Mn-Zn系ソフトフェライトの磁気特性に及ぼす微量酸化物の添加効果 The Effect of a Small Amount Addition of Many Different Oxides on the Magnetic Property of Mn-Zn Soft Ferrite
The effect of a small amount addition of many different oxides on the various properties of Mn-Zn soft ferrite was investigated. 21 kinds of oxides were widely chosen in terms of melting temperature and cation radii ratio (α value) of iron to additives. After 100ppm of additive was respectively added to the starting materials of Mn-Zn soft ferrite, they were fired under a condition. Initial permeability (μi) and core loss were measured in the alternative magnetic field of 100KHZ.<BR>It was found that ti and core loss are improves by the addition of oxides with melting temperature of approximately 1, 000°C and a value of nearly 0.<BR>The solution mechanism was discussed based on the data showing relation between density and grain size. The oxides with α value of nearly 0 was responsible for interfering with the grain boundary migration, resulting the formation of a fine and uniform microstructure. Small pores were also put off by the grain boundary diffusion of mätrix materials during final sintering while the grain boundary migration was inhibited by the additives having a high melting temperature and suitable α value.
粉体および粉末冶金 43(8), 966-971, 1996-08-15
Japan Society of Powder and Powder Metallurgy