Polycrystalline ferrite and a magnetic head using the same

摘要

A polycrystalline ferrite containing Na, Zr and Ca in amounts of 0.01 to 0.5% by weight, 0.005 to 0.5% by weight and 0.01 to 0.5% by weight respectively, in Mn-Zn or Ni-Zn ferrite to thereby enhance the toughness of said ferrite. Said ferrite is suited for a magnetic head with improved mechanical strength and excellent fine workability.