Zircaloy-4 피복관의 KEC 파괴인성시험법 개발

다국어 초록 (Multilingual Abstract)

To define the causes of cladding degradation which can take place during an operation of nuclear power plants, it is required to develop the new fracture toughness test of fuel cladding. The fracture toughness of Zircaloy-4 cladding has been estimated using the recently developed KAERI embedded Charpy (KEC) specimen. Axially notched KEC specimens which were cut directly from fuel claddings, have been tested in a way similar to the standard toughness test method for a Single Edge Bending (SEB) specimen. The results of KEC fracture toughness test at room temperatures were compared with the test data of the previous studis and discussed. In conclusions, even though the KEC fracture toughness test for fuel claddings was easier and more reliable than those developed earlier, the results from the cladding fracture tests were not the material characteristics but the specific fracture parameters which was deeply related to the specification of claddings. In addition, the phenomenon of a thickness yielding was not observed from the fracture surface. It was closely related to the fact that the plane strain condition of the KEC specimen was changed to the plane stress condition during crack advancing. It was also supported by the fractographic evidence that the formation of ductile dimple at the crack initiation became the similar state such as a quasi-cleavage.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 재료 및 실험방법
• 3. 시험 결과 및 논의
• 4. 결론
• 후기
• 참고문헌