Title screen

The results of the correlations search between crystal-geometric parameters and structural-phase state features in alloys based on Rh-Me (Me = Fe, Ru, Os, Co, Ir, Ni, Pd, Pt, Cu, Ag, Au, Ga) are presented. Binary phase diagrams in the Rh-based systems with VIIIA groups elements of the Mendeleyev table are shown and the electronic structure and type of structure of alloy-forming elements in these systems are presented. Thermodynamic and dimensional factors were used for the analysis of binary diagrams state of systems based on Rh: entropy (nS), temperature (nT) and total volume (n0) factors. It is shown that it is most expedient to use the total volume factor n0, which is the sum of three elements: the effective ionization potentials of the fused elements, the volume and size factors. The threshold values of the total volume factor n0 for the formation of unbounded solid solutions in binary systems: nS ?1,10. A significant deviation of the experimental concentration dependences of the atomic volume in solid solutions and intermetallic compounds from the Xena law was established. The concentration dependences of the space occupancy coefficient for solid solutions and intermetallic compounds are obtained. The correlation between the state diagrams types and the deviation features of the atomic volume from the Xena law is analyzed. On the basis of the analysis of crystal-geometric and crystallochemical parameters of solid solutions and intermetallic compounds in systems of VIIIA group elements in Mendeleev's table it was revealed a characteristic combination of packing coefficients values, temperature, entropy and total volume factors.