• 한국세라믹학회지
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• 제47권2호
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• pp.106-112
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• 2010

This paper presents some experimental results on incubation time for massive hydriding of Zr alloys with oxide thickness. Oxide effects experiments on massive hydriding reaction of commercial Zr alloy claddings and pre-oxidized Zr alloys with hydrogen gas were carried out in the temperature range from 300 to $400^{\circ}C$ with thermo-gravimetric apparatus. Experimental results for oxide effects on massive hydriding kinetics show that incubation time is not proportional to oxide thickness and that the massive hydriding kinetics of pre-filmed Zr alloys follows linear kinetic law and the hydriding rate are similar to that of oxide-free Zr alloys once massive hydriding is initiated. There was a difference in micro-structures between oxide during incubation time and oxide after incubation time. Physical defects such as micro-cracks and pores were observed in only oxide after incubation time. Therefore, the massive hydriding of Zr alloys seems to be ascribed to short circuit path, mechacical or physical defects, such as micro-cracks and pores in the oxide rather than hydrogen diffusion through the oxide resulting from the increase of oxygen vacancies in the hypostoichiometric oxide.

• 한국재료학회지
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• 제18권11호
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• pp.597-603
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• 2008

Oxide effects experiments on massive hydriding reactions of Zr alloy with hydrogen gas were carried out at $400^{\circ}C$ under 1 atm in a $H_2$ environment with a thermo-gravimetric apparatus (TGA). Experimental results for oxide effects on massive hydriding kinetics show that incubation time is not proportional to oxide thickness. The results also show that the massive hydriding kinetics of pre-filmed Zr alloys follows linear kinetic law and that the hydriding rates are similar to that of oxide-free Zr alloys once massive hydriding is initiated. Unlikely microstructure of the oxide during incubation time, physical defects such as micro-cracks and pores were observed in the oxide after incubation time. Therefore, it seems that the massive hydriding of Zr alloys can be ascribed to short circuit paths and mechanical or physical defects, such as micro-cracks and pores in the oxide, rather than to hydrogen diffusion through the oxide resulting from the increase of oxygen vacancies in the hypo-stoichiometric oxide.

• Nuclear Engineering and Technology
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• 제25권4호
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• pp.570-587
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• 1993

최근 전 세계적으로 내부2차수소 침투에 의한 것으로 보이는 핵연료의 심각한 파손이 잇달아 보고되었다. 본 논문에서는 결함 핵연료에서의 내부 수소 침투 현상이 개괄적으로 고찰된다. 먼저 핵연료의 피복관으로 사용되는 질코늄 합금의 개발사와 그 질코늄 합금이 사용되는 원자로 내의 운전조건이 소개되고 산화 질코늄 막에서의 수소의 투과성, 질코늄과 질코늄 합금에서의 수소의 최종 용해도와 침전도등 질코늄의 수소 침투에 관련된 기본 사항과 수소 침투가 기계적 강도에 미치는 악 영향등이 고찰된다. 결함 핵연료봉 내부에서 발생되는 수소의 대량 내부 침투의 메카니즘이 관찰된 제 현상을 중심으로 정성적으로 설명되고 이러한 수소의 대량 침투에 의한 핵연료치 파손심화를 줄이기 위한 노력의 일환으로 제시된 정량적 모델이 간단히 언급되고 이러한 정량적인 모델의 심도있는 개발을 위해 필요한 자료와 추후의 연구 내용이 설명된다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 춘계학술발표회요약집
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• pp.239-239
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• 1999