Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Change in Fracture Toughness within Heat-Affected Zone of SA-Welded 9% Ni Steel

LNG 저장탱크 내조용 9% Ni강의 SAW 용접열영향부내 파괴인성 변화 평가

  • Jang, Jae-Il ;
  • Lee, Jeong-Seok (School of Materials Science and Engineering, Seoul National School) ;
  • Lee, Baek-U (School of Materials Science and Engineering, Seoul National School) ;
  • Ju, Jang-Bok (School of Materials Science and Engineering, Seoul National School) ;
  • Gwon, Dong-Il (School of Materials Science and Engineering, Seoul National School) ;
  • Kim, U-Sik (Research and Development Center, Korea Gas Corporation)
  • 장재일 ((주)프론틱스 연구개발부) ;
  • 이정석 (서울대학교 재료공학부) ;
  • 이백우 (서울대학교 재료공학부) ;
  • 주장복 (서울대학교 재료공학부) ;
  • 권동일 (서울대학교 재료공학부) ;
  • 김우식 (한국가스공사 연구개발원)
  • Published : 2002.03.01
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Abstract

As one step for the safety performance of LNG storage tank, the change in fracture toughness within the X-grooved weld heat-affected zone (HAZ) of newly developed 9% Ni steel, which was submerged arc (SA)-welded, was investigated. Both crack initiation fracture toughness and crack arrest fracture toughness were evaluated by the crack tip opening displacement (CTOD) tests and compact crack arrest (CCA) tests. As the evaluated region approached the fusion line, each test result shorted different tendency, that is, crack initiation toughness decreased while crack arrest toughness increased. The results were discussed through the observation of the microstructural change.

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References

  1. 이종봉, 한재광, 1995, '최근9% Ni강의 용접 특성,' 대한용접학회지, 제13권, 제3호, pp. 34-45
  2. Kim, J. I., Kim, H. J., and Morris, Jr., J. W., 1983, 'The Role of the Constituent Phases in Determining the Low Temperature Toughness of 5.5 Ni Cryogenic Steel,' Metall. Trans., Vol. 14A, pp.2213-2219
  3. Jang, J.-i., Yang, Y.-c., Kim, W.-s., and Kwon, D., 1997, 'Evaluation of Cryogenic Fracture Toughness in SMA-Welded 9% Ni Steel thorouth Modified CTOD Test,' Met. & Mater. Int., Vol. 3, pp. 230-238 https://doi.org/10.1007/BF03025929
  4. Fracture Mechanics Toughness Tests, 1997, BS 7448 Part 2
  5. NSC Technical Report, 1993, 'Nippon Steel's Supply Records of 9% Ni Steel Plates for LNG Storage Tanks,' Nippon Steel Corporation
  6. Standard Test Method for Determining Plane-Strain Crack-Arrest Fracture Toughness, $K_{la}$, of Ferritic Steels, 1996, ASTM Standard E1221
  7. Nakao, Y., Oshige, H., and Noi, S., 1985, 'Distribution of Microstructures in HAZ of Multi-Pass Welded High Strength Steel,' Q. J. Jpn. Weld. Soc. Vol. 3, pp. 766 -773 https://doi.org/10.2207/qjjws.3.766
  8. Suzuki, M., Bessyo, K., Toyoda, M., and Minami, F., 1995, 'Property Distribution Map to understand HAZ CTOD Toughness.' Q. J. Jpn. Weld., Vol. 13, pp. 302-308 https://doi.org/10.2207/qjjws.13.302
  9. 장재일, 주장복, 김우식, 권동일, 2000, '초저온용 강 용접열영향부의 저온 파괴특성에 관한 금속조직학적 분석(I),' 대한금속재료학회지, 제 38권, 제8호, pp. 1001-1010
  10. Kim, J. I., and Morris, Jr., J. W., 1980, 'On the Scavenging Effect of Precipitated Austenite in a Low Carbon Fe-5.5Ni Alloy,' Metall. Trans., Vol. 11A, pp. 1401-1428 https://doi.org/10.1007/BF02653495
  11. Kim, J. I., Syn, C. K., and Morris, Jr., J. W., 1983, 'Microstructural Sources of Toughness in QLT-Treated 5.5 Ni Cryogenic Steel,' Metall. Trans., Vol. 14A, pp. 93 -103 https://doi.org/10.1007/BF02643742
  12. Tamura, H., Onzawa, G., and Uematsu, S., 1980, 'Retained Austenite and Notch Toughness in Synthetic HAZ of 9% Ni Steel,' J. Jpn. Weld. Soc., Vol. 49, pp. 854-860 https://doi.org/10.2207/qjjws1943.49.854
  13. Malik, L., Pussegoda, L.N., Graville, B.A., and Tyson, W.R., 1996, 'Crack Arrest Toughness of a Heat-Affected Zone Containing Local Brittle Zones,' J. OMAE, Vol. 118, pp. 292-300
  14. 장재일, 이정석, 정아람, 김우식, 권동일 ,2000, '9% Ni강 다층 용접열영향부의 취성파괴 저항성능에 미치는 LBZ 존재의 실질적 영향,' 대한금속재료학회지, 제38권, 제11호, pp. 1464-1471