REACTION OF TELLURIUM WITH ZIRCALOY-4

Interaction of tellurium vapour with Zircaloy during the initial stage of an accident will lead to retention of tellurium in the core. For r eliable estimation of the release behaviour of tellurium, it is necess ary to know which zirconium tellurides are formed during this interact ion. In this work the reaction of tellurium with Zircaloy-4 has been s tudied, using various reaction temperatures and tellurium vapour press ures. The compound Zr1+xTe2 is formed on the surface of the Zircaloy i n a broad range of reaction temperatures and vapour pressures. It is f ound that the formation of the more zirconium-rich compound Zr5Te4 is favoured at high reaction temperatures in combination with low telluri um vapour pressures.