This work involves studying the effect
of adding (50%Isopropanol – 30%Methanol – 17%Xylene) mixture on
corrosion behavior of pure Al and its alloys in simulated fuel
at room temperature. The results of electrochemical measurements
indicate that the addition of this mixture lead to decreasing in
corrosion rate values for pure Al and its alloys.
Electrochemical measurements were carried out by potentiostat at
weep rate of 3 mV/sec to estimate the corrosion parameters using
Tafel extrapolation method, in addition to cyclic polarization
test to know the pitting susceptibility of materials in tested
medium. Generally, the cathodic Tafel slope (bc) were increased
after adding mixture. But the anodic Tafel slopes (ba) were
decreased except for Al-Cu alloy. The small anodic slope
indicates the presence of a film on the surface of the tested
material, which is less permeable and can even obstruct the
metal dissolution reaction but still permits an electrochemical
reaction to occur. This behavior can be achieved by the
electronic density on oxygen atoms in alcohols. Keyword: Al and
its alloys, fuel, corrosion resistance. |