Structure evolution in InBiGaSnCu melt  
Bilyk R. M., Mudry S. I.
Physics of Metals Department, Ivan Franko National University of Lviv. 
Kyrylo and Mefodiy St., 8, Lviv-79005, Ukraine
E-mail: roman.bilyk@lnu.edu.ua

The development of new materials with predetermined physical and chemical properties remains one of the most important tasks of physical material science. It is known that there is a connection between the structure of materials and their physical properties. For example, mechanical properties of materials are determined by their structural characteristics and chemical composition, such as phase composition, grain size, a distribution of the excess phase inclusions by their size etc. One of the most promising materials, characterized by a unique combination of mechanical properties are nanocrystalline high-entropy alloys (HEA) containing up to 5-6 metallic components. However, up to now there is no single view on structure multicomponent alloys and HEA. Among high-entropy metal alloys special attention is attracted by the multicomponent alloys of Cu- and Al- based systems with transition elements (Fe, Co, Ni etc.), in which formation of a mixture of solid solutions based on bcc and fcc structures.				In  this  work  we attempt  to obtain the some results of the  main  structure  characteristics  5-component  alloy  InBiGaSnCu.  The experimental intensity curves were obtained in high-temperature X-ray diffraction camera for investigation of the metal melts. CuK - radiation, monochromatised with a LiF single crystal, installed into the primary beam. Intensity curves were corrected on polarization and incoherent scattering.  After normalization procedure the structural factors   and pair correlation functions have been calculated.		It was found the SFs for liquid     melt   have asymmetric principal peak and reveal the shoulder on right hand side, which is observed also in SF for liquid Ga, Bi and Sn.  Also we saw that the heights of the peaks depend on temperature.  We interpreted   that in this way:  decrease of peak heights is supposed to be related with topological disordering of structure with heating, which, according to the model of hard spheres, allowed us to conclude that the density of atomic packing at heating decreases. It is clear that increasing the temperature and decreasing the density makes the better conditions for mixing of atoms and as result for entropy increase.