The Squid's Beak May Revolutionize Engineering

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."

Re:Basically it mentions a hardness gradient

[I Like Pudding]

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

[RockModeNick]

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.

Re:Basically it mentions a hardness gradient

[RockModeNick]

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:Squid = awesome

[untaken_name]

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.