An Evaluation on the Fatigue Strength Characteristics for the Shot Peening Spring Steel at Low Temperature

숏피닝 가공재의 저온 피로 강도 평가

  • 박경동 (부경대학교 기계공학부) ;
  • 권오헌 (부경대학교 안전공학과)
  • Published : 2003.09.01

Abstract

In this study, CT specimens were prepared from spring steel(SPS5) processed shot peening. The fatigue crack growth tests were carried out in the environment of the room temperature md low temperature at $25^{\circ}C$, $-30^{\circ}C$, $-50^{\circ}C$, $-70^{\circ}C$ $-100^{\circ}C$ and $-150^{\circ}C$ in the range of stress ratio of 0.05 by means of opening mode displacement. The threshold stress intensity factor range ΔKth in the early stage of fatigue crack growth (Region I) and stress intensity factor range $\Delta$K in the stable of fatigue crack growth (Region II) were decreased in proportion to descend temperature. It was shown that the fatigue resistance characteristics and fracture strength at low temperature are considerable higher than those of mom temperature in the early stage and stable of fatigue crack growth region.

Keywords

References

  1. 박경동, 정찬기, "SA516강의 탄소성 파괴인성평가에 관한 연구", 한국해양공학회 논문집, 제34권 제1호, pp. 37-44, 2001
  2. 박경동, 정찬기, 'JISG4081SUP7-DIN50CrV4강의 피로강도에 미치는 숏피닝의 영향', 한국해양공학회 논문집, 제15권 제4호, pp. 66-72, 2001
  3. 정성균, 이승호, 쇼트피닝 加工槪論, 世和출판사, PP. 13-29, 1978
  4. ASTM : E647-93, Standard Test Method forMeasurement of Fatigue Crack Growth Rates, pp. 57-63, 131-135, 1993
  5. 배성인, 한민구, '파괴역학 실험법', 원창출판사, pp. 8-11, 1995
  6. P. C. Paris and F. Erdogan, Trans. of the ASME Ser. D, pp. 528-534, 1963
  7. Y. Kitsunai, 'Fatigue Crack growth Behavior in Mild Steel Weldments at Low Temperature', pp.280-290, 1991
  8. 박경동, 노태영, 김영대, 김형자, 손재윤, '압력용기용 A516강의 저온피로 크랙전파특성에 관한 연구', 한국해양공학회지, 제13권, 제3(1)호 pp. 108-115, 1999
  9. 이용복, 김호경, 정진성, 피로해석의 기초, pp. 99-125, 1999
  10. 박경동, 김정호, 정찬기, 하경준, '압력용기용 강의 저온 피로크랙 하한계 특성에 관한 연구(II)', 한국해양공학회 논문집, 제14권, 제3호, pp. 78-83, 2000