High coercivity hard disk with CoCrPtB/Cr media

An investigation was made into material concentration of magnetic media used in hard disks to obtain higher coercivity. It was found that a slight addition of B in the magnetic layer of already known CoCrPt/Cr media could increase the coercivity significantly, to 3000 Oe or more. X-ray diffraction analysis indicates that coercivity increase by the added B element is caused by an intensified FCT