Authors

Abstract

An experimental procedure has been fully formulated and carried out to
prepare composite material of an aluminum (alloy 7020) matrix reinforced by Al2O3 particles with weight percentages of 5%, 7% and 10% and its particle size of (+53-75)μm using molten metal atomization technique. These experiments involve the preparation of aluminum matrix composite (AMCS) materials and study their Corrosion resistance in 3.5% solution of NaCl at temperature degrees 30˚C, 38˚C and 45˚C using various testing techniques. These include electrochemical corrosion and optical microscopy .
The corrosion rate was found to increase as the temperature was nominally raised from 30˚C to 38˚C and 45˚C for the 10%wt of alumina in atomized AMCS samples in 3.5% NaCl solution. At a temperature of 30˚C the corrosion rate was found to rise with increasing percentages of Al2O3 particles for 5%, 7% and 10% atomized samples. This is due to galvanic corrosion between the matrix and the second phases (MgAl2O4) and (MgO) in microstructure of AMCS. Optical microscope showed a profound appearance of general corrosion in all microstructural area and grain boundaries.

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