Fracture mechanics stress corrosion crack growth rate tests have been carried out on nickel base alloy 600, cold worked to different strength levels. The specimens were exposed to simulated PWR and BWR environments. The paper presents results on the effect of stress intensity - in particular low stress intensity - and yield strength on the stress corrosion crack growth rates. The experimental findings indicate that under the test conditions chosen and at the same temperature, stress corrosion cracks grow consistently two to three times faster in BWR than in PWR water.
Keywords: Stress corrosion cracking, crack growth rate, alloy 600, BWR, PWR.