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


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.


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