Corrosive solutions in the aci dic tetrazol e are more and more e ncountered in industry [۱]. The importa nce of inhibitive protection in acidic solutions is increased by the fact that steels which are more s usceptible to be attacked in aggr essive media, are the commonly exposed metals in industrial environ ments. It is shown that the protective pro pertiesof
tetrazole derivatives depen d upon thei r ability to reduce co rrosion rate and are enhanced at higher electro n densities around the nitrogen atoms. Nu merous wo rks have been devoted to the corrosi on inhibiting effect of aqueous soluble
tetrazole on meta llic materia ls [۲].The effect of organic nitrogen compounds on the cor rosion behaviour of metallic materials in aggressive solutio ns has bee n well documented [ ۳–۷]. Their choice is based on their low-c ost and stabilit y as
corrosion inhibitors for metallic materia ls in acidic media. The most synthesised compo unds are th e nitrogen heterocyclic compoun ds, which are very kno wn to be e xcellent complex or chelate formingsubstances witht metals of transition series. Their adso rption is generally explained by the formation of an adher ent film on the metal surface [۷-۸]. The percentage inhibition efficiency was f ound to increase wit h increasing concentration of inhibito r to reach ۹ ۶% at ۱۰-۳ M. This compound is efficient inhibitor.In th e present w ork, we investig ate the
corrosion of
steel in ۰.۵M H۲SO۴ by som e newly synthesised
tetrazole compo unds. The effect of ad dition of
tetrazole derivatives on the
corrosion of
steel in ۰.۵M H۲SO۴ solution is studied using weight loss measurements, electrochemical pol arisation methods. This study permits to follow the evolution of the inhibitive effect of t etrazole derivatives on
steel in ۰.۵M H ۲SO۴. Polarisation measurements show that the
tetrazole act as mixed inhibitors. The cathodic curvesind icate that the reduction of proton at the
steel surface happens within a pure act ivating mechanism. We note a good agreement between gravimetric, electrochemical polarisationand method s.