What will Titanium Metal Behavior in Aqueous Solutions
What will Titanium Metal Behavior in Aqueous Solutions?
The electrochemical response of titanium metal behavior in aqueous solutions falls somewhere between that of the true valve metals (e.g., Zr, Nb, Ta) and that of the active-passive metals (e.g., Fe, Co. Ni, Cr). In particular, its oxide film formation resembles that of valve metals, while its corrosion is similar to corrosion of active-passive metals. In defining the bounds of his review of the electrochemical behavior of titanium. In aqueous solutions, titanium displays four different types of behavior.
They are:
1 .) "active" behavior -a state in which the metal can be oxidized at a relatively high rate, forming titanium ions in solution.
2.) "passive" behavior -a state in which the metal is coved by a titanium oxide film and can be oxidized only very slowly, resulting in the production of titanium ions in solution or thickening of the film.
3.) "active-passive" behavior -a transitional state between the active and passive states in which metal oxidation is somewhat impeded by the incomplete state of the surface passivation.
4.) "hydrogen evolution" -a cathodic behavior that occurs in conjunction with active corrosion of Ti. or when Ti is polarized to sufficiently low potentials, either by an externally impressed current or through electrical contact with another actively corroding metal (i.e., galvanic coupling).
Which particular behavior is spontaneously exhibited at a given time depends on the duration of exposure, pH. temperature, solution composition, material composition, and other factors. The polarization response of titanium can be divided into four distinct regions: hydrogen evolution, active, active-to-passive transition, and passive regions.