|WikiProject Physics||(Rated B-class, High-importance)|
In my opinion the page is too technical, I added the technical template to the top of the page.
- The introduction is quite long, and already contains a lot of details. It might try to focus more on the essential ideas.
- The distinction between non-adhesive and adhesive contact might be introduced separately.
- Classical solutions could be an entire top-level section by itself.
- Analytical and numerical solution techniques could also be discussed separately.
- The purposes, strengths and weaknesses of the various adhesive contact theories could be introduced in more general terms, before the theories are discussed in detail.
Line contact on a plane section
I think the integral formulas given in line contact on a plane section are incorrect. The dimensions don't match. Can someone confirm? I was reading contact mechanics by johnson and the formulas look a little different there. User:Blooneel 24 June, 2010
- Johnson's book assumes a left-handed coordinate system with the -axis pointing down. The results given in this article assume that the -axis points up. That leads to the different relations. See Barber's book on elasticity for the form given in this article. Bbanerje (talk) 03:45, 25 June 2010 (UTC)
I am wondering about the coordinate system in the Chapter "Loading on a Half-Plane". The coordinate z seems to be the direction normal to the surface (as also in the chapter before). Does this chapter present a 3D solution for a point load given in the plane y=0? Than the term "Loading on a Half space" would be better. Or is a plane strain (plane stress) solution presented?
In any case: the appearance of the y coordinate in the figure ( (x,y) and σy ) is misleading. For the same reason y should also be replaced by z in the sentence following the formulae : "for some point, (x,y), in the half-plane. " B Sadden (talk) 14:57, 30 May 2009 (UTC)
Error in sphere on half-space?
I may be wrong, but I believe that there is a mistake here; the radius of the contact area is quoted as being sqrt (R * d), I think (from a bit of cursory mathematics) that is should actually be sqrt (2 * R * d), can anyone confirm this, I may be mistaken so I won't change this unless someone else confirms...
- The Hertz solution for the elastic displacements in the region of contact is
- where are coordinates of the contact surfaces projected on to the -plane. For a circular contact area with radius ,
- If the second surface is a half-plane, and we have
- where is the radial distance to a point in the contact region from the center of contact. The Hertzian pressure distribution
- leads to the displacement field
- Plugging these into the relation for gives
- For plugging in the expression for gives
- Bbanerje (talk) 00:00, 28 July 2010 (UTC)
Error in rigid conical indenter and an elastic half-space?
The German Wikipedia has a and d switched in this formula: . And indeed, if one lets theta get towards 90° then only the switched version makes sense (radius gets towards 0). Peterthewall (talk) 17:55, 28 February 2013 (UTC)
Hertz Model for Sphere on Plane is Parabola Approximation
I would like to point out that the sphere on a plane section is for a parabola. Many make the no-slip assumption for a spherical indenter so they can approximate the sphere for a parabola. JPK instruments has a decent read on this in terms of AFM on cells: www.jpk.com/jpk-app-elastic-modulus4.download.5fb2f841667674176fd945e65f073bad
They have the sphere on
where a=(R*d)^1/2 (I think) E is Young's Modulus v is Poisson's Ratio d is indentation of plane I think it would be good to at least state somewhere that it is an approximation. — Preceding unsigned comment added by EvanN90 (talk • contribs) 21:24, 8 September 2015 (UTC)