On some structuring features of metallic fluids

Physical models of metallic fluids structure have been analyzed. The state of a fluid can be described in physical terms if the proportion ratio is known: the number, composition and size of clusters, the number of atoms in clusters, the lifetime of clusters, the mean free path of electrons, etc. The possibilities of a quantitative description of the structural parameters which follow from the analysis of well-known publications and our proposals for their use have been considered. The greatest attention is paid to works in which the model representations proposed for discussion are based on the results of experimental studies. To develop a quantitative theory of a physical model, experimental methods are needed to determine the relative proportions of the structural components of the melts: the disordered zone and the cluster zone. It can be assumed that exactly these characteristics determine many structural-sensitive properties of melts and the processes associated with a change in their structure. It is shown that the most substantiated conclusions about structural transformations and changes in the nature of chemical bonds in liquid metals are those based on the results of complex studies of properties on the same object, as well as from the results of X-ray diffraction, neutron diffraction and other direct methods. For quasi-equilibrium metastable states of liquid that exist for a long time, a quasi-chemical version of the model of the microinhomogeneous structure of metallic melts has been proposed. Three fundamental ideas are taken into account: the uniformity of the two types of motion of fluid particles, the essential role of the forces of interatomic attraction in the formation of a condensed state and the features of the force fields of specific melt atoms. At the same time, special attention has been paid to the energy disparity in the interatomic interaction of atoms of different elements that is the cause for the emergence of clusters of different composition and structure which have different stability in time.