Thermodynamic Estimation of the Solidification of Borides and Carbides from Boron-Containing Iron–Carbon Melts

Abstract

Abstract—The probability of the formation of solid iron borides and boron and iron carbides from Fe–C–B melts is thermodynamically estimated. The Gibbs energy of a chemical reaction is taken as a criterion for the solidification of these phases. The following standard states are used: for iron, pure liquid iron; for carbides and borides, a pure solid at temperature T; for boron and carbon, a pure liquid supercooled (metastable) element. The results of experimental diagnostics of the structure and composition of experimental castings made of carbon steels with surface alloying with boron-containing components (ferroboron, boron carbide) are presented. The solidification of borides and carbides from the melts under study was shown to occur at high boron and carbon concentrations and low temperatures.