V. Zaprianova et al., STRUCTURE, CRYSTALLIZATION AND ELECTROCHEMICAL CORROSION BEHAVIOR OF AMORPHOUS CU66TI34 ALLOY, Crystal research and technology, 33(3), 1998, pp. 425-433
The effect of thermally induced structural changes on electrochemical
corrosion behaviour of amorphous Cu66Ti34 alloy is studied using elect
rochemical potentiodynamic polarization technique in conjunction with
XRD, TEM and DTA. The heat treatment has been carried out at two tempe
ratures: 300 degrees C - where the process of structural relaxation is
only possible and 500 degrees C - where crystallization of the alloy
occurs. As model corrosive media 1N H2SO4 and 1N HNO3 solutions are us
ed. The short range order of the amorphous samples is studied with the
total pair correlation function, Some changes of the interatomic dist
ances and a tendency to increasing of the density of the amorphous str
ucture after low temperature heating are established. The crystallizat
ion leads to formation of Cu3Ti2, beta-Cu3Ti and Cu2Ti crystalline pha
ses. It has been found that structural relaxation map have a beneficia
l effect on the susceptibility of the amorphous alloy to passivation,
while crystallization lowers considerably its corrosion resistance.