Processes of Self-Organization and Evolution of the Microstructure of Metals and Intermetallic Compounds under a Strong External Action

Abstract

Electron-microscopic studies of the processes of self-organization and evolution of the microstructure of metals and intermetallic compounds under different strong external actions are carried out. Special attention is given to the study of processes controlling the formation of explosively welded joints. Welded joints such as copper–tantalum, copper–titanium, aluminum–tantalum, titanium–orthorhombic titanium aluminide, steel–steel, etc., are studied. It is shown that the main mechanisms of self-organization in metals, which lead to the formation of stable joints after a very strong and short-term explosive action, are the fragmentation of two types, i.e., the formation of cusps and splashes, the formation of quasi-wave and wave interfaces, and local melting. The self-organization processes are also studied under the action of another kind of strong external action—severe plastic deformation by high-pressure torsion (HPT). It is shown that the effect of the self-locking of dislocations in the intermetallic compounds disappears upon torsion.