Wear residues of aramid fibre formation in friction materials

Abstract

Friction and wear characteristics of aramid fibres in the automotive friction material are investigated using a pad on disc type friction tester. By means of SEM and X-ray analysis, the melting aramid fibre and its residues are detected and observed on the rubbing surfaces and lateral surfaces. The aramid fibres suffer the chemical and physical changes due to severe heating induced during braking. When the temperature of the rubbing surfaces of aramid fibres reaches or exceeds the melting point, the fibres on the surface move in the melting state. The melting particles of aramid fibres act as an interface lubricant. So it does not only lead to good wear resistance of the frictional materials, but also causes the coefficient of friction to reduce. The friction and wear mechanism of aramid fibre is discussed and analysed.