Study of Corrosion Behavior of Metal Matrix Composite Based on Al-Alloy (7020) Prepared by Atomization
Dr. Mukaram Shikara , Hiba Muneer Al-Khafagi , Wasnaa Hatif Mohammed

Dr. Muhammad S. Waheed , Dr. Muna K. Abbass , Ali S. Faris 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.
Keywords: Metal Matrix Composite, Atomization, Al-Alloys, Corrosion.