Investigation of pecularities of the structure formation for Fe-B-C system alloys in crystallization

Abstract

Is show that in the iron-based alloys with weight content of boron from 1,8-3,5 % and with carbon content from 2-2,5 % (w.) after crystallization the morphology of specimen includes primary dendrites of Fe₃(CB) phase and plate-like eutectics γ-Fe+Fe₃(CB). It is revealed that in the process of Fe-B-C alloys crystallization the formation of cubic boron carbide Fе₂₃(CB)₆ takes place as a result of preannealing at the temperature of 1173 K. The formation of Fе₂₃(CB)₆ phase occurs on peritectic dissolving of Fe₂B boride, whereas eutectics Fе₂₃(CB)₆+γ-Fe is formed as a result of four-phase peritectic transformation L+Fe₂B→Fе₂₃(CB)₆+γ-Fe.