Nano-abrasives in friction materials-influence on tribological properties

It was aimed to explore the potential of abrasives in nanometer size in friction materials (FMs). Hence six FMs were developed using micro and nano-abrasives of three types viz. alumina, SiC and silica (2%). The nano and micro composites were developed and characterized for various physical and chemical properties. The tribological performance was evaluated on a reduced scale prototype under various operating parameters and output parameters such as wear, mu(avg) as a function of speed and pressure, load-speed sensitivity of mu and friction stability were considered to compare the performance of nano and micro-composites (NCs and MCs). It was concluded that all performance parameters were significantly and beneficially affected due to nano-fillers. Nano-silica proved to impart highest wear resistance followed by SiC and then alumina while best combination of friction properties was exhibited by composites with SiC followed by Alumina and then silica. SEM on worn surfaces of pads and discs was done to understand wear mechanism and it was clearly observed that thin coherent film on both the surfaces in case of NCs was responsible for enhanced performance. (C) 2012 Elsevier B.V. All rights reserved.