A study of equilibrium states of a thermodynamic system whose evolution is governed not only by the temperature, but also by the ordering field is carried out. It is found that an adiabatically insulated system may have a new type of nonuniform state of equilibrium which is inhomogeneous in temperature. The comparison is made of the stability conditions in isothermal and adiabatic systems. The steady motion of an interface boundary during a firstorder phase transition is investigated. It is shown, that depending upon the values of the diffusion coefficients, different regimes can exist. For small thermal diffusivity, the temperature of the final phase after the exothermal transition can be above the equilibrium point. The kinetic problem is reformulated to a dynamical system, and a numerical procedure to solve the latter is presented. Numerical results are discussed in comparison with analytic ones.

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An experiment on the early stages of intermetallic compound layer growth during soldering and its theoretical analysis were conducted with the intent to study the controlling factors of the process. An experimental technique based on fast dipping and pulling of a copper coupon in liquid solder followed by optical microscopy allowed the authors to study the temporal behavior of the sample on a single micrograph. The technique should be of value for different areas of metallurgy because many experiments on crystallization may be described as the growth of a layer of intermediate phase.Comparison of the experimental results with the theoretical calculations allowed one to identify the kinetics of dissolution as the rate-controlling mechanism on the early stages and measure the kinetic coefficient of dissolution. A popular model of intermetallic compound layer structure coarsening is discussed.

Theoretical work in the field of interfacial segregation is mainly focused on the Gibbsian approach that uses the dividing surface construct. In this article a continuum approach to the problem of interfacial segregation in multicomponent hydrostatically compressed alloys is developed and the segregation at homophase and heterophase interfaces is considered on common grounds. The Gibbs adsorption theorem is derived in the framework of an isoperimetric problem, and a comparison is made with the dividing surface construct approach. The interfacial segregation is calculated for the case of a linear thermodynamic system where it is found to vanish at a heterophase interface and have a critical dependence on the temperature and composition at a homophase interface. The physical driving force for the interfacial segregation is discussed.

Dynamical Ginzburg-Landau theory is applied to the study of thermal effects of motion of interfaces that appear after different phase transitions. These effects stem from the existence of the surface thermodynamic properties and temperature gradients in the interfacial transition region. Thermal effects may be explained by the introduction of a new thermodynamic force exerted on the interface, called here Gibbs-Duhem force, and the internal energy density flux through the interface. The evolution equations for the interfacial motion are derived. For the experimental verification of the thermal effects during continuous ordering the expression is derived for the amplitude of temperature waves.