As deformation proceeds the geometric instability causes strain to continue concentrating in the neck until the material either ruptures or the necked material hardens enough, as indicated by the second tangent point in the top diagram, to cause other regions of the material to deform instead. The amount of strain in the neck is called the natural draw ratio.  because it is determined by the material's hardening characteristics, not the amount of drawing imposed on the material. Ductile polymers often exhibit tense necks because molecular orientation provides a mechanism for hardening that predominates at large strains


23.45, 1.12.12. 

Necking results from an instability during tensile deformation when a material's cross-sectional area decreases by a greater proportion than the material strain hardens

Necking results from an instability during tensile deformation when a material's cross-sectional area decreases by a greater proportion than the material strain hardens. Three concepts provide the framework for understanding neck formation.

Before deformation, all real materials have heterogenieties such as flaws or local variations in dimensions or composition that cause local fluctuations in stresses and strains. To determine the location of the incipient neck, these fluctuations need only be infinitesimal in magnitude.

During tensile deformation the material decreases in cross-sectional area. (Poisson effect)

During tensile deformation the material strain hardens. The amount of hardening varies with extent of deformation.

The latter two items determine the stability while the first item determines the neck's location.

Graphical construction for a material that deforms homogeneously at all draw ratios.

The plots at left show the quantitative relation between hardening depicted by the curve's slope and decrease in cross-sectional area assumed in the treatment to vary inversely with draw ratio for a material that forms a stable neck top and a material that deforms homogeneously at all draw ratios bottom.

As the material deforms, all locations undergo approximately the same amount of strain as long as it hardens more than its cross-sectional area decreases, as shown at small draw ratios in the top diagram and at all draw ratios in the bottom. But if the material begins to harden by a smaller proportion than the decrease in cross-sectional area, as indicated by the first tangent point in the top diagram, strain concentrates at the location of highest stress or lowest hardness. The greater the local strain, the greater the local decrease in cross-sectional area, which in turn causes even more concentration of strain, leading to an instability that causes the formation of a neck. This instability is called "geometric" or "extrinsic" because it involves the material's macroscopic decrease in cross-sectional area

'Necking', in engineering or materials science, is a mode of tensile deformation where relatively large amounts of strain localize disproportionately in a small region of the material. The resulting prominent decrease in local cross-sectional area provides the basis for the name "neck". Because the local strains in the neck are great, necking is often closely associated with yielding, a form of plastic deformation associated with ductile materials, often metals or polymers


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it might really torture 
and hurt us  

eating 
gunpowder
testosterone oestrogen
ripple not really masochistic I 
mean what else are a girls hockey
muslces for a way on from Laibach ... 




23.17, 1.12.12. © Lizarikk, All Rights Reserved

I got really stuck in that ghost role 

holding the hand of my 'grandparent' 

I didn't like her to begin ... 

she asked me to cut the crap staring at the stars ...

where you think i got this from ... 



21.34, 1.12.12.  © Lizarikk, All Rights Reserved

where are my comments i am the subject of this article like hello do i get to eat any of the food i cooked 

Titangrip

01 December 2012 8:04 PMLink to this comment

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"highly personal and wilfully elusive "

ahhh the wank hour.

• ephemerid

  1 December 2012 8:27PM
  I'm aware that this has nothing to do with the cartoon - so please forgive me.

  There is an article by Shiv Malik, tucked away in the Politics section.

  It's about sick and disabled people being expected to work even though they have been judged unfit to do so by Atos/DWP. Some of us have been warning about this for a while now, but the new rules start on Monday. The article should, IMHO, be on the front page.

  Monday is also International Day for People with Disability.

  Never let it be said that irony is dead.

  Monday will also see campaigners and interested parties observing a two-minute silence at 11.00 hrs GMT to remember the victims of the draconian regime some of us live under.

  More information - atosvictimsgroup.co.uk or blacktrianglecampaign.org

  It would be nice to think that some of my friends here will join me in a moment or two of reflection on Monday for all those who have taken their own lives or died with no support.

  Thank you.
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• ucic

  1 December 2012 8:30PM
  Succinct and to the point CartoonistRowson... If only our so called political leaders had an ounce of your integrity and political ingenuity!
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• lightacandle

  1 December 2012 8:37PM
  Response to WellmeaningBob, 1 December 2012 7:39PM
  Not far wrong there Mr Wellmeaning One - as he showed when trying to continue the war theme on the home political front during his 1945 election campaigning...

  "Churchill's statement that Attlee's programme would require a Gestapo-esque body to implement is considered to have been particularly poorly judged"

  http://en.wikipedia.org/wiki/United_Kingdom_general_election,_1945

Katyia1 December 2012 8:11PM

our supposed prime minister in a cage of American
totalitarian dictatorship – - – meh – - – and that is
supposed to be the good puff – - -
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submitted

• Vordermont1 December 2012 6:07PM
  
  It shows who is the master.
  Rupert!!!
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• Katyia1 December 2012 8:13PM
  Response to Vordermont, 1 December 2012 6:07PM

  tad too much eye shadow there dear – - -
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sarcolemma

actually I don't really like talking about myself Ill just tell you all about you ... your thoughts your feelings your love life ... the time when I filmed you naked in your back garden .. ooooh that man .... my curtains went bonkers lol! In fact Ill tell you even more intimate detailed porn about the thumping thing I saw ... you and him ... the way you twitched and scratched ... ooohh ... let me write about youuuuu .... the black cat told me ... your body is an odd shape and full of interesting scars and injuries ... RRRRiiiibbbiiiiittt Im going to make a song about you .... 



10.11.12.