Dislocation glide in non-compact crystal planes (in Czech) KVAPILOVA, M., ORLOVA, A. vol. 38 (2000), no. 3, pp. 206 - 222
Abstract Under appropriate conditions, dislocation glide can appear not only in compact crystal planes which are optimum for its realization, but also in other types of non-compact (NC) planes. The interest in a more systematical knowledge of this mechanism was increased in connection with its importance in modern metallic and inter-metallic materials, but the phenomenon was also widely investigated in pure metals. This paper tries to give an overview of a published knowledge on the non-compact dislocation glide mostly in metallic materials. It starts from model ideas and illustrates their realization by characteristic performances of the non-compact glide inexperiments. As mechanisms of the NC glide, the Peierls mechanism and the locking-unlocking combination can be accepted. In fcc metals, the NC glide can appear in several types of crystal planes, the intensity of its participation in straining, beside the glide in the compact planes, depends on the stacking fault energy and is a function of temperature. As thermally activated process, NC glide is characterized by an activation energy which is higher than the activation energy of lattice diffusion. In hcp metals, a pure NC glide can be realized. Deformation stresses of non-basal systems depend on the dislocation core structure and the stacking fault energy. In intermetallics, the NC glide assists in the motion of superdislocations and dislocations by acting in a cross slip between a compact and a NC plane. A similar participation of the NC glide is observed also in superalloys. The deformation stress anomaly at higher temperatures might be connected with a realization of the NC glide. Key words dislocation, glide motion, non-compact glide planes, experimental evidence Full text not available
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