[01] Pruthviraj R. D., R&D Centre, Department of Engineering Chemistry, RajaRajeswari College of Engineering, Visvesvaraya Technological University, Bangalore, Karnataka, India.

The aim of the research work was to investigate the corrosion behaviour of Silicon Carbide(SiC) reinforced aluminium 7075 metal matrix composites (MMCs) in a mixture of alkaline and salt solution using weight loss method. The mixture alkali and salt solution used is mixture of sodium hydroxide and sodium chloride solutions. The composites are manufactured by liquid metallurgy technique using vortex method. Aluminium 7075 / SiC MMCs containing 2, 4 and 6 weight percentage of SiC particulates are casted. The corrosion characteristics of Aluminium 7075 /SiC composite and the unreinforced alloy were experimentally assessed. The corrosion test was carried out at different concentrations of mixture of sodium hydroxide and sodium chloride solution at a concentration of 0.025M, 0.05M and 0.1 M solutions for different exposure time. The results indicated that corrosion rate of metal matrix composites was lower than that of matrix material Al 7075 under the corrosive atmosphere irrespective of exposure time and concentration of corrodent. Aluminium 7075 / SiC composite become more corrosion resistant as the SiC content is increased. This is because of the formation of stable oxide layer over the specimens. Scanning Electron Microscopy (SEM) show the degree of attack of alkaline solution on the surface of the investigated material.

Metal Matrix Composite (MMCs), Silicon Carbide, Corrosion Loss, Weight Loss

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