4/24/2002, Wednesday Surface Roughness

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4/24/2002, WednesdaySurface Roughness
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Fatigue Fracture
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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.
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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.
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Tribology
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Scale Dependent
Hardness
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Self-Similarity
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Etching
Micro-machining
Etching on the silicon wafer
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Chemical Potential
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Creep by Barriers on Dislocation Sliding
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Creep Barrier
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Model
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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
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Finger-print of surface residual stress