Abstract: A method is described for testing for slider/disk contact in a disk drive comprising a rotating disk and a head mounted by an actuator for selective positioning of the head over the disk, the head having a slider, and a spindle motor for rotating the disk. The method comprises the steps of providing power to the spindle motor to cause rotation of the disk at a preselected rotational velocity corresponding to a rotational velocity designed for the disk during normal read/write operation, and thereafter withdrawing the power from the spindle motor such that the disk spins down to zero rotational velocity. While the disk spins down to zero rotational velocity, an acoustic coupling is formed between an acoustic emission sensor having an electric output and the spindle motor to provide first electric signals representative of acoustic emissions from the spindle motor, including acoustic emissions caused by slider/disk contact.

Abstract: A method is shown for testing a magnetic disk to be used in a disk drive. The method includes the steps of measuring a height profile of an outer radial edge of the disk, using the profile to determine a slope value for each of a pair of radial segments of the disk, calculating a difference value between the slope values of the pair, comparing the difference value to a preselected threshold difference value and indicating when the difference value is equal to or less than the threshold difference value. The threshold value indicates an outer most diameter of the disk where fly height operation for a head is still stable.

Abstract: A disk drive having a read/write head flying at extremely low flying heights, the drive including a disk clamp for clamping one or more disks within the disk drive, with the clamp exerting a substantially uniform pressure at the circular line of contact between the clamp and the disk. The disk clamp includes a raised circular wall around an outer radius of the clamp, which wall is formed as part of and integrally with the rest of the clamp. The wall serves to increase the structural rigidity of the clamp in a single axial section of the clamp, thereby providing a "stress barrier" to the transmission of localized stresses from the screw points. Thus, the pressure exerted by the clamp on the disk is evenly distributed around the entire clamp, and the distortion normally occurring at the inner diameter of the disk with conventional disk clamps is greatly reduced.

Abstract: Carbon is sputter-deposited as a protective overcoat on the coating of a magnetic recording disk of the type in which the coating includes magnetic particles dispersed in an organic binder. The carbon film exhibits excellent durability and lubricity, thereby eliminating the need to incorporate alumina or other load-bearing particles into the magnetic coating, and eliminating the need for a liquid lubricant on the disk surface.