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Scientists have found a way to harden wood to make a knife that rivals steel

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Re: Scientists have found a way to harden wood to make a knife that rivals steel

#21

Post by marcinzm »

mikro2nd wrote: post #2

Lovely idea. I would like to see a comparison of the energy requirement for hardening wood this way vs. making steel. Would give a better sense of whether this is a technology worth pursuing as one path toward decarbonising the future.

I'd like to see specific comparisons in physical properties versus steel and specifically which steel they are comparing to. Including in physical dimensions since their nail seems fairly thick. Steel is, as I understand it, hundreds of different variants each with their own physical properties.

For example, they say 23 times harder in the article than regular wood. Wood has a Brinell scale of up to 7 although most is less. Times 23 that comes out to 161. Mild steel is 120. However hardened tool steel is 900.

Re: Scientists have found a way to harden wood to make a knife that rivals steel

#22

Post by samstave »

Tistron wrote: post #7

Fun days for airport security :) How do they handle people bringing caramic knifes today? Would wooden knives display clearly on their scanners?

I think it would be interesting to use the process for the extremely high tolerance-cut-metal blocks, where the items in the block are such tight tolerances that when inserted, you cant see them.

Then - cut all the items you want into the hunk/hunks of metal such that you can pop them out in-flight and assemble your mechanisms of chaos...

You can just have non-descript blocks in a case and say they are for scientific experiments but they look like un-machined pieces in the case. heck - even have a clear lid on the case with labels of different 'alloy make-ups' to make it look more like a metallurgical kit...

Re: Scientists have found a way to harden wood to make a knife that rivals steel

#23

Post by laurent92 »

vegardx wrote: post #9
Tistron wrote: post #7

Fun days for airport security :) How do they handle people bringing caramic knifes today? Would wooden knives display clearly on their scanners?

Most ceramic knives have some metal in them for this reason.

Haven’t they moved from Xray, which shows the difference between atoms thanks to wavelength, to ultrasounds, which show sharp edges and thus is suitable for anything iron, plastic or wood as long as it’s sharp?

Re: Scientists have found a way to harden wood to make a knife that rivals steel

#24

Post by varelse »

When I was a kid I used to launch Estes rockets. They came with mostly balsa wood fins that would frequently break on landing. The balsa wood also absorbed paint unless you hit it with a clear coat first. This for some reason gave me the idea of rubbing Elmer's glue on to it, letting it dry, then sanding it and then painting it. Not only did it paint easily but I never lost a single fin again. The closest I came to that was when a fin ripped itself off the cardboard tube of the rocket rather than break.

Re: Scientists have found a way to harden wood to make a knife that rivals steel

#25

Post by generalizations »

> "Surprisingly, our wooden knife is actually three times sharper than the typical stainless steel dinner table knife," he said. "It can achieve its purpose of cutting medium well-done steak very nicely without breaking."

Cool stuff, but that's not very sharp. Still a long way to go?

Re: Scientists have found a way to harden wood to make a knife that rivals steel

#26

Post by cogman10 »

batch12 wrote: post #10
Tistron wrote: post #7

Fun days for airport security :) How do they handle people bringing caramic knifes today? Would wooden knives display clearly on their scanners?

You can already bring scissors on a plane with 4 inch blades. That's two knives.

Yeah, airport security is nothing but security theater. I wish we could eliminate it.

Re: Scientists have found a way to harden wood to make a knife that rivals steel

#27

Post by batch12 »

reayn wrote: post #16
batch12 wrote: post #10

Earlier quoted context omitted.

You can already bring scissors on a plane with 4 inch blades. That's two knives.

A scissor can't really compare to a proper forged and heat treated knife, and for the purpose of using a seemingly everyday object for a more malicious purpose there are better things imo.

Neither does a box-cutter compare to a properly forged and heat-treated knife. But for fun, forged, Damascus steel scissors are a thing.

Re: Scientists have found a way to harden wood to make a knife that rivals steel

#28

Post by ls15 »

excalibur wrote: post #11
mikro2nd wrote: post #2

Lovely idea. I would like to see a comparison of the energy requirement for hardening wood this way vs. making steel. Would give a better sense of whether this is a technology worth pursuing as one path toward decarbonising the future.

Also what chemicals are used, where do those come from, how sustainable are they, are there adverse environmental impacts in their production

Pyridine and DMSO seem to be the best solvents for lignin.

https://bioresources.cnr.ncsu.edu/resources/solubility-of-li...

DMSO is a by-product of cellulose production.

https://en.wikipedia.org/wiki/Dimethyl_sulfoxide#Synthesis_a...

Re: Scientists have found a way to harden wood to make a knife that rivals steel

#29

Post by Redoubts »

generalizations wrote: post #25

> "Surprisingly, our wooden knife is actually three times sharper than the typical stainless steel dinner table knife," he said. "It can achieve its purpose of cutting medium well-done steak very nicely without breaking." Cool stuff, but that's not very sharp. Still a long way to go?

Dunno, sounds great for everything but a kitchen knife.

Re: Scientists have found a way to harden wood to make a knife that rivals steel

#30

Post by [deleted] »

reayn wrote: post #16
batch12 wrote: post #10

Earlier quoted context omitted.

You can already bring scissors on a plane with 4 inch blades. That's two knives.

A scissor can't really compare to a proper forged and heat treated knife, and for the purpose of using a seemingly everyday object for a more malicious purpose there are better things imo.

[deleted]
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