AUTOCLAVE TESTING OF TYPE 304 STAINLESS STEEL. Task 1, Phase 2
AISI Type 304 stainless steel U-bend test specimens were subjected to corrosive water in rocker autoclaves. One sample was suspended in the vapor phase and the other sample in the water phase ef each autoclave. Water chemistry was statistically varied. Consistent test results were attained by careful control of the autoclave atmospherc. It was determined that oxygen and chlorides in the water were the only variables which contributed to the cracking of test specimens. The chloride level for cracking is dependent on test time, while the oxygen level appears to be independent of test time. Results indicate that a high oxygen level will not allow cracking at lower chloride levels, and conversely. This is in contradiction to some of the literature. The oxygen level necessary to induce cracking was found to be approximately four per cent. Test results also indicate that oxide film formation on stainless steel may be sufficient to induce stress corrosion cracking in the prescnce of chlorides, even if the environmental oxygen concentration is low. The most significant result of this work was the surprisingly high concentration of oxygen which was necessary to induce cracking. This suggests the possibility that untreated water can be used safely if adequate deaeration of the boiler is provided. Carbon steel samples were subjected to severe environmental conditions without cracking. General corrosion resistance was poor. Recommendations were made on the test environment of the miniature neat exchangers which are to be tested as a follow- up to the autoclave program. (auth)
- Research Organization:
- Martin Co., Baltimore
- NSA Number:
- NSA-12-010579
- OSTI ID:
- 4334981
- Report Number(s):
- MND-E-1322
- Country of Publication:
- United States
- Language:
- English
Similar Records
STRESS CORROSION SCREENING TESTS OF MATERIALS FOR STEAM GENERATOR TUBING IN NUCLEAR POWER PLANTS
Mitigation of stress corrosion cracking of AISI 304 stainless steel in oxygenated water at 289 degree C by organic species at low concentration