کلیدواژهها
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magnetron sputtering technique, pure Ta, nano-structured, electrochemical behavior, Ringer’s physiological solution
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چکیده
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Through this survey, by the application of magnetron sputtering technique, an unprecedented nanostructured (NS) α-Ta was coated on Ti substrate. The provided coating was fully dens, homogeneous
in microstructure and with crystals preferable to specific plane of (110). Employing comprehensive
electrochemical evaluations, the formed passive layer on the α-Ta coating and pure uncoated Ta in the
Ringer’s electrolyte at 37 °C were compared in various aspects including the electrochemical response,
semiconductivity, donor density (ND) and the point defects diffusivity (D0). The α-Ta coated sample
showed much higher corrosion resistance in Ringer’s electrolyte than the bare Ta. Moreover, Mott–
Schottky analysis revealed a reduced ND in the passive layer formed on the α-Ta coating compared to
that of the pure Ta. The calculated quantities of D0 for the α-Ta coating (1.06×10−17 cm2 s−1) are
more than values of the pure Ta (0.94×10−17 cm2 s−1). The enhanced corrosion resistant behavior
of α-Ta coating in the simulated body environment, compared to the pure Ta specimen, can be
attributed to the formation of nano-scale microstructure and the crystallographic texture in the coated
sample that accelerates the formation of a sturdy and ameliorated p
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