Mössbauer Spectroscopy: A Method for Nanomaterials Characterization
I. BIBICU

Abstract. The corrosion product films formed on industrial Fe-C steel with a low carbon concentration, after immersion in the diluted ammoniac solutions (NH₃ solu-tions, ammonium salts solutions), have been investigated by means of ⁵⁷Fe Mössbauer spectroscopy. The amorphous Fe³⁺ oxyhydroxides are the major constituent of the cor-rosion layers. An inhibition of corrosion was found to occur in the ammoniac solutions. The NO₃- anion in a solution of 0.1 M NH₄Cl has an inhibiting effect. The inhibition ef-fect of one compound: N-ciclohexil-benzothiazole-sulphenamida (NCBSA) on the cor-rosion of carbon-steel in diluted ammonia solution was studied. All surface spectra show that there is a magnetic anisotropy on the surface of the samples.