High temperature creep in copper single crystals oriented for easy glide Part I. Slip pattern

In the first part of the present paper, the slip pattern of copper single c rystals oriented for easy glide, subjected to creep at temperatures 873, 92 3, and 973 K and applied stresses ranging from 3 to 12 MPa is investigated. Creep testing times ranged from 1 to 6000 ks, the creep strains did not ex ceed 0.09. The contribution to the creep strain due to slip in slip bands, epsilon(SB), increases with applied stress a but does not depend on tempera ture significantly. With increasing applied stress the mean height of surfa ce steps associated with slip bands decreases but the density of these step s increases. The inhomogeneity of creep deformation in single crystals is d ue to the appearance of zones with restricted development of the slip bands . These zones are oriented perpendicularly to the slip vector of the domina nt slip system. Observed appearance of "small" slip bands of the secondary slip system is discussed. These slip bands are developed at the highest tes ting temperature and low applied stresses.