Values of a plasticity characteristic ?H for different materials were determined by the indentation method at cryogenic temperatures. Using the linear dependence ?H(T) at low temperatures, the value of δH at 0 K, designated by δH(0), was obtained by the extrapolation method. Values of δH(0) for different materials, namely FCC, HCP and BCC metals, intermetallics, metallic glasses, quasicrystals, ceramics and covalent crystals, are discussed. An analytic expression for a dependence of δH(0) on the parameters of thermoactivated movement of dislocations, melting point and Young’s modulus E is obtained. It is shown that any type of hardening of a crystal and an increase in the Peierls–Nabarro stress σS(0) reduce δH(0). Only a rise in E leads to the simultaneous increase in σS(0) and δH(0). δH(0) can be considered as a dislocation plasticity in the absence of thermal vibrations of atoms and should be considered together with strength parameters as an important fundamental characteristic of dislocation properties.
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