Mechanochemistry of solids:: Past, present, and prospects

A historical retrospective is presented beginning from the early observations by alchemists to the establishment of mechanochemistry as a branch of science. The changes in structure and chemical properties of solids under three-axes loading and by combined action of pressure and shift are demonstrated. The peculiarities of the phenomena taking place upon stressing of particle assemblies in various types of energy-intensive grinding mills are discussed. Based on the contemporary concepts, the mechanism of stress field formation and relaxation is analyzed. Among decisive factors influencing the mechanochemical synthesis, the formation and renewal of contact area between reacting compounds, the explosive evolution of heat, and the feedback phenomenon are emphasized. The perspective directions of practical application in the area known as mechanical alloying, as well as in preparation of functional ceramics and catalysts, and in pharmacy are discussed. The main directions for improving research, construction of milling devices, training of specialists, and exchange of knowledge are proposed.