Magnetically hard films

Partially fluorinated X-IP has been used for a number of years as an additive in the inert lubricant PFPE film on the surface of a magnetic hard disk to enhance start/stop durability of PFPE lubricants [29,30]. Recently it has been used as a vapor lubricated film on the surface of the disks [31 ]. In order to avoid the PFPE being catalyzed to decomposition by the slider material AI2O3 (refer to Section 3.4), XI -P was also examined as a protective film on the surface of the magnetic heads [25,32]. The results of CSS tests indicate that the thermal stability of the lubricant was greatly improved in the presence of X-1P, and the thickness of X-1P film on the slider surface has an important influence on HDD lubrication properties. 

Magnetic hard discs are used in computers to store information in the form of magnetic bits on a ferromagnetic alloy film. To protect the magnetic medium, a hard carbon coating about... 

The substrate was also found to influence the properties of the electrolessly deposited vertical media CoNiMnP, CoNiReMnP, and CoNiReP. The c-axis orientation had a larger degree of perpendicular orientation for films deposited on electroless NiP than for those deposited on Cu foil, presumably because of the smaller roughness of the former substrate [43]. The double-layer (magnetically soft interface, magnetically hard bulk) properties of CoNiReP deposited on a NiMoP underlayer [57] have already been discussed. 

Gao, C. Lee, Y. C. Chao, J. Russak, M. Dip-Coating of Ultra-Thin Liquid Lubricant and Its Control for Thin-Film Magnetic Hard Disks. IEEE Trans. Magn. 1995, 31, 2982-2984. 

The hard disk of a computer exploits thin magnetic metal films with a present-day data storage capacity of about 10 Gb in-2 whereas in the case of flexible tape memory systems incorporating magnetic particles the capacity is about 100 times smaller. 

Ferrites can be classified according to crystal stmcture, ie, cubic vs hexagonal, or magnetic behavior, ie, soft vs hard ferrites. A systematic classification as well as some appHcations ate given in Table 1 (see also Magnetic materials, bulk Magnetic materials, thin film). 

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