OBSERVATIONS AND IMPLICATIONS OF INTERGRANULAR STRESS CORROSION CRACK GROWTH OF ALLOY 152 WELD METALS IN SIMULATED PWR PRIMARY WATER

Conference · Thu Aug 15 04:00:00 EDT 2013

OSTI ID:1237830

Toloczko, Mychailo B.; Olszta, Matthew J.; Overman, Nicole R.; Bruemmer, Stephen M.

Significant intergranular (IG) crack growth during stress corrosion cracking (SCC) tests has been documented during tests in simulated PWR primary water on two alloy 152 specimens cut from a weldment produced by ANL. The cracking morphology was observed to change from transgranular (TG) to mixed mode (up to ~60% IG) during gentle cycling and cycle + hold loading conditions. Measured crack growth rates under these conditions often suggested a moderate degree of environmental enhancement consistent with faster growth on grain boundaries. However, overall SCC propagation rates at constant stress intensity (K) or constant load were very low in all cases. Initial SCC rates up to 6x10-9 mm/s were occasionally measured, but constant K/load growth rates dropped below ~1x10-9 mm/s with time even when significant IG engagement existed. Direct comparisons were made among loading conditions, measured crack growth response and cracking morphology during each test to assess IGSCC susceptibility of the alloy 152 specimens. These results were analyzed with respect to our previous SCC crack growth rate measurements on alloy 152/52 welds.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1237830
• Report Number(s): PNNL-SA-97397; 401001060
• Country of Publication: United States
• Language: English

Related Subjects

alloy 152
SCC
stress corrosion cracking
intergranular
PWR