Stress Versus Temperature Dependence of Activation Energies for Creep Academic Article uri icon

abstract

  • The activation energy for creep at low stresses and elevated temperatures is associated with lattice diffusion, where the rate controlling mechanism for deformation is dislocation climb. At higher stresses and intermediate temperatures, the rate controlling mechanism changes from dislocation climb to obstacle-controlled dislocation glide. Along with this change in deformation mechanism occurs a change in the activation energy. When the rate controlling mechanism for deformation is obstaclecontrolled dislocation glide, it is shown that a temperature-dependent Gibbs free energy does better than a stress-dependent Gibbs free energy in correlating steadystate creep data for both copper and LiF-22mol percent CaF2 hypereutectic salt. © 1992 by ASME.

author list (cited authors)

  • Freed, A. D., Raj, S. V., & Walker, K. P.

citation count

  • 12

publication date

  • January 1992