Journal of the Korean Society of Safety (한국안전학회지)

The Korean Society of Safety (한국안전학회)
권호 표지

Fatigue Crack Propagation Behavior of Fine Grained Al-5083 Alloy Produced by Severe Plastic Deformation

강소성법을 이용한 미세립 Al-5083 합금의 피로균열전파 거동

  • Kim, Ho-Kyung (Department of Automotive Engineering, Seoul National University of Technology) ;
  • Yang, Kyoung-Tak (Graduate School, Seoul National University of Technology) ;
  • Kim, Hyun-Jun (Graduate School, Seoul National University of Technology)
  • 김호경 (서울산업대학교 자동차공학과) ;
  • 양경탁 (서울산업대학교 대학원) ;
  • 김현준 (서울산업대학교 대학원)
  • Published : 2007.04.30
Download PDF
⟨ Previous Next ⟩

Abstract

Fine grained Al-5083 alloy produced by equal channel angular pressing (ECAP) at $120^{\circ}C$ was tested for investigating mechanical properties and crack growth propagation behavior. Also, FEM stress and strain analysis for the samples during ECAP were investigated, using a plastic deformation analysis software DEFORM 2-D. Coarse grained as-received samples exhibited UTS of 255.6MPa with a elongation to failure of 34.4%. By contrast, the ECAPed fine grained samples exhibited UTS of 362.0MPa with a elongation to failure of 12.9%. Fatigue crack growth resistance and threshold of fine grained samples were lower than that of as-received coarse grained samples. The higher fatigue crack growth rate in the fine grained ECAPed samples may partially arise from small roughness closure effect due to smoother fracture surfaces.

Keywords

References

  1. V.M.. Segal, 'Materials processing by simple shear', Mater. Sci. Eng. A, Vol. 197, pp. 157-164, 1995 https://doi.org/10.1016/0921-5093(95)09705-8
  2. M. Furukawa, Z. Horita, M. Nemoto, R.Z. Valiev, T.G. Langdon, 'Microhardness measurements and the Hall-Petch relationship in an Al-Mg alloy with submicrometer grain size' Acta Metall. et Mater., Vol. 44, pp. 4619-4629, 1996 https://doi.org/10.1016/1359-6454(96)00105-X
  3. S.L. Semiatin, D.P. DeLo, 'Equal channel angular extrusion of difficult-to-work alloys' Mater. & Designs, Vol. 21, pp. 311-322, 2000 https://doi.org/10.1016/S0261-3069(99)00085-0
  4. M. Mabuchi, H. Iwasaki, K. Yanase, K. Higash, 'Low temperature superplasticity in an AZ91 magnesium alloy produced by ECAE' Scripta Mater., Vol. 36, No. 6, pp. 681-686, 1997 https://doi.org/10.1016/S1359-6462(96)00444-7
  5. D.H. Shin, K.H. Oh, W.J. Kim, S.W. Lee, W.Y. Choo, 'ECAP강가공에 의한 0.15%C강의 결정립 미세화', 대한금속학회지, Vol. 37, pp. 1048- 1054, 1999
  6. M.K. Rabinovich, M.V. Markushev, 'Influence of fine grained structure and superplastic deformation on the strength of aluminum alloys', J. Mater. Sci. Vol. 30, pp. 4692-4702, 1995 https://doi.org/10.1007/BF01153080
  7. S.R. Agnew, J.R. Weertman, 'Cyclic softening of ultrafine grain copper' Mater. Sci. Eng. A, Vol. 244, pp. 145-153, 1998 https://doi.org/10.1016/S0921-5093(97)00689-8
  8. V. Patlan, A. Vinogradov, K. Higashi, K. Kitagawa, 'Overview of fatigue properties of fine grain 5056 Al-Mg alloy processed by equal-channel angular pressing' Mater. Sci. Eng. A Vol. 300, pp. 171- 182, 2001 https://doi.org/10.1016/S0921-5093(00)01682-8
  9. S.R. Agnew, A. Vinogradov, S. Hashimoto, J.R.. Weertman, 'Overview of fatigue performance of Cu processed by severe plastic deformation', J. Electronic. Mater. Vol. 28, No. 9, pp. 1038-1044, 1999 https://doi.org/10.1007/s11664-999-0181-0
  10. Y. Iwahashi, M. Furukawa, Z. Horita, M. Nemoto, T.G. Langdon, 'Microstructural characteristics of ultrafine-grained aluminum produced using equalchannel angular pressing' Met. & Mater. Trans. A, Vol. 29A, pp. 2245-2252, 1998
  11. DEFORM2D, Scientific Forming Technologies Corporation
  12. ASTM E647-93: Standard test method for measurement of fatigue crack growth rates
  13. A. Vinogradov, S. Nagasaki, V. Patlan, K. Kitagawa, M. Kawazoe, 'Fatigue properties of 5056 Al-Mg alloy produced by equal-channel angular pressing', Nano Struct. Mater. Vol. 11 No. 7, pp. 925-934, 1999 https://doi.org/10.1016/S0965-9773(99)00392-X
  14. S.K. Jha, K.S. Ravichandran, 'Effect of mean stress (stress ratio) and aging on fatigue-crack growth in a metastable beta titanium alloy' Met. & Mater. Trans. A, Vol.3 1A, pp. 703-714, 2000