PURPOSE: To improve external corrosion resistance and abrasion resistance by constituting a surface layer having a thickness of 10-25% of the entire thickness of a fuel coating wall with a zirconium base alloy containing, in a specified weight ratio, tin, iron, oxygen and niobium or vanadium.
CONSTITUTION: A fuel assembly rod far a reactor contains a nuclear fuel material in a fuel coating which contains an internal pipe-like layer and a surface layer, different from each other, of a zirconium allay. Relating to the rod, its surface layer has a thickness of 10-25% of the entire thickness of a fuel coating wall, and constructed of a zirconium base allay comprising tin by 0.35-0.65%, in weight ratio, iron by 0.20-0.65%, oxygen by 0.09-0.162 and niobium by 0.35-0.65% or vanadium by 0.25-0.35%, and, zirconium, separately from an unavoidable impurities, for the remaining portion.
DANIERU SHIYARUKU
MARUKU PERE
JIYAN SENEBUA
FRAMATOME SA (FR)
COGEMA (FR)
CEZUS CO EUROP ZIRCONIUM (FR)