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Information × Registration Number 0220U103860, 0120U103623 , R & D reports Title Non-Schmid behavior of dislocations in magnesium alloys popup.stage_title Head Pal-Val Pavel P., Доктор фізико-математичних наук Registration Date 25-11-2020 Organization B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine popup.description2  The calculations were performed using the potential of the embedded atom method and using LAMMPS for modeling and OVITO for visualization. Sun and Kim potentials provide the best agreement with DFT and experimental data on dislocation properties. It is shown that the non-Schmidian behavior of screw dislocation can be observed in atomistic Mg models. The effect is appears as dependence of the critical resolved shear stresses on the non- glide component of the applied stress. Deviations from Schmid's law for basal and prismatic slip systems in Mg are established. It is shown that the application of pressure can change the critical allowable stress for basal and prismatic slip. The effect depends on the structure of the dislocation cores, as well as on the interatomic potentials used. This may be due to the dependence of the volume modulus of elasticity, excess volume and transient dilatation of the dislocation cores. According to the study of low-temperature acoustic properties of samples of fine-grained magnesium, the temperature limit of the dominant action of the mechanism of thermoactivated overcoming by dislocations of local barriers in magnesium has been established. The project has produced results of significant scientific and practical results that can help to better understand the mechanisms of plastic deformation, as well as improve the prediction of the formation of the structure obtained during severe plastic deformation and be used to establish the relative effect of thermal activation on the mobility of dislocations in magnesium in a wide range of temperatures. Product Description popup.authors popup.nrat_date 2020-11-25 Close