Abstract
The width of symmetrical, threefold stacking‐fault nodes in a Cu‐13–43 at. % Al alloy has been measured as a function of node character by means of weak‐beam electron microscopy. The stacking‐fault energy (γ) has been determined independently of the measurement of the width of single, straight, dissociated dislocations on the same specimens. These results have been combined to estimate the dislocation core cut‐off parameter r 0 using anisotropic elasticity theories due to Scattergood and Bacon (1976), and also to ?. ?. ?. Kirchner and F. Prinz (1979, private communication).