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Acta Physica Academiae Scientiarum Hungaricae

, Volume 50, Issue 4, pp 403–408 | Cite as

Effect of pre-strain on the steady state creep of Al-5 wt% Mg

  • N. K. Gobran
  • F. M. Mansy
Condensed Matter
  • 11 Downloads

Abstract

Steady state creep in Al-5 wt% Mg was studied at different stresses from 30 to 90 MPa and at temperatures ranging from 563 K to 613 K. For the pre-annealed samples the applied stress sensitivity parameter “n” was found to be stress independent and amounted to 3.9. While, for samples pre-strained by 20% “n” was equal to 3 at low stresses and 6 at high stresses. The activation energy for steady creep was found to be 143 kJ/mole for the annealed specimens. The controlling mechanism was considered to be the diffusion of Mg in Al matrix. For pre-strained samples, however, the activation energy was stress-dependent and varied from 104 kJ/mole to 84 kJ/mole. The predominant process responsible for creep in the cold worked matrix seemed to be cross-slip of dislocations.

Keywords

Activation Energy Applied Stress Creep Rate Stress Exponent Steady State Creep 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© with the authors 1981

Authors and Affiliations

  • N. K. Gobran
    • 1
  • F. M. Mansy
    • 1
  1. 1.Physics Department, Faculty of ScienceUniversity of CairoGizaEgypt

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