Studies stresses where bodies touch, as in Hertzian contact of gears and bearings.
Hertz contact theory gives contact area and pressure for curved bodies, e.g. two spheres: a=(3FR/4E*)^{1/3} with peak pressure p₀=3F/(2πa²). Subsurface shear stress drives rolling-contact fatigue (pitting) in bearings and gears.
A ball bearing's contact pressure can exceed 2 GPa.
Contact mechanics explains how stresses build up where surfaces touch, which controls wear, fatigue and failure in gears and bearings.
Studies stresses where bodies touch, as in Hertzian contact of gears and bearings.
Contact mechanics explains how stresses build up where surfaces touch, which controls wear, fatigue and failure in gears and bearings.
A classical solution for stresses between two curved elastic bodies, giving a contact area and a peak pressure that depends on the load and radii.
Surface fatigue and pitting start at the contact zone, which is why gear design checks contact stress as well as bending.
Typical applications include estimating the contact stress between two gear teeth, sizing a rolling bearing race for a given load and checking the pressure under a ball joint in a suspension.
Study "Multibody dynamics" first (topic 103 of 106 in Engineering Mechanics). It covers the groundwork this topic builds on.
Very high local stress. Elastic deformation of surfaces. Lubrication reduces friction.
A ball bearing's contact pressure can exceed 2 GPa.
The next topic is "Fatigue life prediction", which builds directly on this one.
It is classed as Advanced in Engineering Mechanics (topic 104 of 106). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Engineering Mechanics.
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