Participation of non-compact dislocation glide in creep of copper at high temperatures

A possible participation of dislocation glide in non-compact crystal planes of copper in the high temperature creep process is assessed by means of va lues of activation energy. The activation energy of creep was determined al ternatively from conventional data analysis, from the concept of effective and internal stresses applied to steady-state creep, and from constant-stru cture creep data. The results are discussed and compared with activation en thalpies of the {001} and {110} glide calculated from the kink-pair model. The calculated values are higher than the activation enthalpy of lattice di ffusion. However, the activation energy of creep, which is lower than the v alue for lattice self-diffusion indicates rather a participation of a proce ss with a lower activation energy than of the relatively difficult non-comp act glide. (C) 2001 Elsevier Science B.V. All rights reserved.