Hitachi Global Storage Technologies Netherlands B.v.

Malika Dothresa Carter

Bruno Jean Marchon

John Martin Burns

Michael Andrew Parker

Xing-Cai Guo

Thomas Edward Karis

Robert Waltman

Vladimir Nikitin

Wen-Chien David Hsiao

Ullal Vasant Nayak

Stanley Yen Wong

Christian Rene Bonhote

Kunihiro Shida

John W Lam

Yun-Lin Hsiao

Christopher Ramm

Wong K Richard

David A Dudek

A polishing system and associated methods are described for polishing a magnetic disk used in a disk drive system. The polishing system includes a polishing film that is used to polish the magnetic disk. The polishing system also includes an actuator operable to move the polishing film across a surface of the magnetic disk to polish the magnetic disk. The polishing system also includes a pad having at least one protrusion extending from a surface of the pad. The protrusion is configured to contact the polishing film and press the polishing film against the magnetic disk. The protrusion is operable to compress to about the surface of the pad when in contact with the polishing film. Once polishing is complete, the pad retracts from the polishing film and the protrusion extends from the pad, reducing the adhesion force between the pad and the polishing film.

Systems and methods for polishing a magnetic disk

Lubricant with non-terminal functional groups. The location of the functional groups minimizes free chain length and molecular weight of a lubricant while simultaneously maximizing evaporation temperature. The locations of the functional groups to the backbone of the molecule of the lubricant allows for shorter lengths of free backbone length between functional groups attached to a lubricated surface. The lubricant lubricates mechanical devices including hard disk drives.

Lubricant with non-terminal functional groups

A magnetic read/write head is produced with an insert layer between the substrate and the magnetic transducer. The insert layer has a lower coefficient of thermal expansion than the substrate, which reduces the temperature pole tip recession (T-PTR) of the head because the insert layer is an intervening layer between the substrate and magnetic transducer. The insert layer is produced by plating, e.g., an Invar layer over the substrate prior to fabricating the magnetic transducer. The Invar layer is annealed and the structure planarized prior to depositing a non-magnetic gap layer followed by the fabrication of the magnetic transducer.

Method of forming a magnetic read/write head

A system and method for reducing corrosion in a fluid dynamic bearing is disclosed. In one embodiment, a fluid dynamic bearing comprising a rotor portion and a stator portion is formed. In addition, a corrosion inhibitor containing lubricating fluid is provided between the rotor portion and the stator portion of the fluid dynamic bearing, wherein the corrosion inhibitor containing lubricating fluid does not react with either the rotor portion or the stator portion of the fluid dynamic bearing.

Fluid dynamic bearing comprising a lubricating fluid having tolutriazole

The invention provides a set of standards for accurately calibrating a vacuum thermogravimetric analyzer (VTGA). The invention solves the problem of calibrating a VTGA by using the actual magnetic transitions and associated transition temperatures, or Curie temperatures, T's, of a set of standards which can be used in-situ at the location of the sample holder obviating the difficulties associated with indirect methods of calibration. The set of standards permits accurate calibration through sufficiently numerous calibration points over a rather limited low-temperature range for determining vapor pressures of compounds. The set of temperature calibration standards is fabricated from slugs of ferromagnetic material. The composition of the ferromagnetic material in each slug is altered by alloying a ferromagnetic constituent with a non-ferromagnetic constituent to provide a plurality of standards with different Curie temperature over the limited temperature range. In particular, an embodiment of the invention using alloys of Ni and Cu where the amount of Cu varies between less than 0% up to approximately 50% by weight provides a set of standards that can span temperatures in any selected range from approximately 300 C to &#x2212;150 C respectively. Prior to use in calibration, each slug is preferably placed in a magnetic field having a magnitude sufficient to provide a well defined magnetic transition at the Curie temperature.

Standards for the calibration of a vacuum thermogravimetric analyzer for determination of vapor pressures of compounds

The invention provides a method for accurately calibrating a vacuum thermogravimetric analyzer (VTGA). The invention solves the problem of calibrating a VTGA by using the actual magnetic transitions and associated transition temperatures, or Curie temperatures, T's, of a set of standards which can be used in-situ at the location of the sample holder obviating the difficulties associated with indirect methods of calibration. The invention encompasses a method of using a set of calibration standards comprised of a plurality of ferromagnetic slugs to provide a temperature calibration for a VTGA. The method permits accurate calibration through sufficiently numerous calibration points over a rather limited low-temperature range for determining vapor pressures of compounds. Through the use of these standards, highly accurate measurements can be made of the vapor pressures of critical hard disk drive compounds, such as lubricants, and corrosion inhibitors, that are crucial to competitive disk drive technology.

Method for calibrating a vacuum thermogravimetric analyzer for determination of vapor pressures of compounds

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San Jose, CA, United States of America

Malika Dothresa Carter