STRESS-CORROSION CRACKING SUSCEPTIBILITY OF STEAM-GENERATOR TUBE MATERIALS IN AVT (ALL VOLATILE TREATMENT) CHEMISTRY CONTAMINATED WITH LEAD

Alloy 600 steam generator tubing has shown a high susceptibility to st ress corrosion degradation at the operation conditions of pressurized water reactors. Several contaminants, such as lead, have been postulat ed as being responsible for producing the secondary side stress corros ion cracking that has occurred mainly at the location where these cont aminants can concentrate. An extensive experimental work has been carr ied out in order to better understand the effects of lead on the stres s corrosion cracking susceptibility of steam generator tube materials, namely Alloys 600, 690 and 800. This paper presents the experimental work conducted with a view to determining the influence of lead oxide concentration in AVT (all volatile treatment) conditions on the stress corrosion resistance of nickel alloys used in the fabrication of stea m generator tubing.