| 摘要 |
PURPOSE:To obtain a magnetic oxide material having crystal structure desirable as magnetic medium particles by adding an alkali to a soln. contg. metallic salts of Fe, Ba in a specified molar ratio to Fe and a specified metallic element in a specified molar ratio to Fe and reacting them under high pressure. CONSTITUTION:A soln. is prepared contg. metallic salts of Fe, Ba in 1/12-3/12mol ratio to Fe and a merallic element with average valency of 3 such as Co, Zn, Ti or Ge except Ba and Fe in 1.0/12-1.8/12 molar ratio to Fe. To the soln. is added an aqueous soln. of an alkali such as sodium hudroxide in an amount 1-5 times as much as the total amount of the metallic salts by equivalent, and they are reacted at >=400 deg.C in an autoclave to obtain a magnetic oxide material having magnetoplumbite type crystal structure, a large quantity of saturation magnetization, superior coercive force, etc. |
