Skip to main content

Effects of thermal aging on Fe ion-irradiated Fe–0.6%Cu alloy investigated by positron annihilation


Thermal aging effects on surface of 2.5 MeV Fe ion-irradiated Fe–0.6%Cu alloy were investigated using positron annihilation techniques. The samples were irradiated at 573 K to a dose of 0.1 dpa. Their thermal aging was performed at 573 K for 5, 50 and 100 h. From the results of Doppler broadening measurement, an obvious trough could be seen in near-surface region from the S parameters and inflection point form at SW curves. This indicates changes in the annihilation mechanism of positrons in surface region after thermal aging. Coincident Doppler broadening indicates that the density of Cu precipitates in the thermal aged samples decreased, due to recovery of the vacancies.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3


  1. 1.

    F. Soisson, C. Fu, Cu-precipitation kinetics in α-Fe from atomistic simulations: vacancy-trapping effects and Cu-cluster mobility. Phys. Rev. B 76, 214102 (2007). doi:10.1103/PhysRevB.76.214102

    Article  Google Scholar 

  2. 2.

    S.I. Golubov, Y.N. Osesky, A. Serra et al., The evolution of copper precipitates in binary Fe–Cu alloys during ageing and irradiation. J. Nucl. Mater. 226, 252–255 (1995). doi:10.1016/0022-3115(95)00088-7

    Article  Google Scholar 

  3. 3.

    G.J. Ackland, D.J. Bacon, A.F. Calder et al., Computer simulation of point defect properties in dilute Fe–Cu alloy using a many-body interatomic potential. Philos. Mag. A 75, 713–732 (1997). doi:10.1080/01418619708207198

    Article  Google Scholar 

  4. 4.

    M. Lambrecht, A. Almazouzi, Positron annihilation study of neutron irradiated model alloys and of a reactor pressure vessel steel. J. Nucl. Mater. 385, 334–338 (2009). doi:10.1016/j.jnucmat.2008.12.020

    Article  Google Scholar 

  5. 5.

    Y. Nagai, Z. Tang, M. Hassegawa et al., Irradiation-induced Cu aggregations in Fe: an origin of embrittlement of reactor pressure vessel steels. Phys. Rev. B 63, 134110 (2001). doi:10.1103/PhysRevB.63.134110

    Article  Google Scholar 

  6. 6.

    J.Z. Liu, A. Walle, G.F. Ghosh et al., Structure, energetics, and mechanical stability of Fe–Cu bcc alloys from first-principles calculations. Phys. Rev. B 72, 144109 (2005). doi:10.1103/PhysRevB.72.144109

    Article  Google Scholar 

  7. 7.

    D. Molnar, P. Binkele, S. Hocker et al., Atomistic multiscale simulations on the anisotropic tensile behavior of copper-alloyed alpha-iron at different states of thermal ageing. Philos. Mag. 92, 586–607 (2012). doi:10.1080/14786435.2011.630690

    Article  Google Scholar 

  8. 8.

    B. Minov, M. Lambrecht, D. Terentyev et al., Structure of nanoscale copper precipitates in neutron-irradiated Fe–Cu–C alloys. Phys. Rev. B 85, 024202 (2012). doi:10.1103/PhysRevB.85.024202

    Article  Google Scholar 

  9. 9.

    G.R. Odette, On the dominant mechanism of irradiation embrittlement of reactor pressure vessel steels. Scr. Metall. 17, 1183 (1983). doi:10.1016/0036-9748(83)90280-6

    Article  Google Scholar 

  10. 10.

    T. Ishizaki, T. Yoshiie, K. Sato et al., Precipitation of Cu in Fe–Cu alloys by high-speed deformation. Mater. Sci. Eng. A 350, 102–107 (2003). doi:10.1016/S0921-5093(02)00706-2

    Article  Google Scholar 

  11. 11.

    Y. Nagai, K. Takadate, Z. Tang et al., Positron annihilation study of vacancy-solute complex evolution in Fe-based alloys. Phys. Rev. B 67, 224202 (2003). doi:10.1103/PhysRevB.67.224202

    Article  Google Scholar 

  12. 12.

    R.G. Carter, N. Sonedab, K. Dohib et al., Microstructural characterization of irradiation-induced Cu-enriched clusters in reactor pressure vessel steels. J. Nucl. Mater. 298, 211–224 (2001). doi:10.1016/S0022-3115(01)00659-6

    Article  Google Scholar 

  13. 13.

    Z. Chen, N. Kioussis, N. Ghoniem, Influence of nanoscale Cu precipitates in α-Fe on dislocation core structure and strengthening. Phys. Rev. B 80, 184104 (2009). doi:10.1103/PhysRevB.80.184104

    Article  Google Scholar 

  14. 14.

    K. Morita, S. Ishino, T. Tobita et al., Use of high energy ions for the mechanistic study of irradiation embrittlement in pressure vessel steels using Fe–Cu model alloys. J. Nucl. Mater. 304, 153–160 (2002). doi:10.1016/S0022-3115(02)00877-2

    Article  Google Scholar 

  15. 15.

    X.Z. Cao, P. Zhang, Q. Xu et al., Cu precipitates in Fe ion irradiated Fe–Cu alloys studied using positron techniques. J. Phys. C 443, 012017 (2013). doi:10.1088/1742-6596/443/1/012017

    Google Scholar 

  16. 16.

    H.B. Wu, X.Z. Cao, G.D. Cheng, et al., Effects of copper precipitates on microdefects in deformed Fe–1.5 wt%Cu alloy. Phys. Status. Solidi. A 210, 1758–1761 (2013). doi:10.1002/pssa.201228849

  17. 17.

    J.A. Baker, P.G. Coleman, Measurement of coefficients for the back-scattering of 0.5–30 keV positrons from metallic surfaces. J. Phys. C 21, L875–L880 (1988). doi:10.1088/0022-3719/21/23/003

    Article  Google Scholar 

  18. 18.

    A.P. Knights, P.G. Coleman, The observation of structure in the dependence of the 1 keV positron backscattering coefficient on target atomic number. J. Phys.: C Matter. 7, 3485–3492 (1995). doi:10.1088/0953-8984/7/18/012

    Google Scholar 

  19. 19.

    Y. Nagai, M. Hasegawa, Z. Tang, et al., Positron confinement in ultrafine embedded particles: quantum-dot-like state in an Fe–Cu alloy. Phys. Rev. B 61, 6574 (1999). doi:10.1103/PhysRevB.61.6574

    Article  Google Scholar 

  20. 20.

    Q.L. Wang, J.Z. Zhao, A model describing the microstructure evolution in Fe–Cu alloys during thermal aging. Mater. Sci. Eng. A 528, 268–272 (2010). doi:10.1016/j.msea.2010.09.012

    Article  Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Xing-Zhong Cao.

Additional information

This work was supported by the National Natural Science Foundation of China (Nos. 91026006, 91226103, 11475193, 11475197, 11575205 and 11505192) and Beijing Natural Science Foundation (No. 1164017).

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Hu, YC., Cao, XZ., Zhang, P. et al. Effects of thermal aging on Fe ion-irradiated Fe–0.6%Cu alloy investigated by positron annihilation. NUCL SCI TECH 28, 16 (2017).

Download citation


  • Fe–Cu alloy
  • Positron annihilation
  • Irradiation
  • Thermal aging