Alloy for Soft Magnetic Layer in Perpendicular Magnetic Recording Medium

摘要

A soft magnetic alloy for perpendicular magnetic recording medium excellent n saturation magnetic flux density, amorphousness and atmospheric corrosion resistance. The alloy is an Fe-Co based alloy and comprises Fe in an amount satisfying 0.25 to 0.65 of Fe/(Fe+Co) ratio, which is an atomic ratio of Fe and Fe+Co; Zr+Hf in an amount of 6 to 100 at %; Na+Ta in an amount of 0 to 2 at %; Al and/or Cr in an amount of 0 to 5 at %; and the balance Co and unavoidable impurities. A part of Zr and/or Hf can be replaced by B, provided that the amount of B to replace Zr and/or Hf is double in at % of the total amount of Zr and Hf to be replaced and that the total amount of Zr and Hf after replacement is 4 at % or more.