M.I. Ojovanb,c aBuryat State University, Smolina st. 24a, Ulan-Ude, 670000, Russian Federation bLomonosov Moscow State University, Vorobevy Gory, Moscow, 119991, Russian Federation cImperial College London, Prince Consort Road, London, SW7 2AZ, United Kingdom
Relaxation theories of the glass transition and viscous flow of glass-forming melts are presented. The main attention is devoted to modern representations of the glass transition equation qτg = δTg determining the appearance of a glassy state during cooling. Here, q=d T/dt is the temperature change rate during melt cooling and τg is the relaxation time at the glass transition temperature Tg. Various methods for calculating the characteristic temperature band δ Tg during the liquid—glass transition are considered. The generalized equation for the dependence of Tg on the melt cooling rate is derived. Based on the model of delocalized atoms, the modified kinetic glass transition criterion is discussed. The generalized viscosity equation for glass-forming liquids is derived.
Keywords: glass transition, amorphous polymers, inorganic glasses, metal amorphous melts, glass transition equation, viscosity, glass transition criterion, relaxation theories PACS:61.43.Gt, 64.70.Q−, 81.05.kf (all) DOI:10.3367/UFNe.2018.04.038319 URL: https://ufn.ru/en/articles/2019/2/a/ Citation: Sanditov D S, Ojovan M I "Relaxation aspects of the liquid—glass transition" Phys. Usp.62 111–130 (2019)