No abstract

To understand better the friction force and wear processes at contacting slider-disk interfaces, we have developed an experimental method for measuring and a theoretical method for calculating the friction force. For this study, a slider with a 1500 lm 2 contact pad located at the recording head is burnished against a relatively rough disk ( $ 12 Å rms), which ensures smooth sliding. In the experimental method, the friction force is measured as the disk is spun-down to bring the slider-disk interface into an increasing degree of contact. A modified air bearing code is used to determine the experimental normal contact force for each friction measurement. In the theoretical method, the friction force and other relevant interfacial forces are calculated using an improved sub-boundary lubrication (ISBL) rough surface model. The friction force calculation in this model is based on the force needed to induce yielding of the individual disk asperities contacting the flat surface of the contact pad without any assumption of the coefficient of friction. Good agreement is found between the measured and theoretical friction vs. normal contact force curves, indicating that the model is capturing the essential origins of friction at this interface. The model also provides valuable insights into how wear particles may be generated at this contacting slider-disk interface.

No abstract

No abstract

We have successfully designed, fabricated, and tested contact recording sliders where most of the suspension load is supported by an air-bearing surface with only a small contact force ( 5 mN) acting on the rear contact pad. To understand the contact dynamics, we have developed an integrated approach where experimental results from friction and laser doppler vibrometry are modeled using an air-bearing code modified to include contact forces. A low bounce ( 1 nm mean-to-peak) is achieved in our designs by reducing the real area of contact to minimize friction, by increasing disk roughness, and/or by reducing the width of the slider contact pad. Due to the reduced magnetic spacing, these contact recording heads have bit-error rates several orders lower than conventional flying heads.