BEHAVIOR OF MAGNETIC PARTICLES IN COMPACTION

A purpose of this study is to perform a compaction process of ferromag netic powder for optimizing magnetic characteristics in producing magn etic recording medium or a permanent magnet. The magnetic powder is tr eated as an assembly of particles. A circular disk and an elliptical d isk are employed as particle models. To simulate the behavior of the p articles, a particle dynamics simulation is proposed, where Coulomb's law for magnetized particles, torque by an applied magnetic field, ela stic repulsive force due to Hertzian contact and friction force are co nsidered. A relationship between the direction of the applied magnetic field and motion of the punch is examined. It is commonly considered that easy directions of magnetiztion are oriented constantly in the di rection of an applied magnetic field. However, the simulated results s how that the particles are not aligned so because of the interaction f orces between the magnetized particles.