Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Radiation Effects Related to Repaired BWR Core Shrouds

Journal Article · · Journal of Nuclear Materials
 [1];  [2];  [3];  [4]
  1. Carleton University
  2. Queen's University (Ontario)
  3. Georgia Institute of Technology
  4. BATTELLE (PACIFIC NW LAB)

The material properties of the core shroud and supporting tie rod components are important factors for Boiling Water Reactor (BWR) life extension considerations. Given the variability of nickel and boron content found in 304 stainless steel shroud plates, and XM-19 and Inconel X-750 tie rod materials, this paper combines the latest spectral information in the vicinity of the core shroud to calculate hydrogen and helium gas production limits as well as atomic displacement damage spanning 80 full-power years (FPY) using the SPECTER code. Results indicate that, whereas boron has little effect on the atomic displacement damage, helium production from boron can be important and must be included in weldability assessments. Since the boron concentration is uncertain, helium generation is calculated assuming a composition range based on specifications and reported measurements. The results show that helium production caused by transmutations in the 304 SS shroud material are dominated by the concentration of boron and will have a significant impact on weldability after only a few years of service. For tie rods, the susceptibility to irradiation-assisted stress corrosion cracking (IASCC) has been assessed by determining helium production in Inconel X-750 IASCC specimens irradiated in the Advanced Test Reactor (ATR) reactor and correlating with the helium produced in a BWR. As a tie rod material in a high thermal neutron flux environment, Inconel X-750 is more likely to be IASCC sensitive during service in a BWR due to helium than the XM-19 stainless steel alloy because of a greater nickel content and boron concentration. Weldability of the core shroud plate material, IASCC of the tie rod materials, and the gamma photon contribution to radiation damage are discussed.

Research Organization:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC05-76RL01830
OSTI ID:
1797392
Report Number(s):
PNNL-SA-157877
Journal Information:
Journal of Nuclear Materials, Vol. 551
Country of Publication:
United States
Language:
English

References (18)

Radiation-induced material changes and susceptibility to intergranular failure of light-water-reactor core internals journal September 1999
A review of irradiation assisted stress corrosion cracking journal August 1994
A new calculation of thermal neutron damage and helium production in nickel journal April 1983
Modelling grain boundary cavity growth in irradiated nimonic PE16 journal May 1990
Suppression of HAZ cracking during welding of helium-containing materials journal September 1992
Threshold helium concentration required to initiate cracking during welding of irradiated stainless steel journal August 1995
Hydrogen generation arising from the59Ni(n, p) reaction and its impact on fission—fusion correlations journal October 1996
Accelerated materials evaluation for nuclear applications journal May 2017
Gas Production in Reactor Materials journal January 2006
In-reactor stress relaxation of selected metals and alloys at low temperatures journal May 1980
Radiation-Induced Stress Relaxation of Welded Type 304 Stainless Steel Evaluated by Neutron Diffraction journal January 2006
Computer Simulation of Displacement Cascade Damage in Metals journal January 1994
A proposed method of calculating displacement dose rates journal August 1975
Neutron and Gamma Fluence and Radiation Damage Parameters of Ex-Core Components of Russian and German Light Water Reactors conference November 2011
The stability of precipitates in an irradiation environment journal September 1972
Computer simulation of defect production by displacement cascades in metals journal August 1995
Effects of gamma-induced displacements on HFIR pressure vessel materials journal December 1994
Neutron interactions and atomic recoil spectra journal October 1994