Siding wear and friction characteristics of Al MMC – brake pad tribo-couple

Prof. Surappa after graduating in Science from the Mysore University (1970) joined the Indian Institute of Science where he obtained B.E degree in Metallurgy (1973), followed by M.Sc (Engg.) (1976) and Ph.D. (1980) degrees.

Dr. Surappa joined (1979-81) newly started Regional Research Laboratory at Trivandrum where he led the group on the development of variety of Aluminium Matrix Composites.  During the period 1981-1987 he worked abroad (USA, U.K., and Switzerland).  He joined the Department of Metallurgy as an Assistant Professor in 1987 and became Professor in 1998. He is also Secretary for Karnataka State Council for Science and Technology and President of Bharath Gyan Vigyan Samithi, Karnataka.  He was Visiting Professor to Sir. M. Visveswaraya Chair, University of Mysore during 2003-2004.

He is the recipient of METALLURGIST OF THE YEAR AWARD for the year 1998 by the Ministry of Mines and Steels (Govt. of India) and the Indian Institute of Metals and MRSI MEDAL for the year 1997 by the Materials Research Society of India.

His interest cover all aspects of particle reinforced composites based in Aluminium and Magnesium Matrices.  He has two patents and more than one hundred research publications in the area of MMCs. 

 

Tribological behavior of aluminium matrix composite (AMC) / brake pad tribo-couple under dry sliding conditions was studied using Pin-on-Disc machine. Brake pad material was used as pins while the AMC formed the rotating disc. Series of experiments were performed to characterize the tribological nature of the tribo-couple. Load and sliding speeds were varied over a range to represent actual braking conditions in passenger cars. Effect of volume fraction and size distribution of reinforcement on wear and friction coefficient has been studied. It was observed that a heterogeneous tribo-layer was formed over the worn surfaces during the wear tests. Presence of tribo-layer was believed to cause two effects: acting as a lubricant layer and from acting as a source of wear debris. Morphology and topography of worn surfaces and debris were studied using scanning electron microscope (SEM), electron probe micro analyzer (EPMA), and X-ray diffraction (XRD) techniques. When the reinforcement in the matrix has wide size distribution, wear rate and friction coefficients are found to be higher compared to composite containing mono-size reinforcement.