Effects of impurity on low temperature anomalies of plasticity parameters of b-Sn

Abstract

Plastic deformation determined by (100)<010> screw dislocation slip of solid solution single crystals of b-Sn with various concentrations of Cd, In and Zn is studied in a temperature range 1.6√150 K. Low temperature anomalies of flow stress t₀ and activation volume g were revealed (kinks in the temperature dependencies of flow stress t₀(T) and peaks in the stress dependencies of activation volume g(t)). The parameters of the anomalies are found to be essentially dependent on impurity atom concentration and dislocation barrier force. The regularities of the effects observed are compared with the theory predictions describing the influence of impurity on dislocation motion through the Peierls barriers of complex shape. The results of experimental data analysis are in agreement with the assumption of camel hump shape of the lattice potential relief in the (100)<010> slip system.