Further Observations on the Electrochemical Behavior of Ti-Ni Alloys in Acidic Chloride Solutions

Previous investigations¹  of the corrosion behavior of Ti-Ni alloys in boiling acidic chloride solutions have established that alloying with nickel increases the corrosion resistance of titanium. More recent studies by the author and co-workers²  have shown that this increased corrosion resistance results from an increase in the efficiency of the overall cathodic process which creates a mixed potential in the passive potential range for titanium. These studies²  also revealed a progressive facilitation, at ambient temperatures, of the cathodic process with increasing nickel content in the range 0 to 38 wt % nickel (i.e., Ti to Ti₂Ni), and this can be readily interpreted as indicating that the corrosion resistance of Ti-Ni alloys will increase with increasing nickel content. This interpretation is at variance with the conclusions of Murphy³  who suggested, as a result of his measurements of a certain ambient temperature parameter referred to as...