THERMODYNAMIC PROPERTIES OF LIQUID ALLOYS OF 3D TRANSITION-METALS WITH METALLOIDS (SILICON, CARBON AND BORON)

A survey of the experimental investigations of the thermodynamic functions of formation of liquid binary and ternary alloys of 3d transition metals (Tr-Cr, Mn, Fe, Co, Ni, Cu) with metalloids (Si, C and B) is presented. The thermodynamic data for 19 ternary (such as Tr-Fe-C, Tr-B-C, Tr-Si-C and Tr-Si-B) and 17 border binary systems are reviewed. The effects of the microheterogeneous structure of liquid binary and ternary alloys of iron and chromium with carbon and boron are described. The experimental data indicate the existence of attractive forces between unlike atoms in all systems studied. The cobalt-rich regions in Fe-Co-C and Co-Si-C melts, where athermal solutions exist and repulsive forces take place, are an exception. The correlation between structural parameters of the liquid metals and excess thermodynamic functions at infinite dilution is discussed. Model calculations of glass-forming tendency (GFT), based on the concentration dependence of the integral enthalpy of mixing and the stoichiometry of associates in liquid ternary systems, allow the range of glass formation to be estimated.