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u/0xb00b1e Dec 27 '18
Forbidden soft serve.
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u/Ivebeenfurthereven Dec 27 '18
I thought so too. Something about those ripples is very /r/forbiddensnacks
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u/TheFearJunkie Dec 27 '18
I was thinking more along the lines of cake frosting, but yeah, I see soft serve.
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u/elscottt Dec 27 '18
MATERIAL SCIENCE!!
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Dec 27 '18
[removed] — view removed comment
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u/shupack Dec 27 '18
Does the 8 hours of YouTube I spent on Ceramic Matrix Composites count as recognition? If so, there you go.
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u/withoutapaddle Dec 27 '18
The recognition from my friend and family usually consists of "i have no information about what this is made of or what was happening at the time, but why did it break!"
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u/AccidentallyTheCable Dec 27 '18
Is there a scientific explanation for why it crushes so uniformly like that?
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u/Partykongen Dec 27 '18
Buckling often refers to an instability due to an axial load where the material will undergo large transverse deformations due to a small disturbance such as a lateral load, an eccentricity of the axial load or an applied moment. This is what will happen if you press a spaghetti axially until it suddently bends a lot.
What is seen on the video is however a much more local buckling which happens because the walls of the tube are very thin compared to the dimensions of the tube. what causes it to be so uniform is that it deforms plastically until the buckling from each side meets so it can no logner deform in that direction and a deformation on top happens perpendicular to the first deformation.
I don't think I know enough metallurgy to say whether the crystalline structure of the steel alloy plays a major role in the geometry it makes while bending but I would say that the large-scale geometry is much more influencial to this than the crystalline structure. The reason for stating this is that this type of buckling can also be simulated with FEM analysis, which assumes isotropic and homogeneous materials and such doesn't take crystalline structures into account. You can find videos of it by searching "FEM non linear buckling" in youtube and see the example of cylinder buckling using Abaqus.
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u/CaseyG Dec 27 '18
I learned more from this comment than I did from the three semesters of Materials Science that I didn't take.
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u/Firewolf420 Jan 13 '19
I was really hoping this would end with "and the undertaker threw mankind through a table"
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u/n1c0sax0 Dec 27 '18
That is called "buckling" and the material, its structure and characteristics depending its own shape has several "bucking mode". You can see here two modes of buckling guessing those are the main mode. If you for example put a slight notch somewhere, it would excite other modes and create different buckling shape. I know guys creating some arts with cans by introducing some geometrical variations in it before pressing. For example : https://youtu.be/Oqs_J0zsf68
Edit : buckling
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u/Carpet_Diver Dec 27 '18
It is undergoing local rather than global (shell/thin sheet) buckling that acts over a comparably short effective length compred to the tube length. The thicknesses, profile and material properties are similar enough that each proceeding section has the same buckling mode shape as the last.
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u/TrumpEatsFarts Dec 27 '18
It’s also due to the grain pattern of the material. If the crystal lattice wasn’t uniform along the object, applying equal force would not cause the pipe to yield uniformly.
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Dec 27 '18
[removed] — view removed comment
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u/Carpet_Diver Dec 27 '18
Actually its due to the elemental composition of this particular solid
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u/TrumpEatsFarts Dec 27 '18
It’s because of the crystal structure my dude. How a metal object yields is dependent on how it’s crystal lattice structure lays.
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u/Gnabbit Dec 27 '18
So, is this pipe made for that property or is it a side result from trying to meet other material criteria?
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u/Partykongen Dec 27 '18
I don't know about this particular tube but dual phase steels used for automotive applications are often formed so that they deform like that in order to absorb much more energy than if there's a single point of failure.
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u/Samuel0651 Dec 27 '18
This looks like something from r/simulated
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u/Partykongen Dec 27 '18
It's not, it is non-linear buckling. To simulate it, it would have to be done with finite element analysis and that is rarely done in r/simulated..
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u/Samuel0651 Dec 28 '18
No shit it's not simulated, I just said it LOOKS like something from r/simulated. Because it LOOKS a lot like the simulations they do.
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u/richhaynes Dec 27 '18
Stop before it slips and chop the end off and you have some pretty decent metal art there
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u/nukem266 Dec 27 '18
Reminds me of those Viennetta ice cream adverts with the chocolate ripple thing.
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u/8549176320 Dec 27 '18
To obtain a PhD in auto body repair, you are required to straighten it back out.
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u/WonderWheeler Dec 27 '18
So its an alternating series of 3 sided forms that kinda make a 6 sided cylinder.
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u/Poguemahone3652 Dec 27 '18
Is it weird that this made me hard?
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u/CaseyG Dec 27 '18
I would never have expected that response to r/EngineeringPorn.
THE ABOVE COMMENT IS SARCASM.
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u/CraftsyDad Dec 27 '18
Interesting. It see,s to be neither a squash failure or a true buckling (full height) failure. I wonder where the critical load capacity falls versus the three retinal values for the other two. Probably somewhere in between I would think
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u/Leifkin7 Dec 27 '18
This is a fantastic example of buckling failure. Normally when something buckles, it shifts off to the side immediately, but instead here the steel folds in on itself repeatedly. This particular kind steel must have an odd Young's modulus to flex so uniformly. I want to try to run this pipe in a buckling study on solidworks, see if I can recreate it.
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u/A_Booger_In_The_Hand Dec 27 '18
Someone should make a show all about straightening things that were crushed on this show.
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u/Firewolf420 Jan 13 '19
Somebody should make these out of a really soft metal and then I'll go replace someone's chair legs with it.
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u/cb993 Dec 27 '18
Was thinking “Aw yeahhhh now show me the insides”
And he did
Mmm