Investigation of mechanical and corrosion properties of Al 7075/Redmud metal matrix composite

Abstract

Investigation in this paper is mechanical properties and corrosion properties of Al 7075 metal matrix composites. Al 7075 metal matrix composite is prepared from Al 7075 as a matrix and redmud as a reinforcement by using two step stir casting process. Volume percentage of reinforcement is varied from 0% to 15%. The experimental density of the composite material produced was calculated according to the Archimedes principle, greater than the basic matrix. Uniform distribution of the reinforcement and matrix in the composite is studied by using optical micrographs and microhardness of the composite is measured by using Vickers hardness testing machine. The microhardness of the composite was increased while the reinforcement went from 0% to 15%. The tensile strength of the composite material is raised at 5% of the reinforcement tolerance (326 MPa), which is higher than the base matrix. The Al 7075 metal matrix composites have a lower corrosion rate in a 3.5% NaCl solution than the base matrix. As the volume percentage increase in red mud, was reduced the corrosion rate of the composites.