

Over many years, asbestos has been used as reinforcement material in the production of brake pads production but it has lost favour due to its carcinogenic nature, as a result, there is need to investigate other possible substitute which can offer similar tribological properties as the carcinogenic material (asbestos). Several works has been carried out using different reinforcement material with the aim of finding a possible replacement for asbestos. In this work, Rule of mixture (ROM) was ustlised for sample formulation and the tribological properties of natural based material (coconut shell and seashell) were investigated using experimental design (response surface methodology) and multi-response optimisation technique (Grey relational analysis). The multi-response performance of the formulated brake pads samples was compared with a commercial brake pad sample. The research findings revealed that sample can be produced using 52% reinforcement, 35% binder, 8% abrasive and 5% friction modifier while the Grey relational analysis (GRA) showed that optimum multi-response performance of the developed coconut shell based sample can be achieved using MP, MT and CT and HTT of 12MPa, 100 oC, 6mins and 2hrs respectively while that of the developed seashell based brake pad can be achieved using MP, MT and CT and HTT of 10MPa, 160 oC, 12mins and 2hrs respectively. Also, the Analysis of variance (ANOVA) results show a percentage error of less than 5% indicating minima noise effect. In addition, the optimized coconut shell-based brake pads falls within the category of class H (µ >0.55) type of brake pads while seashell based sample falls within the class G (µ: 0.45-0.55) type of brake pads. It therefore concluded that the use of coconut shell can serve as a better substitute for asbestos-based brake pads.

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