The effect of contact area on velocity weakening of the friction coefficient and friction instability: A case study on brake friction materials

Jin Woo Kim; Byung Soo Joo; Ho Jang

doi:10.1016/j.triboint.2019.02.034

The effect of contact area on velocity weakening of the friction coefficient and friction instability: A case study on brake friction materials

Jin Woo Kim, Byung Soo Joo, Ho Jang

Department of Materials Science and Engineering

Research output: Contribution to journal › Article › peer-review

44 Citations (Scopus)

Abstract

Newly found evidence on the negative slope of the friction-velocity curve is described in terms of the contact area on the surface of brake friction materials. The tribotests were performed using two commercial friction materials with and without steel fibers. The results showed that velocity weakening friction was pronounced in the friction materials containing steel fibers, which facilitated high pressure contact areas by the agglomeration of wear debris. The size of the high pressure contact area increased as the sliding velocity decreased, which supported the correlation among velocity weakening friction, friction instability, and high pressure contact areas. The pronounced velocity dependence of the friction coefficient due to transient contact area was highly relevant to noise propensity of the friction material.

Original language	English
Pages (from-to)	38-45
Number of pages	8
Journal	Tribology International
Volume	135
DOIs	https://doi.org/10.1016/j.triboint.2019.02.034
Publication status	Published - 2019 Jul

Keywords

Brake
Stick-slip
Surface topography
Wear particles

ASJC Scopus subject areas

Mechanics of Materials
Mechanical Engineering
Surfaces and Interfaces
Surfaces, Coatings and Films

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10.1016/j.triboint.2019.02.034

Cite this

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title = "The effect of contact area on velocity weakening of the friction coefficient and friction instability: A case study on brake friction materials",

abstract = "Newly found evidence on the negative slope of the friction-velocity curve is described in terms of the contact area on the surface of brake friction materials. The tribotests were performed using two commercial friction materials with and without steel fibers. The results showed that velocity weakening friction was pronounced in the friction materials containing steel fibers, which facilitated high pressure contact areas by the agglomeration of wear debris. The size of the high pressure contact area increased as the sliding velocity decreased, which supported the correlation among velocity weakening friction, friction instability, and high pressure contact areas. The pronounced velocity dependence of the friction coefficient due to transient contact area was highly relevant to noise propensity of the friction material.",

keywords = "Brake, Stick-slip, Surface topography, Wear particles",

author = "Kim, {Jin Woo} and Joo, {Byung Soo} and Ho Jang",

note = "Funding Information: This study was supported by the Railroad R&D Program of KORAIL (Contact number: 18RTRP-B148870-02 ). ",

year = "2019",

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doi = "10.1016/j.triboint.2019.02.034",

language = "English",

volume = "135",

pages = "38--45",

journal = "Tribology International",

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TY - JOUR

T1 - The effect of contact area on velocity weakening of the friction coefficient and friction instability

T2 - A case study on brake friction materials

AU - Kim, Jin Woo

AU - Joo, Byung Soo

AU - Jang, Ho

N1 - Funding Information: This study was supported by the Railroad R&D Program of KORAIL (Contact number: 18RTRP-B148870-02 ).

PY - 2019/7

Y1 - 2019/7

N2 - Newly found evidence on the negative slope of the friction-velocity curve is described in terms of the contact area on the surface of brake friction materials. The tribotests were performed using two commercial friction materials with and without steel fibers. The results showed that velocity weakening friction was pronounced in the friction materials containing steel fibers, which facilitated high pressure contact areas by the agglomeration of wear debris. The size of the high pressure contact area increased as the sliding velocity decreased, which supported the correlation among velocity weakening friction, friction instability, and high pressure contact areas. The pronounced velocity dependence of the friction coefficient due to transient contact area was highly relevant to noise propensity of the friction material.

AB - Newly found evidence on the negative slope of the friction-velocity curve is described in terms of the contact area on the surface of brake friction materials. The tribotests were performed using two commercial friction materials with and without steel fibers. The results showed that velocity weakening friction was pronounced in the friction materials containing steel fibers, which facilitated high pressure contact areas by the agglomeration of wear debris. The size of the high pressure contact area increased as the sliding velocity decreased, which supported the correlation among velocity weakening friction, friction instability, and high pressure contact areas. The pronounced velocity dependence of the friction coefficient due to transient contact area was highly relevant to noise propensity of the friction material.

KW - Brake

KW - Stick-slip

KW - Surface topography

KW - Wear particles

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DO - 10.1016/j.triboint.2019.02.034

M3 - Article

AN - SCOPUS:85062260410

SN - 0301-679X

VL - 135

SP - 38

EP - 45

JO - Tribology International

JF - Tribology International

ER -

The effect of contact area on velocity weakening of the friction coefficient and friction instability: A case study on brake friction materials

Abstract

Keywords

ASJC Scopus subject areas

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