• Nuclear industry
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• v.4 no.5 s.21
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• pp.32-41
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• 1984

현재 발전용 원자로의 $80\%$를 점하고 있는 경수로는 노심내의 핵연료에서 발생한 열을 물을 사용하여 노외로 보내는(수냉각)형식이기 때문에 열제거 효율상 물을 가압해서 고온에서도 액체로 사용하도록 고안되었으므로 노심용기는 압력용기(PV)로 되어 있다. 이 압력용기는 핵연료체와 같이 교환할 수 있는 소모품이 아니기 때문에 그 발전로의 정년까지 건전성을 유지하여야 한다. 다음은 이의 확보를 위해 해외에서 연구검토되고 있는 대응책들이다.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.3
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• pp.183-190
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• 2000

The purpose of this study is to evaluate the magnetic property change of the nuclear reactor vessel steel irradiated by fast neutrons using $M{\ddot{o}}ssbauer$ spectroscopy, and the effects of the defects produced by neutron irradiation on the changes using X-ray diffraction. The specimens, fabricated with the dimension of $23mm{\times}18mm{\times}70{\mu}m$, were irradiated by neutron fluence from $10^{12}n/cm^2\;to\;10^{18}n/cm^2$ at 343K. Throughout the experiments, it is understood that (1) the X-ray diffraction measurement shows that the change of crystal nature is started at the irradiation of $10^{16}n/cm^2$ and a crystal structure has been severely damaged at the irradiation over $10^{17}n/cm^2$, (2) the analysis of the $M{\ddot{o}}ssbauer$ spectra has shown that magnetic transition phenomena occur at the irradiation over $10^{17}n/cm^2$ and (3) both methods can be utilized as nondestructive test methods for the embrittlement evaluation of materials irradiated by fast neutrons.

• Journal of the Korean Society for Nondestructive Testing
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• v.19 no.6
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• pp.433-438
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• 1999

Magneto-acoustic emission (MAE) energy and hardness were measured in the reactor pressure vessel steel (SA508 Steel) for the various neutron fluence, irradiated dose up to $10^{18}n/cm^2$. The hardness was nearly a constant up to $10^{16}n/cm^2$, but it was rapidly increased with an increase of the neutron irradiation above $10^{17}n/cm^2$. It may be considered that the increase of hardness is due to the hindrance of dislocation motion induced defect clusters by irradiation. On the other hand. the MAE energy was slowly decreased as the neutron irradiation increased up to $10^{16}n/cm^2$ and it was rapidly decreased with an increase of the neutron irradiation above $10^{17}n/cm^2$. The decrease of the MAE energy may be considered as an increase of the defect clusters which is very sensitive to the $90^{\circ}$ domain wall motion. Furthermore, the change of MAE energy and hardness had nearly a linear relationship. but the change of MAE energy was more significant than the change of the hardness. Therefore, MAE may be considered as a very useful technique for the nondestructive evaluation of irradiation damage.