BARIUM-DOPED IRON-OXIDE PIGMENTS FOR HIGH-DENSITY MAGNETIC RECORDING - THERMAL-STABILITY AND MAGNETIC-PROPERTIES

被引：3

作者：

SARDA, C ^{[1
]}

BONINO, C ^{[1
]}

MOLLARD, P ^{[1
]}

ROUSSET, A ^{[1
]}

机构：

[1] LAB LOUIS NEEL,CNRS,F-38042 GRENOBLE,FRANCE

来源：

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS | 1992年 / 109卷 / 01期

关键词：

D O I：

10.1016/0304-8853(92)91041-Q

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Magnetic particles of barium surface-doped gamma-Fe2O3 and Co-gamma-Fe2O3 were prepared from oxalic precursors to obtain the required morphological and magnetic characteristics for high density magnetic recording. The role of the alkaline-earth ions was studied, especially as they affect morphological and magnetic characteristics, along with the thermal and chemical stabilities of the products. By several methods of analysis, it has been shown that Ba ions are located at the surface of the gamma-Fe2O3 (or Co-gamma-Fe2O3) particles. Thus the spinel lattice of the particle core, and the resultant magnetic properties, are not modified. Indeed, the evolution of coercive force and magnetization versus oxidation temperatures are comparable with those of free barium pigments. Barium doping also makes it possible to conserve the spinel lattice above 750-degrees-C, and the presence of Fe2+ ions (with high magnetocrystalline anisotropy) is observed up to 250-degrees-C.

引用

页码：127 / 132

页数：6

共 8 条

[1]

BERKOWITZ AE, 1968, J APPL PHYS, V39, P126

[2]

ROUSSET A, 1987, J CHEM RES-S, P140

[3] SIMULTANEOUS SUBSTITUTION OF CO-2+ AND ZN-2+ IONS IN SUBMICRONIC ACICULAR GAMMA-FE2O3 PARTICLES [J].