Effect of Neutron Irradiation on the Critical Event Size of Cleavage Fracture of the Chinese A508-3 Steel

Abstract:

In order to analyze the influence of neutron irradiation on the critical event of cleavage fracture for the Chinese A508-3 (RPV) steel, the fracture morphology, microstructure and grain size of the irradiated specimens are observed and analyzed by optical microscope (OM) and scanning electron microscope (SEM). The results show that with the increase of neutron doses, the fracture mode of Chinese RPV steel material changes gradually from ductile fracture to ductile-brittle mixed fracture transformation. The brittle part for fracture mode of ductile-brittle fracture is cleavage fracture, and the non-metallic inclusions, microstructure and grain size grades are not significantly different from those of the specimens without cleavage fracture. In the same material, with increasing of neutron doses, the critical event size of the cleavage fracture will be reduced, and the percentage of the grain that satisfies the grain size of the cleavage critical event will increase correspondingly, resulting in an increase of the probability of cleavage fracture of the material. The fine grain with uniform distribution can improve partly the fracture toughness of the material and withstand higher neutron doses under the same conditions.

• Periodical: Materials Science Forum (Volume 1060)
• Pages: 105-117
• DOI: https://doi.org/10.4028/p-285x99
• Online since: May 2022
• Authors: Fan Yang, Rong Jian Pan*, Zhen Wang, Hai Sheng Zhang
• Keywords: Cleavage Fracture, Fracture Morphology, Irradiation, Microstructure

References

[1] A. Kryukov, L. Debarberis, U. Estorff, et al., Irradiation brittlenessof reactor pressure vessel steel at very high neutron fluence, J. Nucl. Mater. 422 (2012) 173-177.

DOI: 10.1016/j.jnucmat.2011.12.026

[2] M. Wan, G. Shu, R. Wang, et al., Study of the microstructure evoluiton of A508-3 steel under proton irradiation, Acta Metallurgica Sinica, 48 (2012) 929-934. (In Chinese).

DOI: 10.3724/sp.j.1037.2012.00060

[3] W. Yang, Summary of irradiation effects for the reactor pressure vessel steel of PWR, Nuclear safety, 3 (2012) 1-11. (In Chinese).

[4] Y. Lin, C. Zhang, C. Ning, et al. Irradiation property of pressure vessel materials in China, Materials China, 05 (2011) 7-10. (In Chinese).

[5] G. Adjanor, S. Bugat, C. Domain, et al. Overview of the RPV-2 and INTERN-1 packages: From primary damage to microplasticity, J. Nucl. Mater. 406 (2010) 175-186.

DOI: 10.1016/j.jnucmat.2009.09.006

[6] L. Cao, S. Wu, B. Liu, On the Cu precipitation behavior in thermo-mechanically brittlenessprocessed low copper reactor pressure vessel model steel, Mater. Design, 47 (2013) 551–556.

DOI: 10.1016/j.matdes.2012.12.055

[7] M. Lambrecht, E. Meslin, L. Malerba, et al., On the correlation between irradiation-induced microstructural features and the hardening of reactor pressure vessel steels, J. Nucl. Mater. 406 (2010) 84-89.

DOI: 10.1016/j.jnucmat.2010.05.020

[8] P. Liu, Q. Zhan, M. Zhao, et al. Microstructure changes of reduced activition steel after deuterium ion irradiation at high temperature, Journal of Functional Materials, 23 (2014) 23070-23074.

[9] H. Huang, R. Bartrand, P. Philippe, Reactor pressure vessel steels:influence of chemical composition and neutron irradiation conditions on irradiation damage, Materials Reports, 27 (2013) 106-112. (In Chinese).

[10] R. Wang, C. Xu, P. Huang, et al., Summaries of neutron fluence rate effects on har dening and brittlenessof nuclear reactor pressure vessel steels, Science and Technology Review, 32 (2014) 80-84. (In Chinese).

[11] R. Wang, C. Xu, X. Liu, et al., Influence factors of nuclear power plant reactor pressure vessel on irradiation embirttlement, China Metallurgy, 24 (2014) 1-5. (In Chinese).

[12] P. Pareige, R.E. Stoller, K.F. Russell, et al., Atom probe characterization of the microstructure of nuclear pressure vessel surveillance materials after neutron irradiation and after annealing treatments, J. Nucl. Mater. 249 (1997) 10.

DOI: 10.1016/s0022-3115(97)00215-8

[13] L. Debarberis, B. Acosta, A. Zeman, et al., Analysis of WWER-440 and PWR RPV welds surveillance data to compare irradiation damage evolution, J. Nucl. Mater. 350 (2006) 9.

DOI: 10.1016/j.jnucmat.2006.01.003

[14] Y. Peng, W. Zhu, H. Tang, et al. Study on microscopic of RPV weld material EG-F2N steel after irradiation with inmpact adnormal data, Nuclear Power Engineering, s1 (2017) 136-139. (In Chinese).

[15] E. Smith. The nucleation and growth of cleavage microcracks in mild steel. Proceedings of Conference on Physical Basis of Yield and Fracture. London: Institute of Physics and Physical Society, (1996).

[16] J. Chen, R. Cao, Micromechanism of cleavage fracture of weld matals, Acta Metallurgica Sinica, 53 (2017) 1427-1444. (In Chinese).

[17] C. Yan, J. Chen. An investigation into the micro-criterion of cleavage fracture, Journal of Gansu University of Technology, 03 (1993) 8-13. (In Chinese).

[18] G. Wang, J. Chen, J. Wang, On the measurement and physical meaning of the cleavage fracture stress in steel, PTCA(Part A: physical testing), 10 (2002) 420-423+437. (In Chinese).

[19] J. Li, R. Cao, G. Mao, et al., Intrinsic mechanisms of ductile-brittle transition for F460 steel welding coarse grained heat affected zones with different heat inputs, Journal of Materials Engneering, 44 (2016): 70-76. (In Chinese).

[20] G. Wang, J. Wang, J. Chen, Effects of specimen sizes on the local cleavagefracture stress of steel, Journal of Mechanical Strength, 25 (2003) 552-555. (In Chinese).

[21] G. Wang , Y. Wang , F. Xuan , et al., Effects of loading rate,notch geometry and loading mode on the cleavage fracture behavior of 16mnr steeL, Acta metallurgica sinica, 45 (2009) 866-872. (In Chinese).

[22] G. Wang, J. Chen, Effects of sizes of carbide particles on fracture behavior of notched specimens, Journal of Gansu University of Technology, 1 (1997) 1-6. (In Chinese).

[23] D. Wang, X. Li, J. Wei, et al., Effect of tempering temperature on fracture toughness of high carbon steel, Journal of Iron and Steel Research, 29 (2017) 494-499. (In Chinese).

[24] J.R. Chen, R. Cao. Micromechanism of cleavage fracture of metals, Elsevier, (2014).

[25] H. Ma, J. Chen, L. Zhu, Spherical non-metallic inclusion and fractures of weld matals, Journal of Gansu University of Technology, 02 (1993) 1-6. (In Chinese).

[26] Y. Sun, Q. Yu, Cleavage fracture mechanics and micromorphology analysis of low carbon steel, Journal of Kunming University of Science and Technology (Nature Science Edition), 36 (2011) 18-22. (In Chinese).