摘要:
The effects of temperature on corrosion and the electrochemical behavior of Ni
82.3Cr
7Fe
3Si
4.5B
3.2 glassy alloy in HCl, H
2SO
4, and H
3PO
4 acids were studied using AC and DC techniques. Impedance data reveal that the susceptibility to localized corrosion increases with increasing temperature. Potentiodynamic polarization curves reveal that the bulk glassy alloy is spontaneously passivated at all the investigated temperature in H
2SO
4 and H
3PO
4 solutions. A localized corrosion effect in HCl solution is clearly observed. The apparent activation energies in the regions of Tafel, active, and passive, as well as the enthalpies and entropies of the dissolution process were determined and discussed. The high apparent activation energy (
Ea) value for H
3PO
4 solution in Tafel region is explained by the low aggressivity of PO
43- ions.