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A Chemical Bath and a Hot-press Can Transform Wood Into a Material That is Stronger Than Steel, Researchers Find (nature.com)
The process, and others like it, could make the humble material an eco-friendly alternative to using plastics and metals in the manufacture of cars and buildings, Nature reported this week. From the report: "It's a new class of materials with great potential," says Li Teng, a mechanics specialist at the University of Maryland in College Park and a co-author of the study published on 7 February in Nature. Attempts to strengthen wood go back decades. Some efforts have focused on synthesizing new materials by extracting the nanofibres in cellulose -- the hard natural polymer in the tubular cells that funnel water through plant tissue. Li's team took a different approach: the researchers focused on modifying the porous structure of natural wood. First, they boiled different wood types, including oak, in a solution of sodium hydroxide and sodium sulfite for seven hours. That treatment left the starchy cellulose mostly intact, but created more hollow space in the wood structure by removing some of the surrounding compounds. These included lignin, a polymer that binds the cellulose. Then the team pressed the block -- like a panini sandwich -- at 100C (212F) for a day. The result: a wooden plank one-fifth the thickness, but three times the density of natural wood -- and 11.5 times stronger. Previous attempts to densify wood have improved the strength by a factor of about three to four.
There is also a summary here at Sciences News.
Ceci n'est pas une signature.
The bodies were Duroplast - a composite plastic.
Generally solid wood is a good choice for many projects due to three key reasons:
1. Cost
2. Workability; can be worked with hand tools and power tools, glues easily and strong
3. Water safe for years with no significant prep work
Steel is a lot stronger per pound, but to join it you either need to use mechanical fasteners or weld it. This requires expensive ($300+) specialized equipment like a welder and/or drill press. Wooden boats are generally good from 15-20 years without major renovations, and are serviceable with major repairs every 10-15 years up to 60-75 years after initial construction. Steel needs to be galvanized, or painted, or sanded and resurfaced every 2-5 years, especially in a saltwater environment (most of the things in your house arrived from asia in a big steel boat).
Super dense wood that's lost most of it's lignin likely is hyper brittle and doesn't machine well. Also, I can only imagine what happens when it's immersed in water. There's a non-zero chance it swells up like a dry sponge when it comes in contact with water or even regular humidity.
moox. for a new generation.
TFS says:
> Attempts to strengthen wood go back decades.
Decades? Really? People have been firing wood and embedding carbon into its surfaces for at least 400,000 years. This author is off by at least four orders of magnitude.
Whats the energy cost vs other materials ?
Waste treatment ?, what are the by products, how do we dispose of them properly ?
Recycling of the finished product ?
Long term stability over time at different temperatures
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#DeleteChrome
You just invented plywood!
Plywood is weaker than normal wood not stronger and definitely not stronger than steel.
Not when sandwiched vertically in a weight-bearing truss.
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Ernest Hemingway
just recycling an infinitely renewable inorganic compound or metal?
I never followed that "logic".
Trees grow ridiculously slowly. And no, you can't just plant a few fast-growers (in a mono-culture even) and call it the same as an ancient complex forest eco system that sustained tens of thousands of species in an elegant balance of cycles!
Meanwhile, metals and generally crystals and materials made from ore are easily recycled in a single day, with some smelting and forging, using only solar energy from places where nothing lives anyway.
"Stronger than steel" is silly anyway. Steel is not very strong. And what do you mean with that word anyway? There's half dozen things that that can mean, and in none is steel quite the best we have. Steel is only popular, because it is very abundant and very cheap, with acceptable properties.
Using trees for building things (apart from decorative furniture and the likes) is as stupid as using fields to grow crops to then turn them into gasoline instead of food.
Then the team pressed the block -- like a panini sandwich -- at 100C
People who read news for nerds might not be able understand what pressing a block means in this context. A highly accurate and technical description, make it so readily comprehensible. Like a panini sandwich! Good, someone might mistake pressed the block something like a burger or a calzone. One might even be thinking of pasta or pilaf or masala dosa. Now it is clear. Press the block like a panini sandwich. Good. Great job.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Trabants were partially made of plywood, weren't they?
Yes. Also, many WW2-era German, Russian, and British aircraft of many types including fighters, especially early in the war for the Soviets and late in the war for the Germans, used various types of laminated and/or compressed wood, some as a major percentage of the vehicle. The British Mosquito was one of the fastest aircraft in the WW2 sky and made the first bombing runs on Berlin due to it's speed, payload capacity, long range, and was made largely from wood. It served many different roles from heavy fighter, to twin-engine fast bomber, to fast reconnaissance, and more. Pilots loved the "Mossy". It was such a great aircraft the Germans tried to copy it, but with only limited success.
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
Even more stupid, at least in the short term, but in the long term, this might actually make sense (whereas ethanol as a fuel will never make sense).
Imagine this world a few thousand years from now. We've run out of metals suitable for building things, because they're all in use for something. If you want to build a new building, you have to tear one down first, because there's no steel left to make the girders. Mining asteroids to get more iron is, of course, an option, albeit an expensive one. But for a cheaper alternative, we could plant fast-growing trees and make up for the lower density of the soft wood by using a process like this to turn it into something stronger.
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In WW2 the British built a multi-role military aircraft called the "Mosquito" out of plywood. Originally conceived as a very fast lightweight bomber, it was a brilliant success at a wide variety of tasks: night fighter, high altitude interceptor, ground attack craft, photo-reconnaissance craft, torpedo bomber.
Basically it was the anti-F35: designed to do one thing well, it ended up doing everything pretty well.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
The chassis of Morgan sports cars (just about all that remains of the UK owned car industry) are still made of ash.
Because if your metal goes in the trash, it doesn't come back.
Can you explain this? It's not like you click on "empty trashcan" and the metal is deleted. That trash is taken somewhere and emptied into something. It doesn't vanish. It can come back.
Note that "strength" in this context is per cross sectional area. So taking a block of wood, and compressing it down doesn't change its absolute strength (it can support the same weight as before), but increases its measured strength (load per square mm of cross sectional area before failure). One of the attractions of metals like steel is their isotropic properties - they have the same properties regardless of which direction you load them. Fibrous materials are anisotropic - stronger in certain directions than others.
Glass fibers are also stronger than steel in tension, but they're weaker in compression and absolutely suck in shear (loading perpendicular to the fibers). The fibers just bend sideways instead of offering any resistance. So we embed them in a matrix of plastic (polyester or epoxy) to create fiberglass. Tensile and compressive strength are reduced, but shear strength improves substantially - enough to where you can walk on a fiberglass board whereas raw glass fibers would simply flop over and let you fall through. Where a fiber used to bend, the plastic matrix absorbs and transmits those forces to other fibers, converting shear forces into tension and compression (the board bows downward in the middle, compressing in the top half, stretching in the bottom half).
It sounds like what this team has done is taken wood, and cooked it so the cellulose fibers remain but much of the matrix which holds them together has been removed. That has little consequence in tension, but could weaken shear strength to where the material is structurally useless except as rope/cable.
Near as I can tell, the word sturdy, in the hands of furniture marketers, has become the exact opposite of what we normally take it to mean. Any piece of furntiure described as "sturdy" is almost certainly the flimsiest thing you'll ever find. Unless of course the description also includes the phrase "wood product"
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You're right in that wood does not bend and collapse the way steel does. But what it does do is **feed the fire**. Even wood treated to be less flammable still burns more easily than steel does. (and gives off toxic smoke once the fire overwhelms the chemical resistance. When the wood studs and joists in a home are burned to more than something like 15% of their cross section, they can no longer be expected to carry the load. Wood framed structures collapse more readily than the equivalently steel framed structure. (Note: I am not referring to the thin steel wall studs used to build partition walls, those are never intended to carry any load beyond the weight of the drywall mounted on it. Even a small twist caused by the collapse of an adjoining area totally destroys any load bearing capacity the studs have)
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In some places landfill mining is already being done, but with an eye to reducing the volume of existing waste so that new waste can be added. (Planners have a hell of time finding good sites for a landfill even before the NIMBY crowd get involved.
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Oh, it gets much better than that. From Wikipedia:
Similar to fiberglass, Duroplast has limited possibilities for efficient disposal. As discarded Trabants began to fill junkyards, disposing of the bodies inspired creative solutions. One of these was developed by a Berlin biotechnology company, who experimented with a bacterium that would consume the body in 20 days.[2][3] Urban legends, depicted in the movie Black Cat White Cat and described in a song by the Serbian band Atheist Rap, described recycling Duroplast by
feeding the cars to pigs, sheep and other farm animals.
Duroplast flavored bacon? Yum, yum!
After the Berlin Wall fell, Germans voted with their wallets on how they felt about Duraplast cars. Although, the Trabi was overall a crappy car, so it wasn't just the Duroplast. It's amusing that just across the border, the West Germans were building BMWs and Porsches.
That shows you how bad communism is. Under communism, you can take take a nation of Germans, and only make crappy cars with them.
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
Yes and no. The 2x4s used in standard residential framing burn quite readily. Larger timbers form a protective char, which, as long as it remains on the wood, protects the inner core from fire. If the timber has been specced correctly, the char does not penetrate deeply enough to compromise the structure for some time.
Steel, meanwhile, is an excellent heat conductor and therefore will start to sag as soon as the outer edge of the steel has reached a temperature that will cause sag.
Looks like the chassis is metal but the frame is ash:
https://www.classicdriver.com/...
Good luck digging that deeply, unless you remove the moon, move our entire planet away from the sun a few AUs, and wait billions of years for the radioactive material inside to fully decay so that the core won't be so hot. :-)
If you assume that materials are distributed evenly, then you're right that we won't every truly run out, but that isn't a realistic model. Ores come in veins, separated by miles and miles of crap. At some point, we will exhaust the veins near the surface, and then the cost of mining will go up considerably. For iron, that might never happen, because it is really, really common, but for other components of steel (e.g. chromium, which makes up 16% to 26% of stainless steel by volume), it seems a lot more plausible. Whether that will happen in a thousand years or ten thousand, I couldn't begin to guess; that was an entirely arbitrary number. The point is that eventually, some important raw materials used in making construction materials will be deep enough that other alternatives will start to make sense.
Check out my sci-fi/humor trilogy at PatriotsBooks.
Actually, it was Duroplast mixed with wood chavings to save on the expensive plastics and still being able to freely form it. The duroplast effectively worked as a malleable glue to keep the wood chavings together. (And yes, my father owned a Trabant.)
An indication of just how good the Mosquito performed is the grudging admiration of Hermann Göring:
In 1940 I could at least fly as far as Glasgow in most of my aircraft, but not now! It makes me furious when I see the Mosquito. I turn green and yellow with envy. The British, who can afford aluminium better than we can, knock together a beautiful wooden aircraft that every piano factory over there is building, and they give it a speed which they have now increased yet again. What do you make of that? There is nothing the British do not have. They have the geniuses and we have the nincompoops. After the war is over I'm going to buy a British radio set – then at least I'll own something that has always worked.
That is incorrect.
Everyone used wood, as it is leighter, hence the planes climb faster and use less fuel.
Technology to make robust steel planes did not even exist at that time. Aluminium even less so.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
After the war is over I'm going to buy a British radio set â" then at least I'll own something that has always worked.
And speaking of British radio sets, Mullard, a now-defunct British maker of vacuum tubes, were and still are a world standard for vacuum tubes. Old-stock "new" original Mullards go for ridiculous prices these days among audiophiles and electric guitarists and are quickly scooped up, when they can be found at all.
There are current-production tubes labeled "Mullard" but the rights to the brand name were acquired by a Russian company called Sovtek who market tubes under several brand names, including other now-defunct makers like Tung Sol as well as the Mullard badge. None of them are equals to the originals, often markedly different in how they perform and sound from the originals.
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
So in modern marketing terminology, it was an advanced biopolymer composite. ;)
Ezekiel 23:20
Dear Click and Clack, My car has termites - please help!
Dear reader,
Pest problems with your Morgan can be addressed by any competent fumigator.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
A Chemical Bath and a Hot-press Can Transform Wood Into a Material That is Stronger Than Steel, Researchers Find
Why pay $15 a pill when you can just immerse in a bath of our special salts?
Warning: If you experience "steel" for longer than a few hot presses, contact your chemist immediately.
Wood will be impregnated, but does not prevent pregnancy.
May cause blue vision.
just recycling an infinitely renewable inorganic compound or metal?
I never followed that "logic".
Trees grow ridiculously slowly. And no, you can't just plant a few fast-growers (in a mono-culture even) and call it the same as an ancient complex forest eco system that sustained tens of thousands of species in an elegant balance of cycles!
Carbon also gets locked up in trees... whilst trees grow, that's carbon out of the atmosphere. Where wood is used to build houses (that's carbon out of the atmosphere)... Yes, obviously it takes burning fuel to build those houses and prep that wood... but it takes even more with steel.
Trees may grow slowly, but that's all for the best- they provide a habitant for wildlife whilst they grow (regrettably mono-culture isn't the best for wildlife), This also means you need more hectares to get enough for building. Here in the US, we stupidly subsidize maize (but not other fruits and veg to the same extent)- even though maize is one of the least healthy foods you can get and adds to the obesity epidemic. (we're using tax money subsidies to make ourselves fat).... but that's a topic for another day.
Wouldn't it be better if instead of so many fields filled with maize we had trees growing on a lot of it instead? Prettier, more environmentally conscious (at least in areas that would naturally be woodlands)- the dry parts of the Midwest can still grow maize for all I care.
"That's the way to do it" - Punch
The Germans make average to decent cars. Where they excel is in the marketing and advertising.
Throughout most of automotive history and up into the early sixties, America made the best vehicles and did the most to push automotive technology, not that it was that much.
In the late sixties and seventies, nobody except maybe the Swedes could touch the Germans on any level. Not in build quality, not in performance, not in interior quality, period. It was Europe's time to shine. Parts of it, anyway.
From the eighties through the mid to late nineties, nobody could even begin to compete with the Japanese. Systems design, build quality, reliability, performance per dollar spent, you just could not even screw with the Japanese.
Today, everyone can design and build a car except maybe the Chinese — they can definitely build them, but they haven't been building them long enough to know if they can really design them. Most indications suggest that they are just getting the hang of it, though. The point is, there's nobody who really stands out as being drastically more competent than anyone else any more. There's only some companies which you notice for being less so, which sadly includes Chrysler Corp which used to dominate the advancement of new automotive technology.
Up until the mid-eighties, the Germans still "over"-engineered cars. They wanted them to exceed expectations whenever possible, and they still cared very much about maintainability. Today, German cars are designed like every other vehicle — packaging considerations come first, and they are a beast to maintain. You need all manner of special tools to do even simple things, and they're mostly not tools that are easy to make, either. Even their fleet vehicles are like that. I had to make a special tool just to press the ball joints out of the A-arms on a 2006 Sprinter. (Or I could have bought a toolkit that costs minimum $140...) My 1998 Audi A8 is a PITA to work on every time. But my 1982 300SD (FSBO) has lots of room to get hands into, electrical connectors that you can snap open by hand and pins that are soldered to wires and easily and cheaply replaceable, and will keep going down the road and get one to work if the electrical system dies completely.
TL;DR: It's not a myth that German cars were superior to everything else once.
P.S. Last I heard, Audi was #2 in reliability, behind Lexus
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
However, nobody was really concerned about how hard they would be to sink, because there was no way to keep the Germans from sinking them if they found them
Actually the 'unsinkable' nature of pykrete ships was a selling point
https://en.wikipedia.org/wiki/...
When I had read their report, I advised my superiors to scrap our experiments with pure ice and set up a laboratory for the manufacture and testing of reinforced ice. Combined Operations requisitioned a large meat store five floors underground beneath Smithfield Market, which lies within sight of St. Paul's Cathedral, and ordered some electrically heated suits, of the type issued to airmen, to keep us warm at less than 0 degree C (32 degree F) temperatures. They detailed some young commandos to work as my technicians, and I invited Kenneth Pascoe, who was then a physics student and later became a lecturer in engineering at Cambridge, to come and help me. We built a big wind tunnel to freeze the mush of wet wood pulp, and sawed the reinforced ice into blocks. Our tests soon confirmed Mark and Hohenstein's results. Blocks of ice containing as little as four percent wood pulp were weight for weight as strong as concrete; in honor of the originator of the project, we called this reinforced ice "pykrete". When we fired a rifle bullet into an upright block of pure ice two feet square and one foot thick, the block shattered; in pykrete the bullet made a little crater and was embedded without doing any damage. My stock rose, but no one would tell me what pykrete was needed for, except that it was for Project Habakkuk.
* I Wish I'd Made You Angry Earlier, Perutz, Max
A good deal of consideration, much of it highly technical, was also given to the feasibility of building floating platforms which could either be used by fighters to support opposed landings until such time as airfields ashore were available, or act as staging points for ferrying aircraft over long distances. The idea as originally conceived by a member of Combined Operations staff, and vehemently supported by Mountbatten, was that these floating platforms should be constructed out of icebergs. They would be provided with engines which would enable them to steam at slow speed, and with refrigeration plants to prevent them melting. They would be unsinkable. The whole thing seemed completely fantastic, but the idea was not abandoned without a great deal of investigation. Various alternative methods of construction were then considered by the United States naval authorities, but in the end there was general agreement that carriers and auxiliary carriers would serve the same purpose more effectively."
* The Memoirs of Lord Ismay, Ismay, General Lord
The other intriguing property was that they could be made so large that conventional bombers could land, refuel and take off from them. Even now aircraft carriers have very strict limits on what aircraft they can support - the planes need to be navalised so they can survive short takes offs and landings. The selling point of an Pykrete ship was that you could land a heavy bomber, refuel it and have it take off again. You could have a few in the Atlantic and have bombers take off from the US, refuel on a Pykrete base mid Atlantic and arrive in the Europe or vice versa. Anti submarine aircraft could refuel on them and protect convoys from U boats. Fighters could refuel on them and protect them from bombers.
They're not so much carriers as floating islands. If bombed they could be repaired with seawater. However the side that had them would end up having air superiority over the whole Atlantic, so in the long run the Germans wouldn't have been able to get close enough to bomb them.
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
Well what do you expect, real wood is expensive to make, it's not like real that stuff just grows on trees.
If I had a DeLorean... I would probably only drive it from time to time.
They made those planes out of wood because they didn't have enough metal.
Lack of aluminum was an issue but the reason the all wood Mosquito was economical was that Britain had a lot of underutilized wood craftsmen during the war. Building the Mosquito would impact neither the existing workforce working with aluminum or require aluminum. Without all of the underemployed furniture makers and musical instrument makers, it would not have been economical.