Surface characteristics in the precision grinding of Mn–Zn ferrite with in-process electro-discharge dressing

Mn–Zn ferrite is used as a material of hard disk magnetic heads, but is difficult to grind because of its high hardness and brittleness. Therefore, a super-abrasive diamond wheel is used for the precision surface grinding of this material. However, the conventional dressing method cannot be applied to a super-abrasive diamond wheel. This study describes a newly proposed method for carrying out effective in-process electro-discharge dressing (IEDD) of a super-abrasive diamond wheel. Using IEDD, the surface roughness of Mn–Zn ferrite was improved, and the grinding force was reduced. IEDD is a good method to obtain efficient grinding and surface grinding of ferrite.