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The purpose of the study was experimental verification of the proposed concept of phase formation in electrocrystallised metals/alloys via the stage of supercooled liquid state. In accordance with the purpose, the task was to reveal the features of formation of the crystallographic texture in metals/alloys during their electrocrystallisation under the action of small force. The effect of the emergence of a new crystallographic texture with lower surface energy in metals/alloys during electrocrystallisation under the action of small external force exerted in the direction opposite to the initial axis of the texture was experimentally established. The obtained result is one more proof of the validity of the concept of phase formation in electrocrystallised metals/alloys via the stage of supercooled liquid state. [ABSTRACT FROM AUTHOR]

A review of the author's works proving the existence of the phenomenon of the electrochemical phase formation in metals and alloys via a supercooled liquid state stage is presented. This review presents all the stages of establishing the above phenomenon in chronological order, as well as examples of its scientific and practical application. The theoretical prediction of the phenomenon, its experimental observation, theoretical substantiation, and some experimental proofs confirming its existence are considered in detail. The mechanism and thermodynamic model of crystallographic texture formation in electrochemical coatings, developed on the basis of the concepts of the phase formation in electrodepositing metals/alloys, taking into account the intermediate stage of the supercooled liquid state, are discussed. Some areas of the practical application of the phenomenon in basic industries (metallurgy, power engineering, and space engineering), concerning the development of the technologies for obtaining electrochemical films/coatings/foils with enhanced properties, are presented. [ABSTRACT FROM AUTHOR]

A review of experimental author’s works proving the existence of the phenomenon of the electrochemical phase formation in metals and alloys via a supercooled liquid state stage is presented. The research findings focused on the electrochemical formation of metastable structures and intermediate phases, as well as on the structural features accompanying them. Electrochemical amorphous phase formation in metals and alloys, electrochemical quasicrystalline phase formation in metals, and electrochemical polymorphic phase formation in metals are discussed. Electrochemical hydrogen-related structure formation in metals, electrochemical high-defect crystalline phase formation in metals, and electrochemical texture-inhomogeneous structure formation in metals are considered. Electrochemical formation of intermediate phases in metals and alloys, electrochemical formation of eutectics in metallic alloys, and electrochemical formation of chemical compounds at the metallic cathode/electrodepositing metal interface are analyzed. Electrochemical reduction of ions in metals and alloys at a liquid cathode versus a solid chemically identical one, electrochemical phase formation of metals at chemically identical solid or liquid cathode, and electrochemical phase formation of alloys at chemically identical solid or liquid cathode are discussed. [ABSTRACT FROM AUTHOR]

The aim of this work was the further experimental verification of the existence of the phenomenon of electrochemical phase formation in metals and alloys via a supercooled liquid state stage. Assuming that the phase formation in electrodeposition of metals involves occurrence of some deeply supercooled metallic liquid and its subsequent ultrarapid solidification, it was suggested that quasicrystals may be present in deposit layers next to the cathode. A further suggestion was that such electrochemical phase formation via metal's supercooled liquid state must present a possibility to produce electrodeposits in the form of phases with completely quasicrystalline structure. It was found that the phenomenon under study here is proved by the following experimental facts: (1) occurrence of quasicrystals in electrodeposit layers next to the cathode, a behaviour similar to that in interface-near metal layers at crucible walls in ultrarapid solidification of a deeply supercooled melt; and (2) electrochemical phase formation in metals resulting in phases with quasicrystalline structure when formation of a periodically ordered crystal structure is hindered in the course of deposition. [ABSTRACT FROM AUTHOR]

The phenomenon of electrochemical phase formation in metals via a supercooled liquid state stage is discussed. Experiments are carried out aiming to verify its existence. It is found that the amorphous structure typical of a solidified metallic liquid did form in the course of metals electrodeposition when crystallization is hindered. The experimental findings verify the existence of the phenomenon of electrochemical phase formation via a stage of a supercooled liquid state. [ABSTRACT FROM AUTHOR]