Influence of Acidic and Salt Media on The Corrosion Behavior of
Aluminum Matrix Composites Reinforced by Al2O3 Particles |
Corrosion behavior of pure Al and Al/ Al2O3 composite with five
weight percent of Al2O3 particles (5,10,15,20 and 25) were
investigated in 0.1M H2SO4 and 3.5 % NaCl solutions at room
temperature. The composites were prepared by powder metallurgy
and their corrosion behavior were evaluated by potentiostatic
polarization and scan rate 3mV.sec-1. It's observed that pure
Al/Al2O3 composites exhibited excellent corrosion resistance in
NaCl medium than in the H2SO4 media. The pure aluminum exhibited
slightly superior corrosion resistance than the composites in
NaCl medium but the composites had better corrosion resistance
in H2SO4 medium. Insulator Al2O3 particles are perceived to act
as inert material and degrade the integrity of the protective
oxide layer on the Al matrix. Al/Al2O3 composites have lower
corrosion rate than pure aluminum in 0.1 M H2SO4, but increasing
of wt% of alumina led to increase the corrosion rate. While in
3.5% NaCl solution can be seen that corrosion rate of pure
aluminum less than that for composites. Generlly, For certain
material, the corrosion rate in salt medium less than in acidic
medium. |
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