Controlling the Hardness and Tribological Behaviour of Non-asbestos Brake Lining Materials for Automobiles

  • Mathur, R.B. (Carbon Technology Unit, Division of Engineering Materials, National Physical Laboratory) ;
  • Thiyagarajan, P. (Carbon Technology Unit, Division of Engineering Materials, National Physical Laboratory) ;
  • Dhami, T.L. (Carbon Technology Unit, Division of Engineering Materials, National Physical Laboratory)
  • Received : 2003.11.26
  • Accepted : 2004.02.13
  • Published : 2004.03.30

Abstract

In spite of unparalleled combination of essential material properties for brake linings and clutch facings, replacement for asbestos is seriously called for since it is a health hazard. Once asbestos is replaced with other material then composition and properties of brake pad changes. In certain cases hardness of the material may be high enough to affect the rotor material. In this study, hardness of the brake pad has been controlled using suitable reinforcement materials like glass, carbon and Kevlar pulp. Brake pad formulations were made using CNSL (cashew net shell liquid) modified phenolic resin as a binder, graphite or cashew dust as a friction modifier and barium sulphate, talc and wollastonite as fillers. Influence of each component on the hardness value has been studied and a proper formulation has been arrived at to obtain hardness values around 35 on Scleroscopic scale. Friction and wear properties of the respective brake pad materials have been measured on a dynamometer and their performance was evaluated.

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