Compared Modeling Study of Primary Water Stress Corrosion Cracking at Dissimilar Weld of Alloy 182 of Pressurized Water Nuclear Reactor According to Hydrogen Concentration
Omar F. Aly*, Miguel M. Neto*, Mônica M. A. M. Schvartzman**, and Luciana I. L. Lima***
*IPEN-Energy and Nuclear Research Institute
2242 Av. Lineu Prestes, S ao Paulo 05508-000, Brazil
**CDTN-Nuclear Technology Development Center, Belo Horizonte, Brazil
***Vallourec Research and Development-Corrosion, Belo Horizonte, Brazil
One of the main failure mechanisms of pressurized water reactors (PWR) is primary water stress corrosion cracking (PWSCC), which occurs in alloy 600 (75Ni-15Cr-9Fe) and weld metals such as alloy 182 (70Ni-14Cr-9Fe), and alloy 82 (73Ni-19Cr-2Fe). Corrosion cracking is due, for example, in reactor nozzles welded dissimilarly with alloys 182/82 between ASTM A-508 G3 steel and AISI316L stainless steel. Corrosion cracks can cause problems reducing nuclear installations safety and reliability. Hydrogen dissolved into primary water to prevent radiolysis, also may enhance PWSCC growth. This article begins from a study by Lima et al. (2011) based on experimental data from the CDTN-Brazilian Nuclear Technology Development Center, and related to a slow strain rate test (SSRT). This was prepared and used for testing welds in the laboratory, similar to the dissimilar weld in pressurizer relief nozzles operating at the Brazilian Angra Unit 1 nuclear power plant. It was simulated for tests, primary water at 325°C and 12.5 MPa containing four levels of dissolved hydrogen. Our objective in this article is to clarify, and discuss adequate modeling based on the SSRT experimental results, and to compare them with those from another database and modeling, of the PWSCC growth rate based on levels of dissolved hydrogen.
-  F. Nordmann. “PWR and BWR chemistry optimization,” Nuclear Engineering International Magazine, Global Trade Media, Dec. 2011, pp. 24-29, http://www.neimagazine.com/mboxstoryprint. asp?sc=2061618 [accessed February 2013]
-  C. Marks, M. Dumouchel, and J. Adler, “Materials Reliability Program: Technical Bases for the Chemical Mitigation of Primary Water Stress Corrosion Cracking in Pressurized Water Reactors (MRP-263 NP),” EPRI, Palo Alto, CA, USA, 2012 (1025669).
-  L. I. L. Lima, M. M. A. M. Schvartzman, M. A. D. Quinan, C. A. Figueiredo, and W. R. C. Campos, “Influence of Dissolved Hydrogen on Stress Corrosion Cracking Susceptibility of Nickel Based Weld Alloy, Alloy Steel – Properties and Use,” Dr. Eduardo Valencia Morales (Ed.), ISBN: 978-953-307-484-9, 2011, InTech, available from: http://www.intechopen.com/download/pdf/25315 [accessed May, 2015]
-  N. Totsuka, Y. Nishikawa, Y. Kaneshima, and K. Arioka, “Effect of Strain Rate on Primary Water Stress Corrosion Cracking Fracture Mode and Crack Growth Rate of Nickel Alloy and Austenitic Stainless Steel,” Corrosion Science, Nace International, Vol.61, pp. 219-229, 2005.
-  N. Totsuka, Y. Nishikawa, Y. Kaneshima, and K. Arioka, “The Effect of Strain Rate on PWSCC Fracture Mode of Alloy 600(UNS N06600) and 304 Stainless Steel (UNS S30400),” Corrosion/2003, paper n. 03538, Houston, TX: Nace, 2003.
-  G. White, J. Gorman, N. Nordmann, P. Jones, and M. Kreider, “Materials Reliability Program: Crack Growth Rates for Evaluating Primary Water Stress Corrosion Cracking (PWSCC) of Alloy 82, 182, and 132 Welds (MRP-115),” EPRI, Palo Alto, CA: 2004. 1006696.
-  B. Alexandreanu, O. K. Chopra, and W. J. Shack, “Crack Growth Rates and Metallographic Examinations of Alloy 600 and Alloy 82/182 from Field Components and Laboratory Materials Tested in PWR Environments,” USNRC/ANL: Argonne, IL, USA, 2008 (NUREG/CR-6964 and ANL-07/12).
-  FITNET MK7, “Stress Intensity Factor Solutions,” http://ocw. unican.es/ensenanzas-tecnicas/integridad-estructural/otros-recursos-1/solucionestextunderscore fittextunderscore fitnettextunderscore .pdf [accessed November 2012]
-  O. F. Aly, M. M. Neto, M. M. A. M. Schvartzman, and L. I. L. Lima, “Modeling Of Tests Of Primary Water Stress Corrosion Cracking Of Alloy 182 Of Pressurized Water Reactor According To EPRI And USNRC Recommendations,” Proc. of 68o. Congresso Anual da ABM., pp. 2267-2276, Sao Paulo, Brazil, ABM, 2013.
-  . H. Hua and R.B. Rebak “The role of hydrogen and creep in intergranular stress corrosion cracking of Alloy 600 and Alloy 690 PWR primary water environments-a review,” EICM-2 Proceedings ted by S. A. Shipilov; R.H. Jones; J.-M. Olive; R.B. Rebak (Eds.), EICM-2 – Second International Conference on Environment-Induced Cracking of Metals, The Banff Centre, Banff, Alberta, Canada, September 19-23, 2004, Proceedings Elsevier: London, 1st Edition, v.2, pp. 123-141, 2008.
-  C. Marks, M. Dumouchel, and G. White, “Materials Reliability Program: Probabilistic Assessment of Chemical Mitigation of Primary Water Stress Corrosion Cracking in Nickel-Base Alloys (MRP-307), Zinc Addition and Hydrogen Optimization to Mitigate Primary Water Stress Corrosion Cracking in Westinghouse Reactor Vessel Outlet Nozzles and Babcock & Wilcox Reactor Coolant Pump Nozzles,” EPRI, Palo Alto, CA, USA, 1022852, 2011.
-  E. Eason, “Program on Technology Innovation: A Preliminary Hybrid Model of Nickel Alloy Stress Corrosion Crack Propagation in PWR Primary Water Environments,” EPRI, Palo Alto, CA, USA, 1016546, 2008.
-  G.White, J. Gorman, N. Nordmann, P. Jones, M. Kreider, and J. Hickling, “Materials Reliability Program Crack Growth Rates for Evaluating Primary Water Stress Corrosion Cracking (PWSCC) of Alloy 82, 182, and 132 Welds,” (MRP-115-EPRI 1006696 Final Report) Dominion Engineering, Inc.: Reston, VA, USA, 2004.
-  O. F. Aly, M. Mattar Neto, M. M. A. M. Schvartzman, and L. I. L. Lima, “Modeling Study Of Primary Water Stress Corrosion Cracking At Dissimilar Weld Of Alloy 182 Of Pressurized Water Reactor According To Hydrogen Concentration,” SMiRT 22 Transactions, San Francisco, CA: SMiRT 22, 18-23 August 2013 (in press).
-  J.J. R’imoli, “A Computational Model for Intergranular Stress Corrosion Cracking Pasadena, CA, USA,” California Institute of Technology (Caltech). PhD. Thesis, 2009, http://thesis. mboxlibrary.caltech.edu/1808/3/Julian_Rimoli_Thesis.pdf [accessed May 2013]
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