Ferromagnetic metal powder

摘要

There is provided an accicular ferromagnetic metal powder with which one can produce magnetic media for high-density recording that are improved in storage stability and magnetic characteristics. The improved ferromagnetic metal powder essentially consists of iron and 50 atm % based on the amount of iron of cobalt and at least one of aluminum and yttrium or any other rare earth element and contains no more than 0.05 wt % of an element of Group Ia of the periodic table (Li, Na, K). The amount of aluminum is in the range of 0.1-30 atm %, the amount of yttrium or any other rare earth element is in the range of and 0.1-10 atm %, each being based on the total quantity of the metal elements present. In either of these cases, the residue of an element of Group IIa of the periodic table (Mg, Ca, Sr, Ba) is preferably 0.1 wt % or less.