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Stress Corrosion Cracking Behavior of Alloy 718 Subjected to Various Thermal Mechanical Treatments in Primary Water

  • Mi WangEmail author
  • Miao Song
  • Gary S. Was
  • L. Nelson
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)

Abstract

Alloy 718 is an age hardenable, nickel-base alloy used in fuel assembly of Pressurized Water Reactors (PWRs) by virtue of its high strength and resistance to corrosion and stress corrosion cracking (SCC). SCC susceptibility is affected by the microstructure developed during thermal mechanical treatments. The SCC behavior of alloy 718 in three different thermal mechanical treatments (TMTs) and two different heats was studied in PWR primary water environment using constant extension rate tensile (CERT) tests. TMTs have a significant effect on the microstructure and thus the mechanical behavior and the SCC susceptibility of alloy 718. TMTs using a solution anneal at 1093 °C with a two-step ageing treatment (1093 °C/1 h + 718 °C/8 h + 621 °C/8 h) exhibited the best SCC resistance.

Keywords

Alloy 718 Stress corrosion cracking Microstructure Mechanical properties Primary water 

Notes

Acknowledgements

Support for this work was provided by the Electric Power Research Institute (contract no: MA10001593). The authors gratefully acknowledge the facilities provided by the High Temperature Corrosion Laboratory at the University of Michigan. The authors would also like to thank Dr. Chinthaka Silva from the Oak Ridge National Laboratory for the microstructural characterization.

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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  1. 1.University of MichiganAnn ArborUSA
  2. 2.JLN ConsultingMills RiverUSA

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