PURPOSE: To attain both the improvement of the performance of a magnetic head and the variance decrease of the performance by controlling the surface roughness of an auxiliary core which is made to a ground basic plate of a main core.
CONSTITUTION: Ferrite is used for the auxiliary cores 1, 1' and a main core 2 is a metallic magnetic material and constituted of an amorphous alloy or the like and formed by a means such as the sputtering or the vacuum vaporization. The material wherein a metallic magnetic film becoming the main core 2 is stuck on at least one side of the auxiliary cores 1, 1' is bonded by fusing glass 5 so as to form a magnetic gap 6. The auxiliary cores 1, 1' being a ground basic plate for forming the main core are abraded and processed by rotating the following blade in the ultrahigh velocity wherein the diamond lapping powder is used in a high-precision spindle for an adhered surface of the magnetic film becoming the main core 2 or processed in the surface roughness better than 0.8s by using a lapping machine and lapping the adhered surface with 3μm lapping powder. When the lapping powder is ≤3μm particle size, the surface roughness suitable for the coating of the magnetic film can be obtained.
MORIKAWA JUICHI
ISHIHARA KIYOSHI
KAJIYAMA MORIO
