An Asperity Contact Model for the Slider Air Bearing

Abstract

As sliders fly closer and closer to the disks, asperity contact is inevitable due to the roughness on the sliders and the disks. A single asperity contact problem was solved using the molecular gas-film lubrication (MGL) model with the no-fly-zone (NFZ) condition, which was discovered with the direct simulation Monte Carlo method (DSMC). It shows that the MGL model can also provide bounded pressure and resultant force in the presence of contact. Moreover, the MGL results agree well with the DSMC results. A database for a single asperity contact force and moment was then created using the MGL model with the NFZ condition. This force and moment was superimposed to the air bearing force calculated by the MGL model calculated by the MGL model when the nominal plane of the slider and the disk are not in contact. The total additional air bearing force due to asperity contact was obtained. Its effect on the slider’s flying attitude was investigated and found to change the flying height and pitch angle up to 20 percent and 10 percent, respectively. [S0742-4787(00)02402-4]