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http://dx.doi.org/10.3795/KSME-A.2006.30.12.1526

Degradation of Thermal Creep by Hydrides of Zr-2/5Nb Pressure Tube  

Oh, Dong-Joon (안동대학교 기계교육과)
Ma, Young-Wha (중앙대학교 기계공학부)
Yoon, Kee-Bong (중앙대학교 기계공학부)
Kim, Young-Suk (한국원자력연구소)
Publication Information
Transactions of the Korean Society of Mechanical Engineers A / v.30, no.12, 2006 , pp. 1526-1533 More about this Journal
Abstract
The aim of this research was to confirm the existence of the thermal creep degradation by hydrides of Zr-2.5Nb pressure tube materials. Small punch creep tests were performed to obtain the relationship between a creep displacement and a loading period at $300^{\circ}C$. A creep stress and a creep strain rate were also converted from the previous results. The creep material constants and the creep stress exponents at the different hydride contents were compared. Finally the hydrides of the axial and circumferential section were observed using OM, SEM and TEM. The following conclusions were made: 1) The degradation of the thermal creep by hydrides was existed and it strongly depended on the hydride contents. 2) As the hydride contents were increased, the creep stress exponents (m) were also increased. 3) Even though the hydride was not precipitated in 50 ppm materials at $300^{\circ}C$, the degradation of thermal creep was found. Therefore, it was believed that this phenomenon strongly related to the hydride precipitation at room temperature.
Keywords
Hydride; Pressure Tube; Small Punch Creep Test; Degradation; Thermal Creep; Hydrogen Embrittlement;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
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