Effects of Hydrogen-Ion Irritation on the Microstructure and Hardness of Fe-0.2wt.%V Alloy

Microstructural and hardening changes of Fe-0.2wt.%V alloy and pure Fe irradiated with 100 keV hydrogen ions at room temperature were investigated. It was found that dislocation density varies dramatically after irradiation, ranging from dislocation free to dense areas with tangled and complex dislocation configuration. As the irradiated Fe-0.2wt.%V samples were annealed at 773 K, the irradiation-induced dislocation loops disappear, while many small precipitates with enriched C distribute in the matrix. Some large precipitates with enriched V were also observed. The hardness of Fe-0.2wt.%V alloy and pure Fe increases after irradiation, which ascribes to the formation of dislocation loops in the irradiated specimens. Compared with pure Fe, the size of the irradiation-introduced dislocation loops in Fe-0.2wt.%V alloy decreases and the density increases, the change of the hardness also decreases.

Authors:

• Jing Zhang
• Yongqin Chang
• Yongwei Wang
• Xiaolin Li
• Shaoning Jiang
• Farong Wan
• Yi Long

Keywords:

• Irradiation
• Fe-0.2wt.%V alloy
• microstructures
• hardness.

References:

[1] C. Dethloff, E. Gaganidze, V.V. Svetukhin, J. Aktaa, “Modeling of
helium bubble nucleation and growth in neutron irradiated boron doped
RAFM steels,” J. Nucl. Mater., vol. 426, pp. 287-297, July 2012.
[2] W.B. Liu, C. Zhang, Z.G. Yang, Z.X. Xia, G.H. Gao, Y.Q. Weng, “Effect
of surface nanocrystallization on microstructure and thermal stability of
reduced activation steel,” Acta Metallurgica Sinica, vol. 49, pp. 707-716,
Jun. 2013.
[3] Z. Jiao, N. Ham, G.S. Was, “Microstructure of helium-implanted and
proton-irradiated T91 ferritic/martensitic steel,” J. Nucl. Mater. vol. 367,
pp. 440-445, Aug. 2007.
[4] I.I. Chernov, S.Y. Binyukov, B.A. Kalin, M. Win,T.Swe, S.V. Chubarov,
A.N. Kalashnikov, A.G. Ioltukhovskiy, M.V. Leontyeva-Smirnova,
“Behavior of helium in steel 16Cr12W2VTaB under various implantation
temperatures,” J. Nucl. Mater., vol. 367, pp. 468-472, Aug. 2007.
[5] H. Ogiwara, A. Kohyama, H. Tanigawa, H. Sakasegawa, “Helium effects
on mechanical properties and microstructure of high fluence
ion-irradiated RAFM steel,” J. Nucl. Mater., vol. 367, pp. 428-433, Aug.
2007.
[6] C. Liu, H. Klein, P. Jung, “Embrittlement of RAFM EUROFER97 by
implanted hydrogen,” J. Nucl. Mater., vol. 335, pp. 77-82, Oct. 2004.
[7] T. Hino, Y. Katada, Y. Yamauchi, M. Akiba, S. Suzuki, T. Ezato,
“Deuterium retention of ferritic steel irradiated by energetic hydrogen
ions,” J. Nucl. Mater., vol. 386-388, pp. 736-739, Apr. 2009.
[8] Y.N. Huang, F.R. Wan, X. Xiao, S. Shi, Y. Long, S. Ohnuki, N.
Hashimoto, “The effect of isotope on the interaction between hydrogen
and irradiation defect in pure iron,” Fusion Eng. Des., Vol. 85, pp.
2203-2206, Sept. 2010. [9] F. Zhao, F.R. Wan, “Microstructure change of reduced activation
Ferritic/Martensitic steels after ion irradiation,” J. Nanjing University, vol.
45, pp. 258-263, Apr. 2009.
[10] M. PapaRao, V.S. Sarma, S. Sankaran, “Development of high strength
and ductile ultra-fine grained dual phase steel with nano sized carbide
precipitates in a V-Nb microalloyed steel,” Mater. Sci. Eng. A, vol. 568,
pp. 171-175, Jan. 2013.
[11] M. Ando, H. Tanigawa, S. Jitsukawa, T. Sawai, Y. Katoh, A. Kohyama,
K. Nakamura, H. Takeuchi, “Evaluation of hardening behaviour of ion
irradiated reduced activation ferritic/martensitic steels by an
ultra-micro-indentation technique,” J. Nucl. Mater., Vol. 307-311, pp.
260-265, Dec. 2002.