Abstract
The effect of the structural state and the phase composition on the magnetic hysteresis properties of Fe(95)C(5) and Fe(85)C(15) powders after mechanical alloying and annealing is investigated. It is shown that in the initial stage of grinding in a ball planetary mill the coercive force of the Fe–C powders is determined by the degree of defectiveness of the α-Fe phase and the relative volume and dimensions of nonmagnetic graphitic inclusions in iron powder particles. As the grinding time increases, the α-Fe phase goes over into a nanostructure state and carbon from graphite inclusions goes over into an amorphous Am(Fe–C) phase. After annealing on the temperature interval 300–600°C, the amorphous Am(Fe–C) phase is transformed into Fe3C ferric carbide. The coercive force of the Fe3C phase strongly depends on the degree of distortion of its crystal lattice and amounts to ∼ 80 A/cm for the phase with distorted lattice and ∼ 240 A/cm for the phase with equilibrium undistorted lattice. The magnetic characteristics of the powder after mechanical alloying and subsequent annealing are determined by the type, amount, and structural state of the phases containing in the samples.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call