Improvement of Fatigue Properties in Ultrafine Grained Pure Ti after ECAP(Equal Channel Angular Pressing)

ECAP가공에 의한 초미세립 순수 티타늄의 피로 특성 향상

  • 이영인 (서울산업대학교 대학원 자동차공학과) ;
  • 박진호 (서울산업대학교 대학원 자동차공학과) ;
  • 최덕호 (서울산업대학교 대학원 자동차공학과) ;
  • 최명일 (덴티움(주) 기술연구소) ;
  • 김호경 (서울산업대학교 자동차공학과)
  • Published : 2005.11.01


Fatigue life and notch sensitivity of the ultrafine grained pure Ti produced by ECAP was investigated. The ECAPed sample with the true strain of 460$\%$ showed near equiaxed grains with an average size of about 0.3 $\mu$m. After ECAP, the ultimate tensile strength was increased by 60$\%$, while the tensile ductility was decreased by 31$\%$. The ECAPed ultrafine grained pure Ti samples showed high notch sensitivity and significant improvement of high cycle fatigue limit by a factor of 1.67. The ECAPed samples also show high notch sensitivity (K$_{f}$/K$_{t}$ = 0.96). It can be concluded that ECAP is the effective process for achieving high fatigue strength in Ti by increasing its tensile strength through grain refinement


Pure Ti;Equal Channel Angular Pressing;Ultrafine Grained Microstructures;Fatigue;Notch Sensitivity;Fatigue Limit


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