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The Squid's Beak May Revolutionize Engineering

kdawson posted about 6 years ago | from the fortuitous-gradient dept.

Science 79

Ace905 writes "For years the razor-sharp beak that squid use to eat their prey has posed a puzzle to scientists. Squid are soft and fragile, but have a beak as dense as rock and sharp enough to break through hard shells. Scientists have long wondered why the beak doesn't injure the squid itself as is uses it. New research has just been published in the the journal Science that explains the phenomenon. One of the researchers described the squid beak as 'like placing an X-Acto blade in a block of fairly firm Jell-O and then trying to use it to chop celery.' Careful examination shows that the beak is formed in a gradient of density, becoming harder towards the tip end. Understanding how to make such hardness gradients could revolutionize engineering anywhere that 'interfaces between soft and hard materials [are required].' One of the first applications researchers envision is prosthetic limbs."

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79 comments

Beaks are neat (5, Interesting)

RockModeNick (617483) | about 6 years ago | (#22908186)

Puffer fish also have a shell-crushing beak attached to a relatively soft base, but they have the advantage of a jaw bone(thought they lack skeletal structures like ribs) to propel it. It still always amazed me how they managed to have such soft lips and skin and yet chew apart snails and other hard shelled foods so fast.

Re:Beaks are neat (0)

Anonymous Coward | about 6 years ago | (#22908714)

Soft lips and skin? Say no more, please!

Re:Beaks are neat (2, Funny)

Profane MuthaFucka (574406) | about 6 years ago | (#22909410)

Indeed. The puffer fish is not as well known as its cousin, the Babel Fish, but that should not let you from putting a puffer fish into your pocket and letting it get to work. You'll find that the puffer fish is a far better master of the sensual arts, and you'll not again be tempted by a blow job hamster which is, as I am sure you will agree, too little endowed in the lips, and to much endowed with the teeth.

Re:Beaks are neat (2, Interesting)

RockModeNick (617483) | about 6 years ago | (#22910220)

Check out the picture if you've got a strong stomach. http://floridakeystreasures.com/diving/puffer.shtml [floridakeystreasures.com] I can't think of a worse creature to make that particular request of... the blowjob hamster, while also terrible(and I hate hamsters, things bite me all the time at work) at least couldn't bite the thing clean off through a Kevlar condom. My green spotted puffer Shakespeare has nibbled my fingers on accident, too, he's only about an inch in length from being able to take bites of me.

Re:Beaks are neat (1)

FiestaFan (1258734) | about 6 years ago | (#22916514)

and I hate hamsters, things bite me all the time at work
Yeah I know what you mean, I hate people, things bite me all the time at work

Re:Beaks are neat (0)

Anonymous Coward | about 6 years ago | (#22909556)

It still always amazed me how they managed to have such soft lips and skin and yet chew apart snails and other hard shelled foods so fast.

I have wondered about that exact phenomenon almost every day since I was 16 years old. I've been testing a theory that the snails just need to make harder shells, but the mutation seems to be surprisingly maladaptive.

Re:Beaks are neat (0)

Anonymous Coward | about 6 years ago | (#22909564)

This is an interesting discovery, and I am sure there will be some practical applications, though I don't think it qualifies as "revolutionary."

No comments? (5, Funny)

Lordfly (590616) | about 6 years ago | (#22908212)

A front page article with no comments? Really? ...are you all having sex or something?

Re:No comments? (5, Funny)

Anonymous Coward | about 6 years ago | (#22908666)

Individually, yes.

Re:No comments? (1, Insightful)

Anonymous Coward | about 6 years ago | (#22908678)

I'm still trying to reconcile:

Understanding how to make such hardness gradients could revolutionize engineering anywhere that 'interfaces between soft and hard materials [are required].'

with

The Squid's Beak May Revolutionize Engineering

Re:No comments? (0)

Anonymous Coward | about 6 years ago | (#22908790)

You must be new around here.

Re:No comments? (1)

jollyreaper (513215) | about 6 years ago | (#22909538)

A front page article with no comments? Really? ...are you all having sex or something?
Farm-fresh prairie squid. Gotta remember to pull the ethereal beak first cuz that's a mistake you can't make twice.

Re:No comments? (0)

Anonymous Coward | about 6 years ago | (#22912546)

Highly improbable.

Squid = awesome (1)

penguinchris (1020961) | about 6 years ago | (#22908482)

What is going on? Squid are awesome and this is an interesting discovery... two comments?

Realistically I don't know if this is so "revolutionary", though - it's great for the squid, sure, but the revolutionary part will be figuring out how to actually engineer stuff like this.

It sounds simple and obvious enough, but thinking about how to create materials that behave like this one realizes the challenges involved (not that I am a materials engineer and know anything about it.)

Re:Squid = awesome (1)

Brian Gordon (987471) | about 6 years ago | (#22908738)

Darn right it sounds obvious enough, how haven't they known this before? You'd easily be able to tell by just pushing your fingernail into it at different positions down its length....

Re:Squid = awesome (1, Funny)

Anonymous Coward | about 6 years ago | (#22909102)

Darn right it sounds obvious enough, how haven't they known this before? You'd easily be able to tell by just pushing your fingernail into it at different positions down its length....

Arr, me tried that one me laddy, got me fingernail halfway down its beak before the beastie chomped off me hand and squirmed into the ocean.

Re:Squid = awesome (2, Funny)

LighterShadeOfBlack (1011407) | about 6 years ago | (#22908824)

It sounds simple and obvious enough, but thinking about how to create materials that behave like this one realizes the challenges involved (not that I am a materials engineer and know anything about it.)
Forget synthesising the process, I think we all know where this is headed: Squid farming. Why figure out how to do it when nature has provided us with the goods, handily attached to a tasty snack.

OK, so there may be a few disappointed faces when people get a prosthetic beak instead of a hand. But I'm sure they'll come around to the idea when they think about it a little bit and realise that beaks are awesome.

Re:Squid = awesome (2, Funny)

lilomar (1072448) | about 6 years ago | (#22908876)

But I'm sure they'll come around to the idea when they think about it a little bit and realise that beaks are awesome.
My only question is how far up my arm do I have to chop the hand off to qualify for this? I would like to keep my elbow, but if that is the cost of being the first human with a squid-beak hand, I can make sacrifices.

Re:Squid = awesome (1)

DavidV (167283) | about 6 years ago | (#22910344)

My only question is how far up my arm do I have to chop the hand off to qualify for this? I would like to keep my elbow,


I got what you want done, you can just get drunk and take a shortcut through a 33kV substation, not for the faint hearted though, I'd recommend against it.

Re:Squid = awesome (1)

DavidV (167283) | about 6 years ago | (#22911978)

My only question is how far up my arm do I have to chop the hand off to qualify for this? I would like to keep my elbow,


I got what you want done, you can just get drunk and take a shortcut through a 33kV substation, not for the faint hearted though, I'd recommend against it.
Damn, missed out on a Darwin Award!

Re:Squid = awesome (1)

Thing 1 (178996) | about 6 years ago | (#22919606)

But I'm sure they'll come around to the idea when they think about it a little bit and realise that beaks are awesome.

"I've got pretty nice arms, but I hate my beak."

(I love when Jonathan Coulton is topical. :)

Re:Squid = awesome (2)

UbuntuDupe (970646) | about 6 years ago | (#22908996)

Another thing that might be revolutionary about it is how it could shed light on how Spider-man's webs don't tear out chunks from his wrists because of the high, concentrated load :-/ Density gradient there too?

Re:Squid = awesome (2, Informative)

untaken_name (660789) | about 6 years ago | (#22910390)

Oh, come on. I can't even believe you're posting on such a trivial subject. I mean, really, haven't you got better things to do? Everyone knows he doesn't tear out wrist chunks because he grabs a hold of the web before swinging on it. Duh.

Re:Squid = awesome (1)

MenTaLguY (5483) | about 6 years ago | (#22925774)

Well, that and (in the comic) the web shooters are attached to a bracelet-type thingy. Assuming the bracelet were strong enough, he'd mainly have to be concerned about not tearing off his thumb at the base.

Re:Squid = awesome (3, Funny)

Naughty Bob (1004174) | about 6 years ago | (#22909294)

Realistically I don't know if this is so "revolutionary"
Are you so bold as to question the editorial integrity of /.?

No, as the headline says, the entire field of Engineering will never be the same.

Re:Squid = awesome (1)

Bombula (670389) | about 6 years ago | (#22922900)

This is indeed interesting, but I'd have to see a squid in the lab to be completely convinced there isn't a simpler explanation at work as well. The analogy of holding a razor blade with jello and using it to chop is cute, but it's only meaningful if the razor blade is sharp on both sides. Is the squid beak sharp both on the cutting edge AND where it is secured in the squid's soft tissue? Scissors (or pliers or chopsticks for that matter) don't slice open the soft pads our our fingertips not because we have bones in our hands but because - duh - scissors are only sharp on the cutting surface, and not on the surface where it is secured for leverage. And these examples only address the problem by applying direct resistance through the cutting axis of the blade. A cutting blade could also be secured with adhesion: by sticking 'tethers' to flat side. Ligaments and tendons connect hard material (bone) to soft tissue (muscle) quite well, in case you hadn't noticed.

any real advantage? (1)

dyaimz (258080) | about 6 years ago | (#22908576)

"Frank Zok, professor and associate chair of the department of materials, said he had always been skeptical of whether there is any real advantage to materials that change their properties gradually from one part to another..."
Hmmm, maybe like a sword blade FFS!

the other mystery (2, Funny)

ILuvRamen (1026668) | about 6 years ago | (#22908684)

Now if only they can figure out why the "lobster sticks to magnet!" and LOBSTER HAS A BEAK! (if you dunno what that's from, don't hate. Trust me, it's funny)

Basically it mentions a hardness gradient (3, Interesting)

Anonymous Coward | about 6 years ago | (#22908806)

Basically the article says something about a hardness gradient across the material is why the beak doesn't damage the squid itself. Then they say something about how this idea can be applied to manmade materials. Even that idea isn't entirely new anyways among manmade materials. The traditional samurai sword is forged in such a way that the edge is tempered and hardened to hold razor sharpness, yet the bulk of the blade is not hardened so that it doesn't shatter upon impact.

Re:Basically it mentions a hardness gradient (5, Informative)

I Like Pudding (323363) | about 6 years ago | (#22909192)

That's not a gradient. It's a binary transition from martensite to pearlite [wikipedia.org]. Still, I agree that the idea is not exactly earth-shattering. In fact, my kneejerk reaction was "duh".

Re:Basically it mentions a hardness gradient (5, Informative)

RockModeNick (617483) | about 6 years ago | (#22910302)

Thats the trouble with traditional Japanese differential hardening, the difference in hardnesses is slightly too great. The edges, while they hold a razor edge well when cutting softer targets, are more prone to chipping than is pleasant, and the bulk of the blade is pearlite, which while shatterproof, does not spring well enough; it's very prone to taking bends rather than snapping back into place like a spring. Don't think I'm calling the process bad or inferior, it's just different than other solutions and has its own set of problems.

Re:Basically it mentions a hardness gradient (2, Interesting)

florescent_beige (608235) | about 6 years ago | (#22920290)

I'm not really familiar with swords but I know a little bit about steel. The Wikipedia description didn't make that much sense to me possibly because it's so brief.

Martensite and pearlite aren't two mutually exclusive phases as such. Pearlite is a combination of ferrite and cementite. Ferrite is alpha-iron, a particular crystal form of pure iron, and cementite is iron carbide Fe3C. So pearlite itself is actually two phases interspersed. In plain carbon steel, pearlite forms from eutectic (.77% carbon) austenite when it is slowly cooled through the eutectoid at 727C.

Less than .77%C and you get pearlite plus a phase of extra ferrite, more than .77%C and you get pearlite and a phase of extra cementite.

This is all for steel that is slowly cooled from austenite. If quenched quickly enough, pearlite formation is suppressed (note that pearlite, being two phases, requires diffusion for the C atoms to migrate out of the ferrite phase into the cementite phase). What you get instead is martensite, which is a metastable phase where the carbon atoms remain interspersed through the iron. It is metastable because the carbons don't really want to be where they are and if they can be made to diffuse (by raising the temperature, a process called annealing) the carbons will move and pearlite will form.

If the quench is not "fast", martensite does not form fully or at all. The result might be less martensite and some pearlite or another form called bainite.

With all that, you can see why I wonder about the statement that martensite and pearlite are "binary phases". Depending on the quench rate, you can get different ratios of finely interspersed zones of the two material forms. Evidently we would like to get martensite on the cutting edge for hardness and pearlite in the middle of the blade for toughness. That means slower cooling in the middle, which I would assume means coating the center of the blade with clay to insulate it and slow the cooling rate.

What the effect of putting "clay and iron" on the blade is a bit mysterious, for the iron to have any value I would think it would have to be allowed to diffuse into the blade during the heat treat process. Also it seems that different carbon contents are used in different parts of the blade which does make sense, higher carbon content causes martensite to form more easily.

Re:Basically it mentions a hardness gradient (2, Interesting)

dbIII (701233) | about 6 years ago | (#22909792)

The sword example is really just about a mixture. You have areas of soft stuff and areas of hard stuff to get properties between the two extremes for the whole. The tricky details are you have exclusively hard stuff on the cutting edge and exclusively soft stuff on the back edge - but the majority of it is just a lot of different layers of stuff that would be too hard or too soft to be useful on their own. A modern parallel is fibreglass - hard glass mixed in with soft plastic gives you something resonably strong that doesn't shatter like glass.

Re:Basically it mentions a hardness gradient (2, Informative)

RockModeNick (617483) | about 6 years ago | (#22910242)

While forming the base steel of a sword is often done by folding overhard and oversoft steel together as you describe, differentially carburized sword blades work in a similar way to case hardened materials with a gradient of hardness as you move into the material from the outside, leaving the edges, where extra carbon seeps in from both sides, very hard, the surface of the blade very hard, but the core like a spring. This is one of the last processes that can be used before harding a sword blade, and only a blade made by a very good smith with the right type of forge can do it, but the results are amazing, giving nearly the edge hardness found in differentially hardened Japanese swords but leaving a blade with MUCH greater toughness and no tendency to chip on the cutting edge.

Not quite right - it is simpler (1)

dbIII (701233) | about 6 years ago | (#22910414)

That is something completely different. Case hardening requires a lot of diffusion which requires a lot of time at temperature and you do not want much of that in this case or you end up getting rid of the nice structures that make the thing hard while tough (springy) in the first place.

In the sword you have Wootz with a whole lot of really small hard metal carbides making it strong and you have soft Ferrite making it tough. Think of Tungsten Carbide and Silicon Carbide - the other metal carbides are almost as hard. Get it too hot for too long, the carbides break down and you lose the strength and may as well not have bothered to pattern weld in the first place.

It's really simple - layers of soft stuff and hard stuff. The layers are just very thin and there are a lot of them. It's used as an example in introductory materials science classes because it is a simple and dramatic example of a composite material and such a brilliant solution to the problem of making something out of two completly unsuitable materials.

What is describe above might be what you would use with a more conventional steel blade that has a single core material and has not been pattern welded. This is known as case hardening or carburising and in some modern material Boron is also used instead of Carbon to get increased hardness. This is done at a relatively high temperature (600C+) for many hours at a time. It gives you something stronger because the Carbon (or Boron) pushes it's way into the cubic crystal structure and forces it out of shape - to break the material you also have to fight against the extra force caused by the crystal structure being distorted. It's only on the surface because it has to diffuse through the crystal structure and that takes energy (temperature) and time. Get it too hot to try to save times and you have a completely different crystal structure and it's going to change into something else before room temperature and undo some of that hardening.

Re:Not quite right - it is simpler (1)

RockModeNick (617483) | about 6 years ago | (#22917988)

Case hardening does require high temperature, extended immersion, and anoxic heating environment, but differential carburization isn't the same thing. It can be done in an open forge with only a charcoal fire, if the smith is knowledgeable enough, and a bar of pure iron can be turned into a bar of sword hardness steel in under ONE hour if the smith knows his stuff, without burning or damaging the steel structure in any way. The hardness gradient which occurs is similar between the processes, but they are not the same process. I think you are confused in this next part... wootz is not something in a sword, it's a type of steel sometimes used for swords which has carbides segregated out of the steel matrix into visible layers, this improves cutting characteristics. Pattern welding does not create wootz, nor does it create carbide segregation, it only creates layers of different steels finely enough distributed to create something with the characteristics of homogeneous steel with the average of the hardness and other characteristics of the steels folded. Differential carburization is not an alternative process, it can be done with ANY type of sword or knife steel; simple carbon steel, high alloy steel, pattern welded steel, or wootz steel, to improve edge hardness and thus cutting characteristics without compromising toughness.

Re:Not quite right - it is simpler (1)

dbIII (701233) | about 6 years ago | (#22918338)

A couple of independant concepts are being mixed up here. I thought I stated it simply but I'll try again - you have the hard material (wootz) and the soft material (ferrite) and you bring them together and fold them over many times to make thin layers.

Now for something different. Case hardening is the most widely known form of carburization (and you can do it with a charcoal fire - in fact you can get a charcoal fire too hot for this) so that is why I used it as an example. Mixing the two methods together does not work due to the major mechanism of one - a lot of diffusion - ruining the major mechanism of the other - a lot of sub-micron metal carbides plus a lot of metal carbides in general that you don't want to lose into the ferrite that will just suck up the carbon. A lot of the strength is proportional to the number of very small metal carbides and those would join together into a softer structure if you try to diffuse a lot of carbon in from the outside. The other reason not to do it is you have a very low carbon wrought iron that will suck up a lot of carbon before you see any change in properties layered with a very high carbon material that can't really absorb any more carbon.

One of the reasons pattern welding is so hard is that it couldn't get too hot or you would ruin the structure and just get a really brittle wrought iron. One of the reasons carburization is not used everywhere is it tends to ruin other heat treatments and it is not suitable for all types of steel - very low carbon and very high carbon steels don't benefit from it and with Damascus steel you have the two extremes.

Re:Not quite right - it is simpler (1)

RockModeNick (617483) | about 6 years ago | (#22923034)

I'm pretty positive either you are mixing up how wootz is made and pattern welding, or I'm the one not being clear in what I'm talking about. I'm saying steel is not a mix of wootz and ferrite, and that you don't pattern weld with wootz and pure iron. Wootz is a type of steel with precipitated carbides, but these carbides themselves are not wootz, nor is steel without carbide precipitation wootz. Folding steel billets together creates steel with an averaged set of characteristics based on the input steels, that's all, and is different from what is done with wootz. As far as I know, there is nobody who makes actual wootz who is pattern welding it with softer materials like pure ferrite, and I keep pretty informed on modern sword making. Doing such a pattern weld would only create a weaker material, properly forged wootz already has superior characteristics to other sword steel. It does contain layers of precipitated carbides in a pattern, but this pattern is created by the smith folding or otherwise manipulating the bar of steel; it isn't two or more separate billets of steel forged together, the entire bar of steel is wootz, not just the areas with the most carbide precipitation. You don't bring together anything when making wootz, the process is actually taking a single steel and causing it to segregate into higher and lower carbide areas, more a separating than a bringing together. You start with one bar of steel, and when you are done, you have one bar of steel with layers of varying carbide density. The matrix suspending the carbides isn't pure ferrite, it's steel, capable of high hardness and resilience ferrite is not, and layers of pure iron would be undesirable to fold in. Also, if you know how to carburize steel properly it won't soften the steel, you only mess up the steel if you do something wrong, like overheat it, decarburize it(which many people do the entire time they are forging by not knowing the heating regions of a charcoal fire) or ruin the grain structure. Most smiths do all of these bad things. Folding billets of different steels together is actually only a decorative procedure in modern sword and knife making anyway, it's totally unnecessary, as there are so many choices of steels you don't have to combine others to get the characteristics you want for a blade. You can just buy steel with exactly what you want. Pattern welding is a risky process, as well, unless you are very careful when folding and of sure skill, you'll damage the strength of the steel by not getting perfect welds between the layers.

Re:Not quite right - it is simpler (1)

dbIII (701233) | about 6 years ago | (#22925900)

Wootz is used as one of the two parts for pattern welding :) It is a very high carbon steel to the point of being too brittle to be useful on it's own and contains a lot of useful impurities from it's ore. You can't make it anymore becuase the ore was mined out but similar things can be made by adding other ingredients to molten metal - something people couldn't easily do long ago - they had to use the best ore they could find instead. Pattern welding is very rarely used now because the point was to take two materials with extreme properties and get the thing with the properties you want in the end. With modern steelmaking controlling the composition in a vessel of molten metal, heat treating and forging (adds in extra strength by damaging the material the right way) give you a choice of a wide range of properites.

Now to the other half - the soft stuff used in pattern welding was known as "sponge Iron". When you don't have the equipment to melt iron ore you can heat it up as much as you can and then bash the impurities out of it. Increasing the pressure decreases the melting point. The Iron will melt at a much lower temperature than the impurities so with a lot of work you can get a very soft wrought ore that way. Not much carbon gets into Iron made this way so you have a material that is almost pure iron - it's the single phase material "ferrite". Now a modern steel is made by deliberately putting carbon in there so we can get some strength so mild steels have two phases - "ferrite" and "cementite" - however the stuff in the pattern welded swords had to be made from a really soft single phase (ie. same stuff all the way through) material. It's the same stuff that used to be used in transformer cores and AM radio antennas.

If you take a step back and look at something similar but simpler and widely used today there is another situation with steel you can look at the same way. In relatively slow cooled steels there is a layered structure called "pearlite" which gives you toughness from the almost pure iron "ferrite" phase and a lot of strength from the high carbon "cementite" phase. This is what makes a lot of very cheaply produced steels strong but also tough enough to not crack easily. That's probably a good place to look at initially on a web search (pearlite, ferrite, cementite) before looking at how things get a bit more complicated with other structures that effectively do the same thing just with better strength benefits.

Re:Not quite right - it is simpler (1)

RockModeNick (617483) | about 6 years ago | (#22926570)

We seem to be on the same page with pattern welds, but I think you misunderstand wootz. It's not overly hard, or brittle. The process for making wootz prevents cementite from forming brittle sheets by keeping it from forming a lattice; wootz on it's own is actually VERY flexible with proper heat treat. I've owned blades made from pure wootz, they aren't at all brittle. Wootz doesn't even have to be hypereutecoid, carbides can be precipitated in lower carbon steels(I believe down to about .75%, but my memory might be off on the exact number), it's just easier and requires less careful control with hypereutecoid carbon content, and hypereutecoid is more common historically than hypoeutecoid. I know one of the only people making wootz steel right now, so unless my brain is seriously jumbled I'm pretty sure I understand the material, and it isn't pattern welded. It does look like pattern welded steel, but that is because of differences in carbide density; the steel forming the matrix has been independently laboratory tested and confirmed to have a Rockwell C hardness of 56-57, no soft layers of iron, and this matches the uniform matrix hardness is historical blades, which were also folded to develop patterns, but not pattern welded. The technique was thought to be lost, but it turned out it wasn't the actual methods that were lost, but ores containing the correct alloying elements, vanadium and a few others are particularly suspect, and the actual techniques only abandoned because they no longer had the right affect on the steel. Al Pendray figured out a way to achieve carbide segregation using his own version of the ancient methods and the proper included elements, his method is closest to the historical way. A Russian fellow named Anosov is said to have found as many as 6 different methods, which he described in one sentence summaries useless to anyone trying to replicate them, and as he wasn't a fan of patents, his secrets died with him. Also in recent years, Wadsworth and Sherby as well as Daniel Watson have found ways to replicated the type of carbide segregation seen in real wootz. The ferrite/cementite structure in wootz isn't based on a pattern weld with two different structures, but on proper treatment of a single piece of steel; you can in fact heat a piece of real wootz until the pattern is actually gone, then regenerated it with thermal treatment at lower temperatures which will allow the carbides to again form around the seed elements.

Re:Not quite right - it is simpler (1)

dbIII (701233) | about 6 years ago | (#22927156)

It's so famous there's even a wiki page on wootz now which is a good starting point until I have time to find some links. What I am calling wootz is specificly the stuff from India long ago that is specificly in the pattern welded material. I really don't know what people in the the blade making community are calling wootz for marketing reasons but only from a metallurgical viewpoint. What they are calling Wootz was not in the old pattern welded blades that I am talking about. I'll see if something's on the net about it later in the day/night and put up some links. All I've got is on paper and most likely out of print since I've been out of metallurgy for eight years now.

Re:Not quite right - it is simpler (1)

RockModeNick (617483) | about 6 years ago | (#22927474)

Reading slightly out of date material would definately explain the confusion, the old blades were once thought to be pattern welded as you described, but recent research has show they are homogeneous in hardness, unlike true pattern welds, and that they are made from a single button of steel, rather than from welding different steels together. This is a fairly recent discovery, most older texts refer to pattern welded damascus and wootz damascus as the same material or indicate pattern welding as a part of the wootz-making process. When I say "wootz" I mean a steel with a matrix of a single hardness but containing layers of ultrahard carbides in visibly distinct bands, which lends a rather similar appearance. These are the critical characteristics found in all the historic blades recognized as wootz shown to have carbide segregation made in India or from ingots purchased from India; there was quite a trade in them due to the superiority of the material. The Wadsworth and Sherby process involves mechanical working of the steel in the temperature ranges during which cementite forms, oddly halfway between austinization temperature and room temperature, this mechanical working is one way to prevent the cementite formed from creating a brittle lattice in steels with VERY high carbon content. I believe this process is considered borderline as far as authenticity since it WILL work without the necessary alloying elements that allow you to recreate the carbides after dissolving them with heat, however, they will NOT return once the blade is held at a lower segregating temperature as historic wootz will. Neat to nothing is known about the lost Russian processes, because they are nearly as long gone as the historical methods from India, but it's believed some were similar in result to the Wadsworth-Sherby process, while some were nearly authentic. The Pendray process is believed to be nearly a recreation of the ancient process, and if performed with the proper alloying elements will provide results matching ancient wootz. The Watson process involves multiple thermal cycles, and also matches the ancient process in material characteristics. If these last two are considered wootz or not depends on how you define wootz. If you do so histogeographically, meaning made in the method of a certain time and in a specific place, only blades made from steel smelted using the ancient processes and now depleted ores from certain regions of India are wootz, and only modern made blades constructed from buttons of steel made back then count as far as modern blades. If you define wootz as a steel resulting from a certain process, then Pendray wootz is basically historical wootz, and counts. If you define wootz as steel that has visible carbide banding, Pendray, Watson, Wadsworth-Sherby, Russian, and historical wootz all count. If you define wootz as a material with certain physical characteristics defined by the ancient blades made in India(Uniform hardness of steel matrix, visible banding due to precipitated carbides, carbides which can be dissolved into the matrix and then re-segregated in the same pattern, lack of brittleness at very high, armor cutting hardness are the most recognized ones) then Pendray and Watson wootz will count as far as modern materials. I go by this last definition, as I generally define a raw material by its physical characteristics and to some extent the materials that go into it. I've had the luck to have the chance to play with historical wootz, have owned Watson process wootz, and have gotten to closely examine photos of both of those as well as Pendray wootz. A fun thing to do with a wootz blade is gently run the tip along a piece of glass - a standard knife will not do a thing to it, maybe chip it with enough pressure, but a wootz blade even used gently will scratch the glass with a nice, fine line from carbides much harder than the glass along the edge. At least one example of historical wootz is stainless, its a VERY unique piece, it has GOLD alloyed into the steel densely enough to prevent corrosion. The blade is a bit softer than standard because of this(though it still cuts well due to the carbides) and a bit heavier due to the weight of gold. This piece is one of the ways we are sure the historic process involved a perfectly sealed crucible(as does the Pendray process), because the much lower working temperature of gold would make it impossible to alloy with steel by any other method.

Re:Not quite right - it is simpler (1)

I Like Pudding (323363) | about 6 years ago | (#22928248)

Fantastic posts! I'd never heard of that gold alloy example before.

Re:Not quite right - it is simpler (1)

RockModeNick (617483) | about 6 years ago | (#22928428)

It's a shame it's basically totally offtopic, LOL. It's a very rare example, which very few people have seen, and easy to mistake for plated on superficial examination - however, once you see the carbide bands, it's clearly MUCH more than the simple goldplated show blade it appears to be. It makes me wonder if other strange metals could be "impossibly" alloyed under the right conditions.

Re:Not quite right - it is simpler (1)

dbIII (701233) | about 6 years ago | (#22928548)

Technically it is not an alloy but a mixture stuck together, just like fibreglass, but it really doesn't matter because you get properties of both. I worked with somebody that made an iron-pvc composite and I've made a copper-alumina (aluminium oxide ceramic) composite myself when I was still an undergradute. The secret in both cases was to mix powder of the two materials together and hit it with a very fast impact to stick the powder together. Something that is really just a big air rifle with a 1 inch bore (or imagine the chicken gun on mythbusters) did the trick to the powder in a die at the end of the barrel (dynamic powder compaction) hitting the thing at mach 1 - not hard with a long enough barrel, enough compressed nitrogen and a really good fast acting valve. The same end results can be reached with explosive welding and all kinds of unexpected things can be stuck together with actual bonding between the material. The iron-pvc material didn't have the interparticle bonding to the plastic but the iron grains welded together where they touched and enclosed the PVC which did not melt or burn.

Re:Not quite right - it is simpler (1)

dbIII (701233) | about 6 years ago | (#22928442)

I'm talking about the material as known as Wootz. You are talking about end products made from stuff that resembles wootz as a portion of their make up.

If you define wootz as steel that has visible carbide banding

No - I'm talking about the stuff from India in antiquity as per the used definition and not a the very wide range of steels that show banding. Since I brought it up in the discussion you have to live with that one and not make up a new one :) I'm beginning to regret that I named the hard material in this simple example when I was bringing up why it is not the same as case hardening. The name wootz has too much mystical bullshit surrounding it when the reality is that it was a real material used in a real and impressive process that we can't do exactly the same way because the ore is mined out.

I'm sorry: I'm not confused or out of date and was simply trying to correct a mix up above between pattern welding and carburisation. :) Also remember that there was not just a single way to make a good steel with iron age technology - if you have more suitable starting materials you do not have to use pattern welding at all to get good results.

Re:Not quite right - it is simpler (1)

RockModeNick (617483) | about 6 years ago | (#22928556)

I think we're agreed on pattern welding, I'm just not sure what you mean by wootz, do you take the historic examples only as authentic, modern materials that match in properties the ancient materials as well, or (clearly not this one from what I have read) any material with carbides which precipitate? Wootz does indeed have lots of strange bullshit surrounding it, and none of the classically recognized weapons used as historic examples were pattern welded, and I fully differential carburization is nothing necissary for making wootz, or pattern welding blades.(Although it could be done to either wootz or a pattern weld after the blade was fully formed IF you wanted and _really_ knew what you were doing so you didn't ruin the stuff.) I also agree that the historic ore is gone, but what do you think of modern wootz process that includes the critical elements through intentional alloying instead of accidental natural contamination in the source iron ore?

Re:Not quite right - it is simpler (1)

dbIII (701233) | about 6 years ago | (#22928768)

I think the things made now that call themselves that are not the same. Indian metallurgists are very proud of their Wootz and put papers out every now and again describing something that added to the strength - they've found a few different metal carbides that nobody expected that way - paticularly Vanadium, Nickel and Titanium (Titanium Carbide is the gold coloured stuff on industrial cutting tools). The really big deal about Wootz is it is such a horrible material for that purpose (it's a far too brittle white cast iron) but paired with another material it works very well. We can make far better materials today.

As for carbides coming out that happens with any steel with more than around 0.025% Carbon (varies with other elements added). The shape and size of carbides matter and if you can get stuff other than iron in there it can make a huge difference (eg. tungsten carbide, vanadium carbide etc). A lot of really small carbides shaped like needles squash everything out of shape and you have to fight the residual stress to damage the material - ie. it makes it strong. This is what you get with heat treatments like quenching or in the steel rolling mill I used to work at we just used really big fans for cooling and covers for slow cooling.

Let's just change my example to the classic Japanese sword that is still made in small numbers today by the old folding technique with a hard material and a soft material. That still answers the initial point without getting into the dozens of different things that people argue is Damascus Steel.

Re:Not quite right - it is simpler (1)

RockModeNick (617483) | about 6 years ago | (#22933186)

I think you mean titanium nitride - thats what they coat tools with. Similar composition, just nitrogen instead of carbon. Still a very hard, brittle material. And of course the good table saw blades have had tungsten carbide tips for a long time now. I understand perfectly well how composite materials work, but that isn't really how a squid beak(to stumble somehow back on topic) works; a squid beak works on a gradient from tip to base, and I had personally found the wootz discussion much more interesting than the composite materials discussion, thats why I kept going in that direction and was asking what materials you considered wootz.

Re:Basically it mentions a hardness gradient (1)

fuego451 (958976) | about 6 years ago | (#22913362)

The traditional samurai sword..

I had a different 'sword' in mind.

Understanding how to make such hardness gradients could revolutionize engineering anywhere that 'interfaces between soft and hard materials [are required].'
I've always wanted to tell a woman, "I've got twelve inches but I don't use it as a rule."?

I liked this paragraph towards the end (0)

Anonymous Coward | about 6 years ago | (#22908962)

Most people probably know squid best as fried calamari - the tasty starters popular in many restaurants. But the researchers noted that these are animals that deserve respect.

When cooked properly they do.

Evolution (1)

bendodge (998616) | about 6 years ago | (#22909086)

All this from evolution. Who would have though it was smarter than us?

I think you mean... (1, Funny)

Tenebrousedge (1226584) | about 6 years ago | (#22909158)

All this from intelligent design. Who would have thought that after the FSM took all that trouble to design an animal with all of these noodly appendages, we focus on the damn thing's beak?

Re:I think you mean... (1)

Nazlfrag (1035012) | about 6 years ago | (#22910698)

It's the beak gradient they're after, which goes from watery ramen to al dente Singaporean noodle.

Re:I think you mean... (3, Funny)

neomunk (913773) | about 6 years ago | (#22915522)

Actually, if I understand the article right, the gradient is more like soggy ramen to 3-week old dried-on-the-stove Spaghetti-o. It gets pretty hard on the far side, and cannot be destroyed without the power of Dremel at your disposal.

Re:Evolution (0)

Anonymous Coward | about 6 years ago | (#22909432)

Nature smarter than a Rondroid? ...nah, I can believe that.

Re:Evolution (1)

dunkelfalke (91624) | about 6 years ago | (#22914074)

not really smarter. nature seems pretty stupid, given how much time it needs to achieve such technical progress.

New Spam Product coming ! (0)

Anonymous Coward | about 6 years ago | (#22909708)

Harder P3nis with new Squid tech.!!

Prostheses (2, Funny)

tygerstripes (832644) | about 6 years ago | (#22910232)

One of the first applications researchers envision is prosthetic limbs.
Prosthetic beaks? Seriously?

Re:Prostheses (1)

Tablizer (95088) | about 6 years ago | (#22914236)

Prosthetic beaks? Seriously?

I needed that during the dot-com bust to fend off teens attacking my Bucket-O-Chicken mascot suit near the street corner. Had to pay the bills...
     

Wha? Let me understand this. (1, Insightful)

Anonymous Coward | about 6 years ago | (#22911614)

Using B to get from A to C is an engineering revolution?

How the hell did we ever get into space?

Re:Wha? Let me understand this. (2, Funny)

ScrewMaster (602015) | about 6 years ago | (#22912854)

Using B to get from A to C is an engineering revolution?

How the hell did we ever get into space?


I think it's because we used numbers instead of letters.

Applications (2, Insightful)

dbbd (837458) | about 6 years ago | (#22919036)

I wonder if these type of gradient based material could be used for artificial teeth. Today teeth implants are embedded into the jaw bones, but many times the bone thickness is not enough. If instead gum-hardness material could be interfacing the gum, yet be hard on the surface it could be a very good replacement for bridges.

Re:Applications (1)

Grishnakh (216268) | about 6 years ago | (#22923960)

Normal teeth work by being embedded into the jaw bones. So if jaw bones aren't thick enough for tooth implants sometimes, why not find a way to improve the jaw bone thickness so that everything works like in an unaltered human body? Gums aren't meant for enduring any pressure; they're just there to protect the tooth roots.

Heck, in an extreme case, the whole lower jaw could be replaced with an artificial one.

What about Head Crabs? (2, Interesting)

jameskojiro (705701) | about 6 years ago | (#22922334)

Does their beak work on the same principle? Does a ce-beaked squid grow it back like a missing fingernail?

General theory? (1)

Qango (1181513) | about 6 years ago | (#22929228)

This would seem to have general application. Fillings break away from teeth, taking part of the tooth with them, due to the strong bond and lack of gradation in hardness between filling and tooth. Blue LEDs were burning out at the junction until material scientists could develop a gradation of doping, spreading the load of charge across the the junction. Perhaps we could make more durable things (even abstract things) through applying a theory of gradation. I'm not an engineer though, maybe this is already common knowledge. Or maybe it's a badly investigated set of assumptions.
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