Creep Properties of AZ31 Magnesium Alloy at Elevated Temperature

AZ31 마그네슘 합금의 고온 크리프 특성

  • Chung, Chin-Sung (Department of Automotive Engineering, Seoul National University of Technology) ;
  • Kim, Ho-Kyung (Department of Automotive Engineering, Seoul National University of Technology)
  • 정진성 (서울산업대학교 자동차공학과) ;
  • 김호경 (서울산업대학교 자동차공학과)
  • Published : 2009.12.31

Abstract

The creep deformation behavior of AZ31 magnesium alloy was examined in the temperature range from 573 to 673K (0.62 to 0.73 Tm) under various constant stresses covering low strain rate range from $4{\times}10^{-9}\;s^{-1}$ to $2{\times}10^{-2}\;s^{-1}$. At low stress level, the stress exponent for the steady-state creep rate was ~3 and the present results were in good agreement with the prediction of Takeuchi and Argon model. At high stress level, the stress exponent was ~5 and the present results were in good agreement with the prediction of Weertman model. The transition of deformation mechanism from solute drag creep to dislocation climb creep could be explained in terms of solute-atmospherebreakaway concept.

Keywords

References

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