An Analysis of the Cottrell‐Stokes Law

The retarding force profiles available for copper and its solid‐solutions are shown to explain reported deviations from the Cottrell‐Stokes law. It is shown that the Cottrell‐Stokes law is not valid and only approximated when a large athermal force must be overcome by an applied stress attempting to translate a dislocation segment past a rate‐controlling obstacle to dislocation motion.