| 摘要 |
PURPOSE:To improve magnetic property of ferrite without heat treatment after treating in a hot hydrostatic press, by a method wherein spinel amount is adjusted in the hot hydrostatic press so that oxygen amount in the primary burning product does not vary. CONSTITUTION:Iron oxide, manganese oxide, zinc oxide and the like are mixed at prescribed incorporating ratio in a ball mill. The mixture is filtered and dried and subjected to temporary burning in the atmosphere, and further ground by the ball mill into ferrite powders with particle diameter of 0.6mum for example. The ferrite powders are subjected to primary burning within the optimum oxygen equilibrium circumstance, and the primary burning product is adjusted in spinel amount and oxygen amount. Then treatment is performed in a hot hydrostatic press buried in powders having the same composition as that of the primary burning product so that oxygen amount in the primary sintered product does not vary. In this constitution, high-density ferrite is obtained in excellent magnetic property. |
