Performance of non-asbestos organic brake liners for light motor vehicles

Abstract

Abstract In the present work, a measurement system has been designed and developed to measure friction and wear for two wheeler brake liners. Non-asbestos organic brake liners were evaluated regarding friction and wear by pressing against aluminum alloy brake drum. Each brake liner was subjected to four different applied loads (400, 500, 600 and 700 N) with six different braking times (2, 4, 6, 8, 10 and 12 minutes). The velocity of the brake drum was fixed at 1000 rpm for all test conditions. The drum temperature was measured by a thermocouple embedded in the brake drum and coupled with programmable logic controller (PLC) to record the temperatures of brake drum during braking. Test results obtained from the friction test were drum temperature (°C), friction coefficient (μ) and wear volume (cm3). From the test results, it was concluded that the increase of friction coefficient at the beginning of braking is due to the sharp edges such as zircon being ploughed onto the wear surfaces and also due to the increase in the contact area of the brake drum. The wear volume increased exponentially for the applied load more than 600 N and braking time more than 4 minutes. Below the applied load of 600 N, the wear volume increased linearly. The degradation of the organic components in the composition increased with temperature and this resulted in the reduction of composition bonding between the powders and structure integrity, thus increasing wear exponentially.