|
Vol.42, No.1, 75 ~ 82, 2004
|
| Title |
| Effect of Internal Pressure on the Corrosion Behavior of Zr Nuclear Fuel Cladding Tubes |
| 박정용 Park Jeong Yong , 김선기 Kim Seon Gi , 정용환 Jeong Yong Hwan , 정연호 Jeong Yeon Ho |
|
|
|
| Abstract |
| Effect of the internal pressure on the corrosion behavior was investigated for the Zr nuclear fuel cladding tubes which were pressurized up to 2500 psi using Ar gas and corroded in steam of 1500 psi at 400℃. It was found that corrosion resistance of Zr fuel cladding tube was decreased with increasing the internal pressure although corrosion behavior at the early stage was similar irrespective of internal pressure. X-ray diffraction result on the oxide showed that crystal structure was not affected by the applied pressure of 2500 psi. SEM observation on the oxide surface revealed that a number of cracks elongated in axial direction were propagated from surface to interior in the case of 2500 psi. The degradation of corrosion resistance with internal pressure was attributable to the extensive cracking at the oxide surface, which is thought to be originated from the difference of ductility between Zr alloy and oxide when Zr fuel cladding tube was deformed due to the applied internal pressure. However, the increase of corrosion rate with internal pressure was shown to be relatively small. It was therefore suggested that the crack induced at the surface did not propagate to oxide layer in the vicinity of oxide/metal interface which is known to be protective to oxygen diffusion and to control the corrosion behavior. |
|
|
| Key Words |
| Zr alloys, Fuel cladding, Internal pressure, Corrosion, Oxide |
|
|
 |
|
