Investigation of the protection potential against IASCC
Conference
·
OSTI ID:48129
- General Electric Co., Pleasanton, CA (United States)
- Electric Power Research Institute, Palo Alto, CA (United States)
Environmentally induced cracking of components exposed to the radiation and high-temperature aqueous environment of a light water reactor (LWR) is known as irradiation-assisted stress corrosion cracking (IASCC). In boiling water reactors (BWRs) annealed austenitic stainless steels have a threshold level of irradiation damage. Above a fluence level of 5 x 10{sup 20}n/cm{sup 2}, these alloys are susceptible to cracking in the normal BWR core environment. Below this threshold value, laboratory stress corrosion tests of irradiated material have not indicated cracking over a range of corrosion potentials. Recent electrochemical measurements in the core bypass region of several operating BWRs have indicated that the corrosion potentials of Type 304 stainless steel can be as high as 0.250 {+-} 0.025 V (SHE). The potential depends on the specific measurement location. Testing indicates that at high potentials Type 304 stainless steel irradiated above the threshold fluence suffers IASCC, but, if the potential can be decreased, the phenomenon does not occur. An effective environmental modification for eliminating cracking of sensitized Type 304 stainless steel in BWR piping systems is the addition of hydrogen to the reactor feedwater. Hydrogen injection results in a decrease in the electrochemical potential (ECP). Below -0.230 V(SHE), pipe cracking known as intergranular stress corrosion cracking (IGSCC) is effectively mitigated. The identification of a threshold potential for IGSCC was established by performing laboratory stress corrosion tests on thermally sensitized Type 304 stainless steel using the constant extension rate technique (CERT) at controlled ECPs. Similar logic was applied to the experimental program described in this paper.
- OSTI ID:
- 48129
- Report Number(s):
- CONF-910808--
- Country of Publication:
- United States
- Language:
- English
Similar Records
Pre-immersion effect on IASCC susceptibility in austenitic stainless steel
IASCC susceptibility of low-fluence stainless steels evaluated by in-flux slow strain rate tests. Final report
Effects of water chemistry on intergranular cracking of irradiated austenitic stainless steels
Book
·
Fri Sep 01 00:00:00 EDT 1995
·
OSTI ID:99569
IASCC susceptibility of low-fluence stainless steels evaluated by in-flux slow strain rate tests. Final report
Technical Report
·
Thu Aug 01 00:00:00 EDT 1996
·
OSTI ID:378909
Effects of water chemistry on intergranular cracking of irradiated austenitic stainless steels
Book
·
Sat Dec 30 23:00:00 EST 1995
·
OSTI ID:203779