The corrosion behaviour of different zirconium based alloys has been studied at various steam
pressures. The objectives of this work were to understand and explain the effect of alloying elements
and steam pressure on the corrosion resistance. The precipitate free alloys, like “pure” Zr and the
binary alloy Zr-1.15%Sn, show catastrophic corrosion rates at high pressure while their behaviour at
low steam pressure is similar to that of Zy4, which is almost insensitive to pressure change. As already
observed, the corrosion rate of Zr-xNb alloys depends on the niobium concentration in the alloy. All
these experimental facts are discussed from a kinetic point of view.