Investigation of Dual-Beam-Implanted Oxide-Dispersed-Strengthened FeCrAl Alloy by Positron Annihilation Spectroscopy

Abstract:

Oxide-dispersion-strengthened (ODS) FeCrAl steel is a class with promising materials to be applied for future nuclear applications. However, radiation damage, especially the formation of vacancy clusters or gas-filled bubbles, may result in hardness increase and the loss of ductility. Positron annihilation spectroscopy (PAS) is demonstrated to be a very useful and non-destructive analysis method to detect and to determine open volume defects of sub-nm size in ODS alloy. Synchronized dual beam implantation of Fe and He ions is performed to simulate the radiation damage caused by (n, α) reactions and to avoid induced activation. For room temperature implantation, i.e. without significant point defect recombination, the differences in the defect formation are shown by comparison between irradiation of ODS alloy and pure Fe bulk. The open volume defects created in ODS alloy are vacancy clusters closely connected with dispersed Y oxide nanoparticles. Their profiles are in reasonable qualitative agreement with the hardness profiles, indicating a relationship between sub-nm vacancy clusters or He bubbles and the hardness of the material. In heat-treated ODS alloy, containing larger vacancy clusters, the radiation induced hardness increase is more distinctive than for as-received ODS alloy. For irradiation at a moderately enhanced temperature of 300°C open volume defects are drastically reduced. The few remaining defects are vacancy clusters of the same type as in as-received ODS alloy. Close to the surface the open volume defects completely disappear. These results are in agreement with the hardness measurements showing little hardness increase in this case. The suitability of ODS-based materials for nuclear applications was verified.

• Periodical: Defect and Diffusion Forum (Volume 331)
• Pages: 149-163
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.331.149
• Online since: September 2012
• Authors: Reinhard Kögler, Wolfgang Anwand, Asta Richter, Maik Butterling, A. Mücklich, Xin Ou, H. Reuther, Chun Liang Chen, Andreas Wagner
• Keywords: Hardness, He Bubbles, ODS Steel, Radiation Resistant Materials, Simultaneous Dual Beam Ion Implantation, Vacancy Clusters

References

[1] G.R. Odette, M.J. Alinger, B.D. Wirth, Recent developments in irradiation resistant steels, Annu. Rev. Mater. Res. 38 (2008) 471-503.

DOI: 10.1146/annurev.matsci.38.060407.130315

[2] L.K. Mansur, Theory and experimental background on dimensional changes in irradiated alloys, J. Nucl. Mater. 216 (1994) 97-123.

DOI: 10.1016/0022-3115(94)90009-4

[3] J.D. Hunn, E.H. Lee, T.S. Byun, L.K. Mansur, Effects of helium on radiation-induced defect microstructure in austenitic stainless steel, J. Nucl. Mater. 280 (2000).

DOI: 10.1016/s0022-3115(00)00038-6

[4] I. -S. Kim, J.D. Hunn, N. Nashimoto, D.L. Larson, P.J. Maziasz, K. Miyahara, E.H. Lee, Defect and void evolution in oxide dispersion strengthened ferritic steels under 3. 2 MeV Fe+ ion irradiation with simultaneous helium injection, J. Nucl. Mater. 280 (2000).

DOI: 10.1016/s0022-3115(00)00066-0

[5] T. Yamamoto, G.R. Odette, P. Miao, D.T. Hoelzer, J. Bentley, N. Hashimoto, The transport and fate of helium in nanostructured ferritic alloys at fusion relevant He/dpa ratios and dpa rates, H. Tanigawa, R.J. Kurtz, J. Nucl. Mater. 367-370 (2007).

DOI: 10.1016/j.jnucmat.2007.03.047

[6] J. Chen, P. Jung, W. Hoffelner, H. Ullmaier, Dislocation loops and bubbles in oxide dispersion strengthened ferritic steel after helium implantation under stress, Acta Materialia 56 (2008) 250-258.

DOI: 10.1016/j.actamat.2007.09.016

[7] H. Ohkubo, Z. Tang, Y. Nagai, M. Hasegawa, T. Tawara, M. Kiritani, Positron annihilation study of vacancy-type defects in high-speed deformed Ni, Cu and Fe, Mat. Sci. Engin. A350 (2003) 95-101.

DOI: 10.1016/s0921-5093(02)00705-0

[8] L.C. Damonte, M.A. Taylor, J. Desimoni, J. Runco, PALS study on the defect structure of yttria-stabilized zirconia, Radiation Physics and Chemisty 76 (2007) 248-251.

DOI: 10.1016/j.radphyschem.2006.03.046

[9] L.C. Damonte, M.C. Caracoche, D. Lamas, Positron characterization of metastable phases in yttria stabilized zirconia, phys. stat. sol. 10 (2007) 3843-3846.

DOI: 10.1002/pssc.200675841

[10] J. Xu, C.T. Liu, M.K. Miller, H. Chen, Nanocluster-associated vacancies in nanocluster-strengthened ferritic steel as seen via positron-lifetime spectroscopy, Phys. Rev. B 79 (2009) 020204-1-4.

DOI: 10.1103/physrevb.79.020204

[11] Y. Ortega, V. de Castro, M.A. Munoz, T. Leguey, R. Pareja, Positron annihilation characteristics of ODS and non-ODS EUROFER isochronally annealed, J. Nucl. Mater. 376 (2008) 222-228.

DOI: 10.1016/j.jnucmat.2008.03.005

[12] R. Rajaraman, G. Amarendra, C.S. Sundar, Defect evolution in steels: Insights from positron studies, phys. stat. sol. 6 (2009) 2285-2290.

DOI: 10.1002/pssc.200982112

[13] V. Krsjak, Z. Szaraz, P. Hähner, Positron annihilation lifetime study of oxide dispersion strengthened steels, J. Nucl. Mater. (2011) http: /dx. doi. org/10. 1016/j. jnucmat. 2011. 11. 058.

DOI: 10.1016/j.jnucmat.2011.11.058

[14] H. Kishimoto, K. Yutani, R. Kasada, A. Kimura, Helium cavity formation research on oxide dispersed strengthening ferritic steels utilizing dual-ion irradiation facility, Fusion Engineering and Design 81 (2006) 1045-1049.

DOI: 10.1016/j.fusengdes.2005.09.049

[15] C. -L. Chen, A. Richter, R. Kögler, G. Talut, Dual beam irradiation of nanostructured FeCrAl oxide dispersion strengthened steel, J. Nucl. Mater. 412 (2011) 350-358.

DOI: 10.1016/j.jnucmat.2011.03.041

[16] A. Richter, C. -L. Chen, A. Mücklich, R. Kögler, Irradiation damage in dual beam irradiated nanostructured FeCrAl oxide dispersion strengthened steel, Mater. Res. Soc. Symp. Proc. Vol. 1298 (2011) 141-146.

DOI: 10.1557/opl.2011.47

[17] R. Kögler, W. Anwand, A. Richter, M. Butterling, X. Ou, A. Wagner, C. -L. Chen, Nanoc acvity formation and hardness increase by dual ion beam irradiation of oxide disperesed strengthended FeCrAl alloy, J. Nucl. Mater. 427 (2012) 133-139.

DOI: 10.1016/j.jnucmat.2012.04.029

[18] W. Anwand, H. -R. Kissener, G. Brauer, Acta Phys. Polonica A 88 (1995) 7-11. W. Anwand et al., see this issue.

DOI: 10.12693/aphyspola.88.7

[19] P. Asoka-Kumar, M. Alatalo, V.J. Ghosh, A.C. Kruseman, B. Nielsen, K.G. Lynn, Increased elemental specifity of positron annihilation spectra, Phys. Rev. Lett. 77 (1996) 2097-2101.

DOI: 10.1103/physrevlett.77.2097

[20] A. Vehanen, P. Hautojarvi, J. Johansson, J. Yli-Kauppila, P. Moser, Vacancies and carbon impurities in α- iron: Electron irradiation, PRB 25 (1982) 762-780.

DOI: 10.1103/physrevb.25.762

[21] M.J. Puska, P. Lanki, R.M. Nieminen, Positron affinities for elemental metals, J. Phys., Condens. Matter 1 (1989) 6081-6093.

DOI: 10.1088/0953-8984/1/35/008

[22] A. Hirata, T. Fujita, Y.R. Wen, J.H. Schneibel, C.T. Liu, M.W. Chen, Atomic structure of nanoclusters in oxide-dispereion-strengthened steels, Nature Materials Letters 10 (2011) 922-926.

DOI: 10.1038/nmat3150

[23] P. Hosemann, D. Kiener, Y. Wang, S.A. Maloy, Issues to consider using nanoindentation on shallow ion beam irradiated materials, J. Nucl. Mater. 425 (2011) 136-139.

DOI: 10.1016/j.jnucmat.2011.11.070

[24] H. Bückle, The Sience of Hardness Testing and its Research Applications, ASM, Metals Park, Ohio, ed. by J.H. Westbrook and J. Conrad (1973).

[25] A. van Veen, H. Schut, J. de Vries, R.A. Haakvoort, M.R. Ijpma, Positron beams for solids and surfaces, in: P.J. Schultz, G.R. Massoumi, P.J. Simpson (Eds. ), Proceedings of the AIP Conference, Vol. 218 (1990) 171-177.