Talk:Poisson's ratio

message: Can someone tell me what strain measure is used in the graph showing small vs. large deformation lines for the large deformation formula? - EndingPop 18:18, 18 March 2007 (UTC)
replies: text: small deformations assumes that strain is linear (the first derivative is a constant number), large deformation assumes that the strain is not linear (depending on the precision is it not constant up to second or larger "n-th" derivative). If you are talking about "Engineering strain", "true strain", "logarithmic strain" or "lagrange strain" then it is of no importance here: this plot could apply to any of them. The point is that whether you represent strain deformation using a linear or non-liear (more precise) function. Janek Kozicki 20:40, 19 March 2007 (UTC)
replies: text:  Your version is correct.  Bbanerje (talk) 22:07, 25 December 2016 (UTC)
thread_title:  Large Deformation Formula 

message: this should be mentioned. maybe
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Orthotropic means it is different in different directions.  Isotropic means it is the same in all directions.  Isotropic equations would be found under the generalize section.--thegreatco (talk) 17:48, 14 May 2008 (UTC)
thread_title: arnt the eqns under orthotropic material true for isotropic?

message: The definition given is in terms of strain in the transverse direction. But is that the average strain in the plane orthogonal to the stress, or what? —BenFrantzDale 07:14, 20 October 2005 (UTC)
thread_title: Area?

message: G is actually the Shear Modulus, a materials resistance to a change in shape without a change in volume. G is equal to shear stress, tao, over shear strain, gamma.
Tom Harrison Talk 19:50, 24 May 2006 (UTC)
thread_title: Moved from article

message: References would be good for the values listed for various materials. — DIV (128.250.204.118 05:59, 14 May 2007 (UTC)
thread_title:  References 

message: The Poisson Conspiracy! http://home.messiah.edu/~tvandyke/podcast5.mp3
153.42.211.95 18:44, 5 October 2007 (UTC)
thread_title: A bit of humor

message: The result was merge POISSON'S EFFECT into POISSON'S RATIO.  The merge was proposed almost two months ago (on 19th March).  All opinions (the four expressed below and the one of the user who initially proposed it) are in favor of the merge. -- Federico Grigio, alias Nahraana (talk) 17:54, 25 April 2008 (UTC)
replies: text: You say the page has good stuff and that you want it to be merged.  Now, what is the reason why it should be merged?  Federico Grigio, alias Nahraana (talk) 08:08, 1 May 2008 (UTC)
replies: text:  They should be merged because they cover the same topic. Together they contain more details than either one, but the effect and the ratio go hand in hand; the ratio is just a measure of the effect. —Ben FrantzDale (talk) 13:08, 1 May 2008 (UTC)
replies: text:  I see.  I agree to merge the articles, because of the same reasons as above.  Federico Grigio, alias Nahraana (talk) 08:34, 5 May 2008 (UTC)
replies: text:  I agree, they should be merged.  They are taught as one in all my engineering courses.  The ratio is the measure of the effect. thegreatco (talk) 17:22, 6 May 2008 (UTC)
replies: text:  Merge it. Greg Locock (talk) 01:58, 12 May 2008 (UTC)
replies: text:  I'll be honest, I've never merged a page and I don't think Poisson's Ratio is the place to start. --thegreatco (talk) 17:44, 14 May 2008 (UTC)

text: After we finish the merge (when all content has been removed from Poisson's effect) we can place #REDIRECT Poisson's ratio on it.  Federico Grigio, alias Nahraana (talk) 11:35, 15 May 2008 (UTC)
thread_title:  Merge 

message: I made a slight modification to distinguish between pre-yield and post-yield deformation. This is strongly related to mods I made earlier today on the Necking(engineering) page. Also made it slightly less metals-centric. Crosslink (talk) 22:37, 16 February 2009 (UTC)
thread_title: Added distinction between pre-and post-yield behavior

message: The definition given in the main article refers only to tensional forces (ie: stretching). George Davis (Structural geology) defines it as "the degree to which a core of rock bulges as it shortens" under compression.Iain  —Preceding unsigned comment added by 41.0.29.98 (talk) 10:45, 23 October 2009 (UTC)
thread_title:  Definition of Poissons Ratio 

message: Some users have been changing the equations for orthotropic and transversely isotropic materials without understanding the significance of the quantities.  These equations can be written in many ways.  However, the definitions of the quantities in the equations must be consistent throughout the article.  They are consistent as of now. For example, changing
\nu_{xy}/E_x to \nu_{xy}/E_y changes the meaning of \nu_{xy}.  The new meaning is non-standard and a explanation has to be given on why such a menaing has been chosen.  Also, that change in meaning has to be reflected throughout the article, including in places where various Poisson's ratios of composites have been listed. Please discuss your reasons for changing these equations before going ahead with the changes. Bbanerje (talk) 22:04, 15 February 2010 (UTC)
thread_title:  Changing the equations for orthotropic and transversely isotropic materials 

message: Try again from above: Allowable range of ν
It would be useful to have a short section that identifies the allowable range of ν, which is -1 to 1/2, based on the equation 3B(1-2ν) = 2G(1+ν)
132.250.22.8 (talk) 20:26, 6 October 2010 (UTC)
thread_title:  Allowable range of ν 

message: Is it me, or does the "cause" part simply restate the effect, without explaining the underlying mechanism? To me it reads as "Materials exhibit the Poisson effect because their molecular structure exhibits the Poisson effect." Could someone give a clearer explanation of why this happens?
TheCat5001 (talk) 10:16, 3 February 2011 (UTC)
thread_title:  Cause of the Poisson effect 

message: "For isotropic materials we can use Lamé’s relation"
However the linked wiki doesn't mention "Lamé’s relation" or the relation of this page.
Not sure which to clean up, though...71.29.179.72 (talk) 18:53, 15 October 2020 (UTC)
thread_title:  Lame's relation