Abstract:
Corrosion and electrochemical behavior of alloys based on plastic chromium was examined. The plastic chromium was doped by additions of (0.1 to 0.4) mass%Ru, Os, Ir, Pd ou Pt. The study was conducted in 40 % sulfuric acid at 65 ºC. At a steady-state potential the alloys were shown to retain a passive state and posses a high corrosion resistance as compared with unalloyed plastic crhromium which dissolves under identical conditions. Kinetics of anodic dissolution of alloys was studied on the application of external polarization. Within the active region of potentials the alloying cathodic additions were shown to reduce the plastic chromium dissolution rate; the inhibiting effect depends on the nature of a cathodic component and increases with a growing content of the component in the alloy. The effect of reducing the corrosion rate of the cathodically-modified chromium in the active state has been attributed to the blocking of the active centers of the crystal lattice of dissolving chromium by the atoms of a platinum group metal.
Reference:
WOLYNEC, S.;ESCALANTE, E. Relation between corrosion potential and corrosion rate of steel in NaCl stagnant solution. In: INTERNATIONAL CONGRESS ON METALLIC CORROSION, 8., 1981, Mainz, Fed.Rep. Germany. Proceedings… Frankfurt am Main: DECHEMA, 1981. v. 1, p. 99-104.
Corrosion and electrochemical behavior of alloys based on plastic chromium was examined. The plastic chromium was doped by additions of (0.1 to 0.4) mass%Ru, Os, Ir, Pd ou Pt. The study was conducted in 40 % sulfuric acid at 65 ºC. At a steady-state potential the alloys were shown to retain a passive state and posses a high corrosion resistance as compared with unalloyed plastic crhromium which dissolves under identical conditions. Kinetics of anodic dissolution of alloys was studied on the application of external polarization. Within the active region of potentials the alloying cathodic additions were shown to reduce the plastic chromium dissolution rate; the inhibiting effect depends on the nature of a cathodic component and increases with a growing content of the component in the alloy. The effect of reducing the corrosion rate of the cathodically-modified chromium in the active state has been attributed to the blocking of the active centers of the crystal lattice of dissolving chromium by the atoms of a platinum group metal.
Reference:
WOLYNEC, S.;ESCALANTE, E. Relation between corrosion potential and corrosion rate of steel in NaCl stagnant solution. In: INTERNATIONAL CONGRESS ON METALLIC CORROSION, 8., 1981, Mainz, Fed.Rep. Germany. Proceedings… Frankfurt am Main: DECHEMA, 1981. v. 1, p. 99-104.
