Formation of iron borides and iron nitrides in interaction of iron powder with boron nitride powder

Abstract

ABSTRACTThe paper considers a way of iron nitrides production in monolithic specimens. The relevance for iron nitrides production is conditioned by the promise in using phase Fe16N2 (α’’-phase) as a hard-magnetic material due to the high value of the saturation magnetization (2.3 T at 4.2 K). By means of X-ray diffraction analysis, scanning electron microscopy, and magnetic parameter measurements, the study analyzes the structure and magnetic properties of metal alloy based on iron, obtained as a result of interaction between iron and boron nitride powders after their mixing, pressing, and heat treatment at 1550°C in the atmosphere of nitrogen. The heat treatment results in metal fragments exudation from the ceramic part of the briquette. The microstructure of the fragments is composed of primary deposited iron, eutectic colonies of Fe – iron boride type, and incorporation of iron nitrides. The obtained metal fragments are characterized by high coercivity (0.50 kOe).