GENERALIZED GINZBURG-LANDAU THEORY OF ANTIPHASE AND INTERPHASE BOUNDARIES FOR THE B2-TYPE AND L1_0-TYPE ALLOY ORDER

摘要

The earlier-described generalized Ginzburg-Landau approach for alloys is used to develop the statistical theory of equilibrium antiphase and interphase boundaries (APBs and IPBs) in the "continuous" approximation valid for the most of situations of practical interest. Within this approach, the structure of an APB or IPB in an alloy ordered with a single order parameter is determined by a second-order differential equation for the local concentration versus the local order parameter. Based on this equation and using various statistical methods, we consider a number of general properties of equilibrium APBs and IPBs in the B2 and L1_0 ordered structures. We study the dependence of their structure and energy on the concentration, temperature and the type of effective interaction; manifestations of "wetting", "critical" and "tricritical" phenomena in properties of these interfaces; orientational dependence of various characteristics of APBs and IPBs for the L1_0-type order; and other problems.