Papers by Author: D.S. Gertsriken

Abstract: Distribution and mobility of own and impurity atoms in metals subjected to different loadings: quasi-static plastic strains; quasi-static deformations in combination with impulse; sluggish and fast elastic deformations, including alternating, impulse plastic strains are investigated by methods of an autoradiography, layer-by-layer radiometric analysis and secondary ionic mass spectrometry. The common regularities of migration of atoms at deformation of metals are found, and threshold values of a strain rate, corresponding to change of the diffusion mechanism and localization of penetrating atoms in metal, are determined. The conclusion about the bulk mechanism of substance transfer is made at pulse actions irrespective of temperature of processing.

Abstract: Since 1975 a so-called anomalous mass-transfer in metals and alloys under pulse loading is being investigated in the Institute of Metal Physics. This phenomenon remains to be a challenge to theoreticians. Besides, one more phenomenon (observed at the same systems) was discovered – formation of metastable alloys (solutions, and, sometimes, ordered phases), with solubility limits far exceeding the equilibrium values and depending on the deformation rate. Since formation of nonequilibrium phases is also typical for alloys under irradiation, it seemed natural for us to use some of concepts and models invented in the “materials under irradiation” community. We propose 3 types of models for description of metastable solid solution formation in diffusion couple under pulse loading: 1) flux balance for both components at the interface with account of non-equilibrium defects generated during pulse loading; 2) “ballistic jump” concept, which had been invented by George Martin et al. for materials under irradiation or ball-milling, combined with another Martin’s kinetic model (1994) of diffusion; 3) modification of such a concept for the case of non-equilibrium interstitial defects. Non-equilibrium phase diagrams obtained by all 3 models are built and compared with experimental data which reflect a qualitative correspondence to one another.