Slip line Studies of the Deformation of Copper–12 at% Aluminium Crystals in Stage I

The deformation in tension during stage I, of Cu–12 at% Al crystals, has been studied by observing the development of slip lines with the use of a new replica technique. The deformation is macroscopically inhomogeneous and in the less deformed regions consists of clusters of lines which widen asymmetrically as deformation proceeds. It is suggested that cross‐slip does not play a significant part in the widening of the slip clusters. The variation with local strain of slip line growth and initiation has been investigated quantitatively.