Environmentally assisted cracking in Light Water Reactors: Semiannual report, October 1994--March 1995. Volume 20

Chung, H.M.; Chopra, O.K.; Gavenda, D. J.; Hins, A.G.; Kassner, T.F.; Ruther, W.E.; Shack, W. J.; Soppet, W.K.

doi:10.2172/205937

Cited by 2 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fluorine analyses by AES were conducted on specimens from BWR-irradiated components: the experimental methods were similar to those reported earlier. [55][56][57] The specimens were obtained from HP-and CP-grade '&pe 304 SS neutron-absorber tubes and a control-blade sheath discharged from several BWRS after irradiation up to 2.6 x 1021 ncm-2 (E > 1 MeV). Expanding-mandrel tube specimens of irradiated Type 348 SS were also analyzed by AES.…”

Section: Irradiation-assisted Scc Of Austenitic Stainless Steelsmentioning

confidence: 99%

Environmentally assisted cracking in light water reactors.

Chopra¹,

Chung²,

Clark³

et al. 2007

View full text Add to dashboard Cite

The following documents In the NUREG series are available for purchase from the Government Printing Office:formal NRC staff and contractor reports, NRC-sponsored conference proceedings, international agreement reports, grantee reports, and NRC booklets and brochures. Also available a r e regulatory guides, NRC regula- Fatigue tests were conducted on ferritic steels in water that contained various concentrations of dissolved oxygen (DO) to determine whether a slow strain rate applied during different portions of a tensileloading cycle are equally effective in decreasing fatigue life. Crack-growth-rate tests were conducted on compact-tension specimens from several heats of Alloys 600 and 690 in simulated LWR environments. Effects of fluoride-ion contamination on susceptibility to intergranular cracking of high-and commercial-purity Type 304 SS specimens from controlblade absorber tubes irradiated in boiling water reactors were determined in slow-strain-ratetensile tests at 288OC. Microchemical changes in the specimens were studied by Auger electron spectroscopy and scanning electron microscopy to determine whether trace impurity elements may contribute to IASCC of these materials.

show abstract

Section: Irradiation-assisted Scc Of Austenitic Stainless Steelsmentioning

confidence: 99%

Environmentally assisted cracking in light water reactors.

Chopra¹,

Chung²,

Clark³

et al. 2007

View full text Add to dashboard Cite

show abstract

“…Higher 0 levels in steels have been also implicated to higher susceptibility to IASCC. [1][2][3] In view of this, the partitioning behavior of S , F, and 0 in MnS-type precipitates in unirradiated and irradiated steels was examined by Auger electron spectroscopy (AES), which is sensitive to these nonmetallic elements. A consequence of irradiation-induced destabilization of MnS precipitates would be the release of S and other deleterious elements back into the alloy matrix where they could diffuse, perhaps in a radiation-enhanced manner, to grain boundaries.…”

Section: Introductionmentioning

confidence: 99%

Radiation-Induced Instability of MnS Precipitates and its Possible Consequences on Irradiation-Induced Stress Corrosion Cracking of Austenitic Stainless Steels

Chung

Sanecki

Garner

1999

Effects of Radiation on Materials: 18th International Symposium

View full text Add to dashboard Cite

Irradiation-assisted stress corrosion cracking (IASCC) is a significant materials issue for the light water reactor (LWR) industry and may also pose a problem for fusion power reactors that will use water as coolant. A new metallurgical process is proposed that involves the radiation-induced release into solution of minor impurity elements not usually thought to participate in IASCC. MnS-type precipitates, which contain most of the sulfur in stainless steels, are thought to be unstable under irradiation. First, Mn transmutes strongly to Fe in thermalized neutron spectra. Second, cascadeinduced disordering and the inverse Kirkendall effect operating at the incoherent interfaces of MnS precipitates are thought to act as a pump to export Mn from the precipitate into the alloy matrix. Both of these processes will most likely allow sulfur, which is known to exert a deleterious influence on intergranular cracking, to re-enter the matrix. To test this hypothesis, compositions of MnS-type precipitates contained in several unirradiated and irradiated heats of Type 304, 316, and 348 stainless steels (SSs) were analyzed by Auger electron spectroscopy. Evidence is presented that shows a progressive compositional modification of MnS precipitates as exposure to neutrons increases in boiling water reactors. A s the fluence increases, the Mn level in MnS decreases, whereas the Fe level increases. The S level also decreases relative to the combined level of Mn and Fe. MnS precipitates were also found to be a reservoir of other deleterious impurities such as F and 0, which could be also released due to radiation-induced instability of the precipitates.

show abstract

Environmentally assisted cracking in Light Water Reactors: Semiannual report, October 1994--March 1995. Volume 20

Cited by 2 publications

References 0 publications

Environmentally assisted cracking in light water reactors.

Environmentally assisted cracking in light water reactors.

Radiation-Induced Instability of MnS Precipitates and its Possible Consequences on Irradiation-Induced Stress Corrosion Cracking of Austenitic Stainless Steels

Contact Info

Product

Resources

About