STRUCTURAL-PHASE TRANSFORMATIONS IN LOW-STABILITY CONDENSED STATE SYSTEMS

The conditions of formation of low-stability condensed state systems, their behavior and structure are investigated. The objects under study are alloys and compounds undergoing structural-phase transitions of the second type or close to it. The low-stability (pre-transitional) state is treated here as the state of a system near its structural-phase transformations, in which its structure and properties exhibit anomalies. An attempt is made to interpret the system from the physical standpoint relying on a new insight into its state, in which the traditionally accepted phase-transition point is represented by a range of values of the parameter controlling the transition. The material state within this range of values is structurally weakly stable in terms of slight variations in the controlling parameter. It is shown that the thermodynamics of structural-phase transformations of the material in this transient state is significantly affected by the interaction of structure defects.