公开(公告)号：JPS6376306A

公开(公告)日：1988-04-06

申请号：JP22003586

申请日：1986-09-18

Applicant: AGENCY IND SCIENCE TECHN

Inventor： ITO TATSUO ,  HAYASHI NAOMI ,  KOSAKA MINEO ,  TAKAYANAGI TAKESHI

IPC: C01G49/00 ,  H01F1/34

Abstract: PURPOSE:To increase the saturation flux-density of a soft ferrite without deteriorating the high-frequency characteristic by a method wherein fine particles of an independent magnetic metal, e.g. high-purity iron, are dispersed in the continuous soft ferrite and are molded. CONSTITUTION:Iron powder is heated up to 530 deg.C in a flow of hydrogen, and impurity and oxide are removed from the particle surfaces. Then, water vapor is added to the hydrogen, and a thin film compsoed of Fe3O4 is formed on the surfaces of the iron particles. Then, an operation for co-precipitation is carried out at 70 deg.C by means of three solutions, i.e. a solution A whose mol ratio of nickel chloride, zinc chloride and ferric chloride are 0.5, 0.5 and 2.0, respectively, a solution B which contains sodium hydroxide at a concentration of 8 mol/1, and a dispersed solution C where the prepared and surface-treated iron powder is immersed and dispersed in a small amount of the solution B and kept for about one hour. Then, the ferrite component contained in the solution A is precipitated completely. Through an operation to add the dispersed solution C at the beginning, a sediment whose nucleus component is individual iron particles is precipitated. Through this constitution, it is possible to simultaneously satisfy the flux density and the high-frequency characteristic (this can be improved with the increase in the electric resistance) of a magnetic material.