Everything about Contact Mechanics totally explained
Contact mechanics is the study of the
deformation of
solids that touch each other at one or more points. The physical and mathematical formulation of the subject is built upon the
mechanics of materials and
continuum mechanics. The original work in this field dates back to the publication of the paper "On the contact of elastic solids" (
"Ueber die Berührung fester elastischer Körper"
) by
Heinrich Hertz in
1882. Hertz was attempting to understand how the optical properties of multiple, stacked
lenses might change with the
force holding them together. Results in this field have since been extended to all branches of engineering, but are most essential in the study of
tribology and
indentation hardness.
Introduction
Contact mechanics is an area of physics in which the motion of two or more bodies in space is restricted by additional constraints. These so called unilateral constraints ensure that bodies once coming into contact don't penetrate each other. Once the general equations for a contact problem are set up, different solution schemes can be used to simulate the behaviour of bodies in contact and to compute displacement and stress fields. There are several possibilities to classify contact problems. Generally contact with and without friction is distinguished.
In case of analytical solution methods for contact problems the following classification was introduced.
Contact may occur between bodies in two distinct ways. A
conforming contact is one in which the two bodies touch at multiple points before any deformation takes place (for example, they just "fit together"). The opposite is
non-conforming contact, in which the shapes of the bodies are dissimilar enough that, under no load, they only touch at a point (or possibly along a line). In the non-conforming case, the contact area is small compared to the sizes of the objects and the
stresses are highly concentrated in this area.
Such distinctions however don't have to be made when numerical solution schemes are employed to solve contact problems. These methods don't rely on further assumptions within the solution process since they base solely on the general formulation of the underlying equations. Besides the standard equations describing the deformation and motion of bodies to additional inequalities can be formulated. The first simply restricts the motion and deformation of the bodies by the assumption that no penetration can occur. Hence the gap
between two bodies can only be positive or zero
»
where
denotes contact. The second assumption in contact mechanics is related to the fact, that no tension force is allowed to occur within the contact area (contacting bodies can be lifted up without adhesion forces). This leads to an inequality which the stresses have to obey at the contact interface. It is formulated for the contact pressure
These results may themselves be superposed onto those given above for normal loading.
Further Information
Get more info on 'Contact Mechanics'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://contact_mechanics.totallyexplained.com">Contact mechanics Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |
