INVESTIGADORES
VAZQUEZ marcela Vivian
artículos
Título:
Properties of the passive films present on copper and copper-nickel alloys in slightly alkaline solutions
Autor/es:
S. CERE; M. VAZQUEZ
Revista:
JOURNAL OF MATERIALS SCIENCE LETTERS
Editorial:
JOURNAL OF MATERIALS SCIENCE LETTERS
Referencias:
Año: 2002 vol. 21 p. 493 - 495
ISSN:
0261-8028
Resumen:
Combining electrochemical and spectrophometrical techniques the presence of cuprous oxide in the passive film formed on copper and copper-nickel alloys at rest potential in slightly alkaline electrolytes can be established. However, when the nickel content increases and reaches 30%, the composition of the film changes noticeably by the incorporation of Ni(II) compounds. In parallel, the film thickness, estimated from the cathodic charge of the reduction peaks in the voltammograms and the potentiodynamic curves, as well as from the absorbance of the films seems to decrease as the nickel content increases. In order to explain the beneficial effect of the Ni incorporation in the alloys regarding the corrosion resistance to aggressive environments, the charge transfer resistance should increase with the nickel content. Preliminary results of electrochemical  impedance spectroscopy support this assumption