Transactions of the Korean Society of Pressure Vessels and Piping (한국압력기기공학회 논문집)

Korean Society of Pressure Vessels and Piping (한국압력기기공학회)
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Microstructure characterization technique of spacer garter spring coil X-750 material

스페이서 가터 스프링 코일 X-750 소재 정밀 조직 분석 방법

  • 진형하 (한국원자력연구원 (재료안전기술연구부)) ;
  • 류이슬 (한국원자력연구원 (재료안전기술연구부)) ;
  • 이경근 (한국원자력연구원 (재료안전기술연구부))
  • Received : 2021.11.11
  • Accepted : 2021.12.16
  • Published : 2021.12.31
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Abstract

In the periodic surveillance material test for the spacer component of fuel channel assembly in CANDU, a microstructural characterization analysis is required in addition to the mechanical property evaluation test. In this study, detailed microstructure analysis and simple mechanical property evaluation of archive spacer parts were conducted to indirectly support the surveillance test and assist in the study of spacer material degradation. We investigated the microstructural characteristics of the spacer garter spring coil through comparative analysis with the plate material. The main microstructure characteristics of the garter spring coil X-750 are represented by the fine grain size distribution, the ordering phase distribution developed inside the matrix, the high dislocation density inside the grains, and the arrangement of coarse carbides. In addition, the yield strength of the garter spring coil X-750 was indirectly evaluated to be approximately 1 GPa. We also established an analytical method to elucidate the microstructural evolution of the radioactive spacer garter spring coil X-750 based on Canadian research experiences. Finally, we confirmed the measurement technique for helium bubble formation through TEM examination on the helium implanted X-750 material.

Keywords

Acknowledgement

This work was supported by the Ministry of Science and ICT and the National Research Foundation of Korea (NRF) grant funded by the Korea government (2017M2A8A4015157)

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