4/24/2002, Wednesday Surface Roughness

Fatigue Fracture

Temperature distribution at Head-Disk Interface G.B. Sinclair Dept. of Mechanical Engineering, LSU Two half spaces represent a slider and moving disk, make contact through a rectangular patch. The model is used to generate representative statistics for the heat partition and temperature distribution at the interface. When two surfaces come into sliding contact, the friction heat produced at their contacting interface can lead to rapid temperature rises termed flash temperature. The determination of these temperatures, in general, is a subject of long standing interest and has received considerable consideration in the literature. Of specific interest here is the estimation of flash temperature in computer hard-disk drivers. These systems feature a slider carrying a head which reads/writes to a disk it flied above. Occasionally, the head makes contacts with the disk because of the extremely low flying heights at which it operates in present day drivers. The temperatures such incidences caused are of some concern to the data storage industry.

Thermal instability introduced by surface roughness M.M. Khonsari Dept. of Mechanical Engineering, LSU High speed sliding contact between nominally flat surfaces is generally associated with a significant frictional heat at the interface giving rise to a form of thermally induced damage where macroscopic areas of high temperature concentrations appear on the surface.

Tribology

Scale Dependent Hardness

Self-Similarity

Etching Micro-machining Etching on the silicon wafer

Chemical Potential

Creep by Barriers on Dislocation Sliding

Creep Barrier

Model

Chemical Potential for Etching in Strained Solid g is the surface energy density Curvature Strain energy difference w0 is the strain energy of flat surface

Finger-print of surface residual stress