The detection of secondary slip during the deformation of copper and α-brass single crystals

Deviations from single glide during the deformation of Cu single crystals have been detected by following the orientation of the tensile axis using x-ray techniques. The deviations for room temperature deformation of some crystals can be explained if it is assumed that 5–10% of the elongation is produced by slip on the secondary systems and the remainder on the primary system. The deviations from single glide are much smaller in α-brass crystals which also show more overshoot, so that secondary slip is inhibited. It is suggested that secondary slip is produced near the heads of piled-up groups of primary dislocations at the ends of newly formed slip lines where the resolved shear stress on the secondary systems is high. Secondary slip is thus very localized, producing little strain, but it can give rise to a high forest density.