Investigation of head saturation using a large scale ferrite model head

Abstract

In order to investigate the head saturation which is observed in the recording process using a recording media with a high coercivity exceeding 500 Oe, the magnetic field distribution around the gap in the saturated condition is investigated using a large scale ferrite model head. The gap field gradually saturates by increasing the ampere-turns applied to the coil. When the flux density in the gap approaches the saturation flux density of the core material, the shape of the field distribution around the gap changes from semicircles, in the saturated condition, to arcs. Therefore, as the gap field in the saturated range increases, the rate of decrease, in the longitudinal direction of the recording field becomes more gradual. These phenomena will cause the effects similar to the head-tape spacing and expansion of the gap length in the recording process.