Measurement of microstructure and eutectic penetration rate on irradiated metallic fuel after high-temperature heating test

• Published in: Metals and materials international Vol. 23; no. 3; pp. 504 - 511
• Main Authors: Kim, June-Hyung, Cheon, Jin-Sik, Lee, Byoung-Oon, Kim, Jun-Hwan, Kim, Hee-Moon, Yoo, Boung-Ok, Jung, Yang-Hong, Ahn, Sang-Bok, Lee, Chan-Bock
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Institute of Metals and Materials 01.05.2017; Springer Nature B.V; 대한금속·재료학회
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Cladding; Dual phase steels; Electron probe microanalysis; Electron probes; Energy research; Engineering Thermodynamics; Eutectic temperature; Ferritic stainless steels; Fission products; Flow velocity; Heat and Mass Transfer; High temperature; Iron constituents; Irradiation; Machines; Magnetic Materials; Magnetism; Manufacturing; Martensitic stainless steels; Materials Science; Metal fuels; Metallic Materials; Microstructure; Optical microscopy; Oxidation; Penetration; Processes; Scanning electron microscopy; Solid Mechanics; Stainless steel; Uranium base alloys; Zirconium; 재료공학; metals; melting; microstructure; scanning electron microscopy (SEM); optical microscopy
• ISSN: 1598-9623; 2005-4149
• DOI: 10.1007/s12540-017-6515-1

Microstructural development of irradiated U-10Zr fuel slug with T92 cladding specimen was examined after thermal exposure of 750 °C for 1 h. Optical microscopy, scanning electron microcopy and electron microprobe analysis were employed to examine the microstructure, constituent migration, and eutectic penetration. Migration phenomena of U, Zr, Fe, and Cr indicative of Soret effect was observed, and Nd lanthanide fission product was found at the eutectic melting region. Eutectic penetration was quantified and correlated to a thermal activation model with a good agreement. Compared to the previously reported eutectic penetration rates for the unirradiated U-10Zr fuel slug with FMS (Ferritic Martensitic Steel, HT9) cladding specimens, the eutectic penetration rate determined from this study for the irradiated fuel specimen was higher. This phenomenon can be caused by the effect of lanthanide fission product migration into fuel slug-cladding interface during irradiation, and lowering the eutectic threshold temperature for the irradiated fuel.