Theoretical models of threshold stress intensity factor and critical hydride length for delayed hydride cracking considering thermal stresses

Jingyu Zhang; Jiacheng Zhu; Shurong Ding; Liang Chen; Wenjie Li; Hua Pang

추천

검색

자료유형: 학술저널

저자정보: Jingyu Zhang Jiacheng Zhu Shurong Ding Liang Chen Wenjie Li Hua Pang

저널정보: 한국원자력학회 Nuclear Engineering and Technology Nuclear Engineering and Technology 제50권 제7호

발행연도: 2018.1

수록면: 1,138 - 1,147 (10page)

이용수

📌

연구주제

📖

연구배경

🔬

연구방법

🏆

연구결과

초록· 키워드

오류제보하기

Delayed hydride cracking (DHC) is an important failure mechanism for Zircaloy tubes in the demandingenvironment of nuclear reactors. The threshold stress intensity factor, KIH, and critical hydride length, lC ,are important parameters to evaluate DHC. Theoretical models of them are developed for Zircaloy tubesundergoing non-homogenous temperature loading, with new stress distributions ahead of the crack tipand thermal stresses involved. A new stress distribution in the plastic zone ahead of the crack tip isproposed according to the fracture mechanics theory of second-order estimate of plastic zone size. Thedeveloped models with fewer fitting parameters are validated with the experimental results for KIH andlC. The research results for radial cracking cases indicate that a better agreement for KIH can be achieved;the negative axial thermal stresses can lessen KIH and enlarge the critical hydride length, so its effectshould be considered in the safety evaluation and constraint design for fuel rods; the critical hydridelength lC changes slightly in a certain range of stress intensity factors, which interprets the phenomenonthat the DHC velocity varies slowly in the steady crack growth stage. Besides, the sensitivity analysis ofmodel parameters demonstrates that an increase in yield strength of zircaloy will result in a decrease inthe critical hydride length lC , and KIH will firstly decrease and then have a trend to increase with the yieldstrength of Zircaloy; higher fracture strength of hydrided zircaloy will lead to very high values ofthreshold stress intensity factor and critical hydride length at higher temperatures, which might be themain mechanism of crack arrest for some Zircaloy materials

참고문헌 (24)

참고문헌 신청

M.P. Puls / 2012 / The Effect of Hydrogen and Hydrides on the Integrity of Zirconium Alloy Components: Delayed Hydride Cracking / Springer

K.S. Chan / 2013 / An assessment of delayed hydride cracking in zirconium alloy cladding tubes under stress transients / Int. Mater. Rev 58:349~373

T. Kubo / 2012 / Measurements of delayed hydride cracking propagation rate in the radial direction of Zircaloy-2 cladding tubes / J. Nucl. Mater 427:18~29

S. Shimada / 2004 / A metallographic and fractographic study of outside-in cracking caused by power ramp tests / J. Nucl. Mater 327:97~113

A.A. Shmakov / 2007 / A combined SIF and temperature model of delayed hydride cracking in zirconium materials / Comput. Mater. Sci 39:237~241

함께 읽어보면 좋을 논문

논문 유사도에 따라 DBpia 가 추천하는 논문입니다. 함께 보면 좋을 연관 논문을 확인해보세요!