Fracture Resistance Characteristics of SA516-Gr.70 Steel Plate for RCS Piping Elbow and Support Skirt

원자로 냉각재배관 엘보우 및 서포트 스컷트용

  • Son, Jong-Dong (Department of Mechanical Engineering, Tong Myong University) ;
  • Lim, Man-Bae (Department of Mechanical Engineering, Tong Myong University)
  • 손종동 (동명대학교 기계공학과) ;
  • 임만배 (동명대학교 기계공학과)
  • Published : 2006.08.31

Abstract

The evaluation of elastic-plastic fracture characteristic was investigated in ferrite steel SA 516- Gr70 used for reactor coolant piping elbow and support skirt of pressure vessels. This paper describes the effect of temperature on J-R curve characteristic of this material. The elastic-plastic fracture mechanics parameter J is obtained with unloading compliance method. The test method were analyzed according to ASTM E 813-89 and E 1152-89. Unloading compliance $J_{IC}$ tests were performed on 1 CT specimens at varied temperatures from $25^{\circ}C$ to about $400^{\circ}C$ using a high temperature extensometer. At all temperature, valid $J_{IC}$ measurements could be made and $J_{IC}$ decreased with increasing temperature. SEM fractography schematically illustrates microvoid initiation, growth and coalescence at the tip of a preexisting crack.

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