Magnesium and its alloys have attracted attention for
biomedical
implant materials in dental and orthopedic applications because of
their biodegradability and similar properties to human bones. The
very high rate of degradation in the physiological systems is, however,
a major setback to their utilization. Chemical modification is one
of the approaches adopted to enhance the corrosion resistance property
of Mg and its alloys. In this work, NaOH and H
2
O
2
were used as a pretreatment procedure to improve the corrosion resistance
of the AZ31 Mg alloy in simulated body fluid (SBF). Advanced techniques
such as dynamic electrochemical impedance spectroscopy (dynamic-EIS),
atomic force microscopy, and optical profilometry were used in addition
to the classical mass loss, hydrogen evolution, EIS, and polarization
techniques to study the corrosion resistance property of the alloy
in SBF for 30 h. Results obtained show that the surface treatment
significantly enhanced the corrosion resistance property of the alloy.
From dynamic-EIS at 30 h, the charge transfer resistance of the untreated
AZ31 Mg alloy is 432.6 Ω cm
2
, whereas 822.7 and 2617.3
Ω cm
2
are recorded for NaOH- and H
2
O
2
-treated surfaces, respectively. H
2
O
2
is a better treatment reagent than NaOH. The mechanism of corrosion
of both untreated and treated samples in the studied corrosive medium
has been discussed.