Talk:Deformation (engineering)

Latest comment: 10 years ago by BioticPixels in topic Internal Inter-Molecular Forces

Merge with "Deformation mechanism map"

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I am wondering if someone with experience in this area can judge whether the page deformation mechanism maps can be merged with this one.--Nathan Clement 15:28, 24 September 2007 (UTC)Reply

I added merge tags as this has been an outstanding question for a long time, and given other discussions regarding this article (see Talk:Deformation (mechanics)) thought it should be resolved. David Hollman (Talk) 09:46, 8 September 2010 (UTC)Reply
Oppose: although the map article is brief, it is easy to imagine that with expansion it could stand as a topic on its own. David Hollman (Talk) 09:46, 8 September 2010 (UTC)Reply
Oppose - definitely deserves its own article in my view, there is a lot of information that could be incorporated into it, particularly from here. I won't promise to do it myself, although I may get round to it at some point. Mikenorton (talk) 14:59, 1 April 2011 (UTC)Reply
Oppose - I also feel that the should have its own article. Surely the article should show the standard looking diagram. Then the individual regions, along with the relavent strain rate equation should be presented. Jrwst36 (talk) 07:52, 8 July 2011 (UTC)Reply

Deformation of elastomers

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I removed "As the name implies, elastic (rubber) has a rather large elastic deformation range." from the elastic deformation section because it is questionable.

Elastomers (including rubber) clearly return to their original length after large deformations, however as stated in their article they have a very non-linear response to stress and elastic deformation is usually characterised by a linear response. I don't know enough to correct the statement but thought it should be removed until someone who does comes along. 137.205.78.240 (talk) 11:21, 21 April 2008 (UTC)Reply

elasticity is a measure of how much stress can be loaded onto a material without deforming it plastically. Since, elastomers can remain in the elastic deformation region at such large strains they are considered elastomers. The fact that their stress-strain curve is non-linear simply means that the Young's Modulus and Hooke's Law approximation does not apply to the stress-strain curve.
Summarizing, if the material can undergo high strains elastically, then it is an elastomer. The shape of the stress-strain curve has nothing to to with this.The Lamb of God (talk) 16:28, 15 September 2009 (UTC)Reply
I added back the information about rubber. David Hollman (Talk) 09:28, 8 September 2010 (UTC)Reply

Most and least elastic materials

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It would be useful if the page listed the most and least elastic materials. Whilst ceramics and crystals are listed as not very elasitic, which is the least of them all? I thought it might be diamond, but don't know if that is true. Hardness and elasticity are not the same, but I suspect there is some correlation between the two properties. Drkirkby (talk) 22:08, 11 June 2009 (UTC)Reply

More specifically materials would be referred to by their yield strength, tensile strength, or tensile ductility.
It would be easier to correlate hardness and brittleness. The onset of plastic deformation is at the point when the yield strength is breached, any deformation before the yield strength is reached is reversible and thus elastic. Since ceramics have such incredibly high yield strengths they tend to break from their brittleness long before they undergo plastic deformation, that is that they fracture by the propagation of preexisting cracks in the crystal structure. Materials that are softer have lower yield strengths but are able to deform plastically well before they fracture.
So, for the article to state that ceramics are not very elastic is misleading, they undergo almost only elastic deformation. In fact ceramics would simply be "not very plastic", as is mentioned, they would be very hard, and thus they would be very brittle.
So, the strict, more correct correlation is the harder the material the more brittle it is. This of course does break down with some more exotic materials. I will see if I can place up a table of yield strengths.The Lamb of God (talk) 16:20, 15 September 2009 (UTC)Reply

Low importance

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It's hard to see this subject is of low importance. It has a major impact on almost anything we buy or touch. —Preceding unsigned comment added by Drkirkby (talkcontribs) 22:11, 11 June 2009 (UTC)Reply

If Deformation in this context includes "elongation", by which I mean the engineering term, as in % elongation, then it is a fundamental mechanical engineering concept. Hardly unimportant. Materials are generally specified in tensile strength and elongation as well as hardness and others. Wiredrabbit (talk) —Preceding undated comment added 22:32, 15 December 2010 (UTC).Reply

Misconceptions Quote

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Do we have a source for this quote? I would be interested in hearing where it came from. Otherwise, does it make sense to have it in quotes if it's just something we made up? Practicality (talk) 14:42, 28 January 2010 (UTC)Reply

The quote is from Frank Herbert's Dune.
I've removed the quote because it's only loosely related and doesn't really add anything to the article. Wizard191 (talk) 18:30, 28 January 2010 (UTC)Reply
The new Ref. here is not very good here either. Especially it did not support the old text. The main part on the cited page is that glass can be very strong if it is free of surface defects.--Ulrich67 (talk) 20:05, 23 March 2012 (UTC)Reply

Internal Inter-Molecular Forces

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Does "internal inter-molecular forces" refer specifically to Intermolecular forces or actually include Intramolecular forces? It would also be helpful to add a link to the article for clarification. BioticPixels (talk) 22:37, 2 January 2014 (UTC)Reply