High temperature creep in copper single crystals oriented for easy glide. Part II. Creep kinetics (in Czech) COCHNAR, Z., ZEMCIKOVA, M., CADEK, J. vol. 36 (1998), no. 5, pp. 348 - 357
Abstract A high initial creep strain rate is characteristic for creep in copper single crystal oriented for easy glide. The creep strain rate decreases in time rather quickly, but the steady state is not attained even at very large creep strains, if ever. In the present work, approximate values of the apparent activation energy Qc and the apparent stress exponent n are obtained from the lowest creep strain rates measured at any given temperature and the applied stress. From the macroscopic deformation of the oblong cross section specimen, the relative contribution of submicroscopic slip in two slip systems is estimated; these slip systems are associated with the highest values of the shear stress. It is found that the contribution of the submicroscopic slip associated with the main slip system may not be the most significant one. Key words copper, creep, creep deformation, single crystals, slip bands Full text not available
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