Our previous investigation has indicated that pure Ni, Fe and Cr
are all in active dissolution state at the corrosion potential [14].
Table 1 lists some electrochemical parameters obtained from the
potentiodynamic polarization curves of pure Ni, Fe and Cr in
molten (Li,Na,K)F at 700 8C [14]. The free corrosion current density
of Ni is 19.3 mA cm2 more than one order of magnitude lower than 261 mA cm2 for Fe and 494 mA cm2 for Cr. The dissolution
degree of metals is related to the content of the impurities. The
dissolution may be accelerated when a metal is in electrical contact
with another metal with a more positive potential in the melt, and