Abstract: A cylindrical part of a rotor for an eddy current deceleration device of the present embodiment has a chemical composition consisting of, by mass %, C: 0.05 to 0.15%, Si: 0.10 to 0.40%, Mn: 0.50 to 1.00%, P: 0.030% or less, S: 0.030% or less, Mo: 0.20 to 1.00%, Nb: 0.020 to 0.060%, V: 0.040 to 0.080%, sol. Al: 0.030 to 0.100%, B: 0.0005 to 0.0050%, N: 0.003 to 0.010%, Cu: 0 to 0.20%, Ni: 0 to 0.20%, Cr: 0 to 0.10%, and the balance: Fe and impurities, and in which the total area fraction of martensite and bainite in a microstructure is more than 95.0%, and the number density of carbides having an equivalent circular diameter of 100 to 500 nm is 0.35 to 0.75 particles/?m2.

Abstract: Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium that has a magnesium (Mg) trapping layer that is configured to mitigate Mg migration in the HAMR medium so as to prevent near field transducer (NFT) damage caused by dissociated Mg reacting with a compound used in the NFT. In one example, the HAMR medium can include a substrate, a seed layer on the substrate and including MgO, a magnetic recording layer on the seed layer, and a Mg trapping layer on the substrate and configured to mitigate Mg migration from the seed layer to a surface of the HAMR medium above the magnetic recording layer.

Abstract: Disclosed herein is a magnetic storage device that comprises a housing defining an interior cavity. The magnetic storage device also comprises at least one magnetic disk in the interior cavity of the housing. The magnetic storage device further comprises at least one read-write head in the interior cavity and configured to read data from and write data to the magnetic disk. The read-write head comprises a heat-assisted magnetic storage (HAMR) head. The magnetic storage device additionally comprises a gas, comprising oxygen and helium, sealed in the interior cavity of the housing. A percent concentration of oxygen in the gas is greater than or equal to 3%. A pressure of the gas is between 10% and 70%, inclusive, of atmospheric pressure. A relative humidity within the interior cavity is less than 5%, inclusive. A percent concentration of helium in the gas is less than or equal to 90%.

Abstract: Embodiments of the present invention help to accomplish accurate and reliable clearance control. In one embodiment of the present invention, a disk drive device adjusts the clearance between a head element portion and a disk with a heater on a slider. The clearance control according to the present embodiment incorporates the variation in heater power efficiency in the clearance variation depending on the radial position. The clearance variation in a unit of heater power varies depending on the radial position. Taking account of the variation in the heater power efficiency in the thermal fly-height control (TFC) depending on the radial position in addition to the clearance variation between the head element portion and the disk caused by variation in fly-height or attitude, accomplishes more accurate TFC.

Abstract: Embodiments of the present invention help to accomplish accurate and reliable clearance control. In one embodiment of the present invention, a disk drive device adjusts the clearance between a head element portion and a disk with a heater on a slider. The clearance control according to the present embodiment incorporates the variation in heater power efficiency in the clearance variation depending on the radial position. The clearance variation in a unit of heater power varies depending on the radial position. Taking account of the variation in the heater power efficiency in the thermal fly-height control (TFC) depending on the radial position in addition to the clearance variation between the head element portion and the disk caused by variation in fly-height or attitude, accomplishes more accurate TFC.

Abstract: Troubles caused by contaminants in a magnetic disk apparatus are prevented by providing a monofunctional compound in a gas phase in the magnetic disk apparatus, said compound capable of undergoing polymerization reaction with hydroxyl groups present on the protective overcoat surfaces of a magnetic head and a magnetic disk and further capable of reacting with contaminants, thereby attaining a high reliability of the magnetic disk apparatus.

Abstract: Troubles caused by contaminants in a magnetic disk apparatus are prevented by providing a monofunctional compound in a gas phase in the magnetic disk apparatus, said compound capable of undergoing polymerization reaction with hydroxyl groups present on the protective overcoat surfaces of a magnetic head and a magnetic disk and further capable of reacting with contaminants, thereby attaining a high reliability of the magnetic disk apparatus.

Abstract: A skin depigmental agent characterized by comprising a resorcinol derivative having a linear alkyl group is provided.