Effect of Neutron Energy Spectra on the Formation of the Displacement Cascade in ${\alpha}-Iron$

  • 발행 : 2003.10.01

초록

This paper describes a computational approach to the quantification of primary damage under irradiation and demonstrates the effect of neutron energy spectra on the formation of the displacement cascade. The development of displacement cascades in ${\alpha}-Iron$ has been simulated using the MOLDY code - a molecular dynamics code for simulating radiation damage. The primary knock-on atom energy, key input to the MOLDY code, was determined from the SPECTER code calculation on two neutron spectra. The two neutron spectra include; (i) neutron spectrum in the instrumented irradiation capsule of the high-flux advanced neutron application reactor (HANARO), and (ii) neutron spectrum at the inner surface of the reactor pressure vessel steel for the Younggwang nuclear power plant No.5 (YG 5). Minor differences in the normalized neutron spectra between the two spectra produce similar values of PKA energy, which are 4.7 keV for HANARO and 5.3 keV for YG 5. This similarity implies that primary damage to the components of the commercial nuclear reactors should be well simulated by irradiation in the HANARO. Moreover, the application of the MD calculations corroborates this statement by comparing cascades simulation results.

키워드

참고문헌

  1. A.F. Calder and D.J. Bacon, 'A molecular dynamics study of dynamics study of displacement cascades in $\alpha$-iron,' J. Nucl. Mater. 207, 25 (1993) https://doi.org/10.1016/0022-3115(93)90245-T
  2. W.J. Phythian, R.E. Stoller, A.J.E. Foreman, A.F. Calder and D.J. Bacon, 'A comparison of displacement cascades in copper and iron by molecular dynamics and its application to microstructural evolution,' J. Nucl. Mater. 223, 245 (1995) https://doi.org/10.1016/0022-3115(95)00022-4
  3. D.J. Bacon, A.F. Calder, F. Gao, V.G. Kapinos and S.J. Wooding, 'Computer simulation of defect production by displacement cascades in metals,' Nucl. Instr. Meth. B 102, 37 (1995) https://doi.org/10.1016/0168-583X(94)00782-9
  4. R.E. Stoller, 'Evaluation of neutron energy spectrum effects and RPV thru-wall attenuation based on molecular dynamics cascade simulations,' Nucl. Eng. Des. 195, 129 (2000) https://doi.org/10.1016/S0029-5493(99)00241-1
  5. B.D. Wirth, M.J. Caturla, T. Diaz de la Rubia, T. Khraishi and H. Zbib, 'Mechanical property degradation in irradiated materials: A multiscale modeling approach,' Nucl. Instr. and Meth. B, 180, 23 (2001) https://doi.org/10.1016/S0168-583X(01)00392-5
  6. L.R. Greenwood and R.K. Smither, 'SPECTER: Neutron damage calculations for materials irradiation,' ANL/FPP/TM-197, Argonne National Laboratiry (1985)
  7. M.W. Finnis, 'MOLDY6 - A molecular dynamics program for simulation of pure metals,' Harwell Report AERE R-13182 (1988)
  8. L.R. Greenwood, 'Neutron interactions and atomic recoil spectra,' J. Nucl. Mater. 216, 29 (1994) https://doi.org/10.1016/0022-3115(94)90004-3
  9. C. Seo, KAERI Internal Memo, HAN-RR-CR920-01-76 (2001)
  10. B. C. Lee, Private communication
  11. R. W. Hornbeck, Numerical Methods, p.199, Quantum Publishers, Inc. New York (1975)
  12. M.W. Finnis and J.E. Sinclair, 'A simple empirical N-body potential for transition metals,' Phil. Mag. A, 50, 45 (1984)
  13. M.J. Norgett, M.T. Robinson and I.M. Torrens, 'A proposed method of calculating displacement dose rates,' Nucl. Eng. Des. 33, 50 (1975) https://doi.org/10.1016/0029-5493(75)90035-7
  14. S. Jumel, C. Domian, et al., 'Simulation of Irradaition Effects in Reactor Pressure Vessel Steels: the Reactor for Virtual Experiments (REVE) Project,' J. Test. Eval. 30, 37 (2002)