Abstract
To determine the amount and type of secondary slip, the full deformation matrix was calculated from current orientation and shape measurements at successive strain intervals for copper crystals of various orientations deformed in tension at room temperature. The data for diverse orientations within the standard triangle are remarkably similar and represent a combination of response to internal stress and applied stress. Internal stress due to primary edge dislocations is relieved by the same combination of secondary shears in all orientations, two particular Lomer–Cottrell reactions plus a shear on the cross-glide plane giving zero residual stress. Analogous sets of shears occur to relieve internal stresses arising from conjugate glide after overshoot ends, and coplanar glide in orientations close to [111]–[110]. This type of slip, not visible at the surface, is termed microscopic secondary slip. Deviations from this microscopic secondary glide are always in the direction of applied stress. Except for the special case of positive and negative cross-slip, secondary slip lines visible at the surface, termed slip-line slip, represent slip occurring in response to applied stress.
Acknowledgement
I (S. J. B.) am indebted to my son, Dr A.S.H.Basinski, for converting my pen-and-paper figures to electronic form and for encouraging me to write up this work.
Notes
‡ Author for correspondence. Retired. Email: [email protected].
† Deceased 12 August 1999.
† Deceased 12 August 1999.