InventWood is about to mass-produce wood that's stronger than steel
techcrunch.com
techcrunch.com
And there are only smaller comparisons towards steel. They are more focused on how it compares to regular wood.
In summary, what they are doing: 1. Boil the wood. 2. Press the wood. 3. Done.
"First, natural wood blocks were immersed in a boiling aqueous solution of mixed 2.5 M NaOH and 0.4 M Na2SO3 for 7 h, followed by immersion in boiling deionized water several times to remove the chemicals. Next, the wood blocks were pressed at 100 °C under a pressure of about 5 MPa for about 1 day to obtain the densified wood"
Pretty simple and straightforward.
This process will need to regenerate almost all of that sodium hydroxide and sodium sulfite, or it's just peracetic paper again.
I have high hopes for this product as a leg of sustainability.
Here's a NileRed video replicating the process.
Now, Ipe is very expensive. I would hope this is less expensive than Ipe, and then the trick is to make your starting materials much larger, and being able to account for the shrinkage once the densification process has been completed.
You could also do laminates of this densified wood, in order to be able to use it for beams, plywood type functions, etc…. Or even fire resistant 2x4 boards.
In seriousness, nominal vs actual sizing is just terrible. Do places outside of North America do this too?
https://www.inchcalculator.com/actual-size-of-dimensional-lu...
That's just an old wives tale.
Lumber shrinks for money reasons, older lumber is bigger [1] with sequential revisions to the standard decreasing it's real size [2] [3] (the difference between 2in and 15/8in in strength is minimal however you can keep doing that math, and they did, to go down from 2in to 1.5in over a century).
[1]: https://www.reddit.com/r/mildlyinteresting/comments/vv9atu/t...
[2]: https://ntrl.ntis.gov/NTRL/dashboard/searchResults/titleDeta...
I understand the origins of this. But I've never understood why we haven't moved on to actual sizing given the scale at which standardized lumber dimensions are produced
I wonder how it impacts the effects of humidity and time to make wood warp.
A similar phenomenon occurs sometimes in papers about ceramics research. A very tough ceramic will often see a comparison of its fracture toughness to that of aluminium; as you've guessed, this usually refers to the toughness of pure unalloyed aluminium.
You could build your floor joists out of scaffolding boards, but they'd bend unacceptably.
Stiffness is basically a product of geometry rather than strength. Making your wood stronger doesn't help you if you need it to be stiffer.
The strength is 483–587 MPa, I seem to see when skimming, which is indeed superior to ASTM A36 structural steel (250MPa yield strength). In Extended Data Figure 1c, they reported the density as 1.3g/cc, a sixth of the density of steel. (Extended data figure 2f plots density against lignin removal percentage.) Of course high-strength steels are stronger, but not six times stronger.
As for the process, they didn't just boil the wood; they boiled it with lye (2.5M, the "food industry chemical") and sodium sulfite (0.4M, technically also a food industry chemical, used for example as an antioxidant in wine) for 7 hours before densifying it with 5MPa for "about a day", removing optimally 45% of the lignin. This is similar to the sulfite chemical wood pulping process that preceded the Kraft paper process, just carried out at high pH and not taken to completion, so in a sense I guess the result is sort of like Masonite, which is also made from cellulose fibers from wood bonded with the wood's natural lignin.
Environmental concerns may be an obstacle; sulfite pulping is nasty. Also presumably to mass-produce the stuff they'll want to find ways to shorten the cycle time, and maybe already have.
The burning question that arises in my mind is why nobody was doing this in 01890, 135 years ago. Sulfite pulping was going gangbusters, building materials were booming, environmental concerns were largely unknown, and there was a rage for everything newfangled, modern, and "scientific". The scientific discipline of strength of materials, needed to calculate the benefits, was already well developed. Mason put Masonite into mass production in 01929, with a process involving autoclaving wood chips at 2800kPa. So what prevented someone from selling Superwood back then? Did nobody try partial alkaline sulfite pulping and pressing the result?
> The burning question that arises in my mind is why nobody was doing this in 01890, 135 years ago
> Mason put Masonite into mass production in 01929
People have been doing that since at least 01998.
https://web.archive.org/web/19991128020723/http://longnow.or...
> established in 1996 ... The Long Now Foundation hopes to "creatively foster responsibility" in the framework of the next 10,000 years. In a manner somewhat similar to the Holocene calendar, the foundation uses 5-digit dates to address the Year 10,000 problem[2] (e.g., by writing the current year "02025" rather than "2025"). The organization's logo is X, a capital X with an overline, a representation of 10,000 in Roman numerals.
---
They zero pad, but it doesn't seem like anyone else does so with the https://en.wikipedia.org/wiki/Holocene_calendar
My daughter recently started researching extracting/converting CNCs from fabric blends (currently cotton/elastane like spandex). Reading this post made me wonder if we can then remake fabric from CNCs, strong against knives or bullets?
This all sounds very interesting if you have any links!
Many of the slides aren't available yet, but I'll try to curate some from photos. I'll put photo number from Dropbox, since they make direct-linking hard.
Photo 62 to 67 shows the H2O2 work from Mark Andrews' lab at McGill, being commercialized by a company called Anomera.
Photo 8 and 9 has a Cyrene whitepaper from Merck/Sigma-Aldrich. They did have presentations about it, but I don't have notes, will try to get from my daughter as she wants to try it for her process.
Photo 16 has a revisualized Periodic table of elements, logarithmically scaled by availability and color-coded with scarcity / conflict / need. We only have 100 years of Indium left and that was sorta worthless >20 years ago and now used in every touchscreen. had photo but put source link instead [4]
Photo 2 shows that we are now man-making stuff at a greater rate than the earth is creating stuff and that is rapidly increasing. The point there was that we will keep doing this, so we need to make it sustainable and circular. Photo 5 shows how FUBAR'd we are.
Happy to try to answer other questions, but noting I'm not a chemist but a chaperone, so I'll have to ask other people.
[1] https://www.isgc-symposium.com
[2] https://news.ycombinator.com/item?id=43974375
[3] https://www.dropbox.com/scl/fo/5u8xmvcxv5x1zyzaq0jxu/APJPtEo...
Maybe because at that time tropical hardwood was readily available at low cost?
I suspect that the problem us, as usual, in the price. Also possibly with the high anisotropy of the material
So it's entirely possible that the process was found, and discarded straight away because they didn't realize how cool their invention was.
blushes
curious: What's with the funky date notation? Is this the new cool thing?
Call me skeptical, but reformatting dates for a "bug" in 8000 years seems extraordinarily silly. To think humanity will likely be using the same time measurement systems, computers that operate remotely similarly to ours today, same written/spoken languages, etc is laughable. 8000 years ago, the entire world's human population was roughly equal to that of London today and still just figuring out agriculture.
We still write year 476 as 476. We don't have to write 0476 to prevent confusing it with 1476. It's not confusing.
The posted Techcrunch article directly links to the Nature paper, it is the very first link of the article
As for the reason it wasn't my wild guess would be that they were already mining for coal so it may have been more economical to just dig the ground with quasi-slaves rather than having more competition on the wood resource and waiting for it to boil whereas you can just produce steel bar by the kilometer in a factory.
I think that your critique of Gilded Age exploitative labor practices is not to the point.
Yes, lignin puffs up the wood, when some of it is removed by boiling and then heated up and pressed at the same time, carbon molecules bond with each other exponentially more.
I was researching this subject two - three years back. Anything that needs to be able to move at some point, benefits a lot by being 6 times lighter. Also buildings are always constrained by their weight when trying to make them as tall as possible.
I'd argue that it is to the point insofar as the price of labor is important to the competitiveness of a finished product, isn't it so ?
I think your response stems from the fear of me trying to turn this into something "political" but it seems to me that going down the mine has been really hard work and low pay for most of History. I am pretty sure that most historians would agree that mining is one of the easiest use of slave labor (go down the mine and bring back the stuff failing which you will be punished, also no skills required) from the point of view of slave owner/manager that is. I am also sure they would agree that after the abolition of slavery, you could consider a big chunk of mine workers, quasi slaves. Hell, even today, mining is one of the main use for drug-addicted labor force in Myanmar and child labor in Congo.
Correct me if I'm wrong, but almost all use cases for wood rely on it to be somewhat light, for which the lattice structure is already fairly ideal.
The sawdust planks wouldn't have the properties of the long-grain wood fiber planks though. The fibers that make up natural wood are what makes the wood tough.
Plywood can be nice. It doesn't expand with temperature changes like planks and doesn't have a grain direction that it can split along.
The others, I hate. Any small amount of moisture and they delaminate. OSB is so ugly and rough that you need to hide it because you'll never be able to apply enough primer to cover the chip pattern. I'd rather just use regular plywood at that point. Particle board is the same, but I'm okay with the kind coated on both sides with melamine. It's pretty hard to get a much flatter surface than melamine particle board without spending ridiculously more on granite.
But MDF is the worst. A lot of people like MDF because it's easy to work and can be fairly structural, if you use it right. But it's very, very easy to damage, has absolutely zero edge strength, and it makes a super-fine, extremely carcinogenic sawdust that is extremely difficult to clean up completely. Yes, all sawdust is carcinogenic, always wear a mask in the wood shop, but MDF sawdust never goes away.
Frankly, it's just easier to get a bunch of sheets of birch plywood and southern pine dimensional lumber shipped direct to my house and not worry about it.
You are evidently thinking of chipboard, not plywood.
Chipboard (also known as Particle Board), is a wood composite material of wood chips and sawdust, compacted and bound together with adhesives.
Plywood is made of multiple cross-layered wood veneers, pressed with adhesives.
A bit more detail at [0].
Thank you - yes, I mixed them up in my head!
Show the [beep]ing picture!
Plus, all the text on the page is future tense, talking about what the super wood beams will be able to do.
So I don't know how much that picture really represents what the wood will look like.
The picture at https://www.inventwood.com/superwood-facade also looks AI-generated.
The fact that they're using AI images on their landing pages does not give me confidence in the quality of the product.
https://www.inventwood.com/technology
But I’m not sure if it a real photo or some sort of… analogy? Under “INTRODUCING SUPERWOOD: THE NEXT GENERATION OF BUILDING MATERIALS,” we can see one piece that looks like an actual piece of wood, and then some other ones that looks like an artificial wood-looking finish wrapped around some core which visually looks metallic (but which, I assume, is actually their engineered wood).
I dunno. I guess “being wood” is more about the ecological impact in this case. If it is replacing steel and it looks ugly, well, a lot of steel looks ugly and then gets covered up.
They didn't even bother to AI-upscale it to get rid of the artifacts
Then, even worse, they RELY ENTIRELY ON UNLABELED AI GENERATED IMAGES.
I cannot imagine a better way to say "there's a high chance everything we've promised is fake news". Just make sure to squint before looking at our ad copy!
U. of Maryland announced this specific process back in 2018.[2] They got a paper into Nature.[3]
Densified wood is over a century old. [4] You can buy something called "Lignostone".[5] But that is a material where they took the lignin out and put some plastic in. (Remember "transparent wood" from a few years ago. Same concept, with a transparent plastic.) This new process takes the lignin out and compresses the cell structure.
If you could send in $20 and get a little cube of the stuff to look at and test, this would be more convincing.
[1] https://www.youtube.com/watch?v=JiHABi97rU8
[2] https://www.thechemicalengineer.com/news/new-densified-wood-...
[3] https://www.nature.com/articles/nature25476
[4] https://jwoodscience.springeropen.com/articles/10.1186/s1008...
Here's someone from the InventWood team talking about the product, uses, future, and more at a trade show.
They show a hands-on demo of the wood product and give an animation of the process.
The talk is pretty illuminating. They think this will even be used in the automotive sector in places where carbon fiber is currently utilized.
This is way better than the press coverage and actual website.
However, I lost all hope (of the little I had) after their sales rep said they "densify" their wood. My dude, if you need to spin so hard you pull out a thesaurus for "compress" it's not a great look.
fwiw, I first thought this was going to be some innovation in glue, which allows manufacturers to turn wood chips and sawdust into MDF, OSB, and particle board. These are typically weaker than sawyered beams of the same size because the glue is not as strong as the cellulose fibers that run the length of a beam. (However, they are getting applied more and more in the construction in the US because it is crazy expensive to find a tree that can produce thick enough 40 ft beams, but you can easily get enough sawdust to make an even thicker, precut MDF board.) But I thought no shot, because if you can make glue that is stronger than cellulose, then why bother with the wood?
https://www.fpl.fs.usda.gov/documnts/pdf2018/fpl_2018_song00...
https://techcrunch.com/wp-content/uploads/2025/05/SUPERWOOD-...
Laminated timber is also very construction-friendly. It can be worked with simple tools, and CNC machines allow for prefab components to be shipped to the site and assembled quickly with minimal fuss.
There are some plans for high rise construction with this material. E.g. there is a plan for a skyscraper in Tokyo (350 meters, 70 floors).
The adhesives used in laminated timber aren’t perfect. They’re very durable, which is great for structural integrity. But it also means the material breaks down more slowly in a landfill (if you decide not to recycle the material for some reason). However, newer adhesives used for this these days are less toxic and not that harmful in a landfill. And importantly, most of the material is actually just wood, not glue.
Is it possible to make smaller scale CLT, with thinner boards or something, and build like cars or airplanes out of it?
That said, CLT has 2 major advantages over regular wood:
1. It is more dimensionally stable, it expands/contracts less and in a more uniform way.
2. It is cheaper at larger dimensions. I.e. 0.5m x 0.5m x 20m wooden beams would take decades to grow and even then not realiably, but you can just manufacture CLT beams with those dimensions easily out of <10yr old trees.
Those two advantages are not limiting factors for the construction of cars or airplanes, so CLT is not super relevant to them.
A lot of modern cars are made with a lot of composite materials that probably have better properties. But I imagine CLT could work well for things that are currently made out of steel or aluminium on such cars. I'm not sure if there's a big advantage to doing that in terms of strength, weight, or durability though. Aluminium might be lighter. And composite materials provide better strength and weight.
I don't know what the implications are for recyclability, but there's no mention of injecting other materials so perhaps it decomposes in a similar way to ordinary wood?
I'm no expert on this subject by any means, but I happen to volunteer at a museum where we have steam trains running. We build our tracks to look traditional, so we use wooden sleepers and no ballast. Most of our sleepers are donated from the commercial railroad companies, typically they are old stock but we also receive used ones occasionally. In my part of the world wooden sleepers aren't common anymore, so it's getting harder to find usable ones. This is a concern for us, as apaearantly there aren't any suppliers left in our part of the world for new ones. At our museum they typically last for about 15 years, mainly because we place our sleepers directly on the soil (no balast). The tar/oils will eventually dry out and the wood will just rot/decompose naturally. Wooden sleepers are considered chemical waste in my part of the world, though I do believe we are allowed to let them decompose fully as biomatter, which goes quite quick if in contact with moist soil. Though we typically dispose our used sleepers at a specialized waste facility, I'm not sure how they process it there.
Oh, and in case you are wondering: no, they don't burn, so we can't use them as firewoord for our steam engines ;-)
Appearantly in the USA, at least as of 2008, around 90% of all track was still using wood [1]. I didn't expect that. For most of the world we have used concrete sleepers for a long time already. Plastic sleepers are also common nowadays, which are typically made from recycled materials.
[0] https://en.wikipedia.org/wiki/Creosote [1] https://en.wikipedia.org/wiki/Railroad_tie
This is for a few reasons, but the two primary ones are that wood is very cheap and plentiful in the US compared to most of the rest of the world, and we haven't banned creosote in the US like most of the rest of the world, so creosote treated wood is still the most common type of railroad tie.
Like everything else there's probably some 2nd/3rd order consequence of regulatory perversion that prevents it. Like because of the circumstances it wrongly gets classified as hazmat or something.
IIUC, they replace them with plastics since the plastic is seemingly more ecologically friendly and easier to recycle.
Mind concrete sleepers are what's used these days. You'll find wood only in shunting or cargo yards. (Or museums. Or the US - see linked commen by LeonM).
Source: I randomly met someone involved with that project. A proper train enthusiast can probably elaborate here, but I think I remember the core idea correctly. Also this obviously doesn't necessarily hold globally, though I can imagine many track operators face similar challenges.
Edit: While I wrote the above, LeonM wrote a nice reply on a sibling comment - https://news.ycombinator.com/item?id=44028161
And steel is 100% recyclable, indefinitely.
Hard to beat.
but steel doesn’t store carbon (except the small carbon input used to turn iron to steel)
wood, on the other hand, is a carbon sink.
> Hard to beat.
Since wood is actually carbon negative, it still manages to beat steel.
Compress the wood and then inject it with resin to stabilize it. Effectively it's only very partially wood and more resin at the end.
After double checking, the video references the science paper from the article, so yes, it's 100% the same process.
given the depth the of the penetration, he basically case hardened it. you can see in the bullet tests that the interior laminations are much fatter than the exterior layers.
Other than that, I'm all for it. We're renovating our house currently and made some structural changes. Would've loved to exchange some load-bearing steel beams with wooden ones so we could even leave them exposed as a design element.
Compressive strength
Tensile strength
Shear strength
Flexural strength
Torsional strength
Impact strength
Fatigue strength
Hardness
They claim the fire properties are good, but I don't know enough about fire to know if they tested all the important properties.
https://www.cbsnews.com/boston/news/i-team-lightweight-beams...
They are very commonly used in new house construction past a certain year for the central support beam, or the side beams, or both - that virtually everything rests on.
In a house fire, the beam heats up, the binder/glue weakens, and the beam suddenly fails - causing the interior of the house to collapse partially or entirely which not only sends the firefighters into the basement and possibly under a pile of debris, but it breaks up a bunch of housing materials that are suddenly exposed to the fire..
Done solely to make the profit margin for the contractor slightly bigger...
If you have such beams, it's probably worth looking into how to add insulation to extend the time before the beam fails.
> The result is a material that has 50% more tensile strength than steel with a strength-to-weight ratio that’s 10 times better
This is (imho) impressive, and much better than untreated wood, but I think it's misleading to say "stronger than steel" when that labels a huge range of materials.
The biggest issue actually is that there's a lot of resistance in the construction industry that is simply locked into using steel and concrete and more or less blind to the advantages of wood. Switching materials would mean new tools, new skills, etc. are needed. I have a friend who is active in Germany pushing the use of this material and he talks a lot with companies in this space.
Companies seem to default to doing what they've been doing for a long time without considering alternatives. Many construction projects are actually still one-off projects that don't leverage economies of scale or learnings from previous construction projects. Construction could be a lot cheaper and much less labor intensive than it is today.
CLT could actually make on-site assembly a lot simpler and faster than it is today. Ship pre-fab components created in large scale facilities optimized to manufacture those cost effectively. Assemble on site using simple tools and processes.
The reason why economics of scale never really made sense in this context was that shipping the prefab components to the building site mostly wiped out the savings.
Ignoring the actual shipping cost (which is substantial for heavy things that get assembled into a house), it also comes with the risk of things getting damaged while en-route etc. another reason is the fact that places in reality very rarely are actually the same. They can do best effort, but things will likely still vary a little. That's another error scenario wiping out a good chunk of the savings, which fundamentally doesn't exist of you just build on-site.
I'm not knowledgeable on this new material to judge wherever this could potentially change this status-quo, but I wouldn't hold my breath either.
The regulatory landscape around home building is intense. Especially for fire code. You basically have an entire industry of inspectors whose job is to fail things that don’t match any known pattern, so getting new patterns established is quite difficult.
There is likely also some resistance to it in the home insurance space where they are incredibly data driven, so until you have data built up to justify the statistically supported lower prices of stone houses, the insurance companies will keep premiums higher resulting in non standard materials being limited to the wealthy or fanatics willing to eat the cost.
I'm doing a lot of things myself, but anything that can get dangerous or wildly expensive when I fuck it up I let skilled contractors handle.
Lab / barge-cultured wood products could potentially have really great materials properties that the natural stuff doesn't. Plywood is super useful stuff, and the best is made from more layers. The orientation of the wood fibers is flipped 90 degrees from layer to layer to give its strength in multiple dimensions. The more perfectly uniform the grain of each layer, the better quality the plywood. Voids and grain runouts create a locally weak spot or cosmetic issues. Weak spots generally don't correspond through layers, and the material generally isn't pushed to its theoretical limits in application. And cosmetically, better quality plywood reserves the highest quality layers for the outermost visible layers.
Baltic birch plywood is considered The Good Stuff and is made by essentially peeling a tree that grows pretty straight and pretty uniform. But you can imagine growing a seamless sheet of plywood that is even more perfect. Maybe one or two layers of fibers running one direction, before the next layer is encouraged to flip orientation. The platonic ideal of plywood, without needing to peel trees and stick layers together with glue.
And again, if we get freaky with the cell cultures, you can imagine cool properties where layers take up minerals from sea water that help with e.g. rot resistance or fire resistance. Or even freakier, maybe we figure out how to incorporate synthetic or lab cultured spider silk with our plywood, giving it truly novel material properties.
The low quality stuff is full of knots, warped (with very high variable humidity- some beams weigh 2x other beams). The high quality stuff is.... not as nice as maple, but certainly it's dense, uniform, and doesn't warp. From what I can tell, it's because they select the high quality stuff, then kiln-dry it and mill it.
Also if you inspect cheap 2x4s, there are often some higher quality pieces (few knots, straight-ish, not too wet) which you can then trim and plane to get decent wood.
But yeah, pine is sort of an industrial product grown fast at scale.
Pine is well suited to its use, otherwise, well, we wouldn't use it!
It's by a massive margin, the most common lumber used in construction. Its strength and other properties are well understood and all you have to do is follow the specifications and it performs great.
I mean what would even be the advantage to using other woods for home construction? Using a "stronger" wood means what? You can make your structural members smaller than 2x4? What would be the point? Walls need space for insulation and wires and pipes, there's no good reason to use a more dense wood. And it would still be more expensive! Pine is perfect for what it does because it meets the practical and engineering needs at the least expensive price.
As I understand it, you’re not taking any significant amount of nutrients when you harvest the trunks of trees and leave the branches behind to replenish the soil.
Controlled burning can also be used to speed up the process. Some species of pine trees actually require fire to reproduce.
There are questions about making the soil more acidic. Pine trees grow better in acidic soil. Correlation is not necessarily causation.
That and the maximised sunlight
Also, trees sway in the wind.
1. It's very dense
2. The first hole is usually easy enough, but consecutive holes become more and more difficult.
3. This is much less a factor of density than of silica content. Silica sands the metal. Carbide and cobalt bits can help a lot, but the silica always wins.
Worthy note: High silica wood dust, eg from ipe, may as well be considered worse than asbestos. It's evil stuff and will destroy your tools and your lungs inevitably.
Edit: while I don't know the silica content of a wood that's roughly twice the (janka) hardness of ipe, such woods also seem to drill ok, depending on the bit. Two examples are Lignum Vitae and Quebracho. The latter, I think, means axe breaker and was named appropriately.
Edit 2: it's Day of the Insidious and Relentless Typo. Nailing any of the mentioned woods is about as practical as nailing your own hammer. Either the nail will bend before making a dent, or the wood will split.
> The result is a material that has 50% more tensile strength than steel with a strength-to-weight ratio that’s 10 times better ...
Maybe torsional, compression, flex, etc. strength isn't so good?
Otherwise, why focus on the construction industry? How about airplanes? Cars and trucks?
(The original process is documented in the Nature article: https://www.nature.com/articles/nature25476)
I suspect the issue with the other use-cases you mentioned is that it's very rigid. It isn't at all ductile or bendable the way steel is. It would either need to be pressed directly into the shape you need during manufacturing or pressed into a large piece of raw stock then subtractively processed to get the shape you need.
Pressing might be economic for standard profiles like beams but it won't be for pieces like the chassis of a car.
To be clear, "pressing" here doesn't just mean a standard hydraulic press, the press also needs to be heated and the wood needs to be held under pressure for a while. You can't just stamp it the way you can with steel panels.
The more common industrial process is material called "high pressure laminate" which is your standard countertop laminate material that's only 1-2mm thick and is glued to a cheaper wood substrate.
This product is going to be extremely expensive and will not complete with existing engineered woods.
Space elevators!
Stairway to haven: Antwerp’s wooden escalators are among the last in use in the world -- https://www.belganewsagency.eu/stairway-to-haven-antwerps-wo...
How about wooden space escalators?!
I’m assuming there’s a reason this story includes a quote at the end that’s specifically about I-beams.
I don't know much about materials science, but I had a few classes about it.
Seems like their wood gets ~550 MPa in ultimate strength in tension. Seems like their material is brittle (so it behaves like a spring until it breaks), therefore you probably want a safety margin, because at 550 MPa it breaks. Note the unit is a Force/Area, you can compare materials with the same cross-section. In compression they say it's about 160 MPa in axial load, it can be more or less in the other directions (due to wood having fiber it's not the same in all directions, and there they compress it perpendicular to the fiber so they get one direction stronger than the axial load and one weaker, but I guess for a beam you mostly care about axial strength). Torsion and flexion are directly dependent on compression, shear and tension, didn't find shear. Although I'm not entirely sure how it works for materials that aren't the same in all three directions like steel.
For steel, depends on the steel but a quick search (https://www.steelconstruction.info/Steel_material_properties and https://eurocodeapplied.com/design/en1993/steel-design-prope...) says ~200 to 400 MPa in tension for yield, at which point it starts changing shape instead of behaving like a spring, then 350 to 550 MPa for strength, at which point it breaks. I believe in multiple applications they do go apply forces where the metal bends a bit and adapts to its application, but I'm not sure. Regardless, that would mean the wood in tension is equivalent to very strong (presumably very expensive) steel.
In compression, steel is from 170 to 370 MPa apparently(https://blog.redguard.com/compressive-strength-of-steel, didn't find much else easily because numbers were strange on other sources), so I guess steel would win on that one.
But this is comparing the raw strength. In reinforced concrete, you add the metal for tension resistance, concrete is there to sustain compression, so it wouldn't matter much. For beams, the shape of beams is optimised to resist in the direction it needs (e.g. the H cross-section resists to bending in one direction). But you probably can't do that with their wood (they say for now they are limited in shapes), so you'd need more material, and probably it would be stronger overall since you have more material. Question then is how much material (in weight, compared to steel) do you need (they say 10 times less but it probably doesn't take into account the shape), and how much does it cost?
I'm guessing they could also make composite beams at some points too, with not only wood in them.
Then for mechanical applications, there might be also other things that enter the game. In their paper they needed to coat the wood so it wouldn't swell with humidity. For any application with friction, not great. Also, I wouldn't be surprised if it's more sensitive to friction than metals.
Note that the numbers are from 2018, they may have improved the process.
Here's one source of data: https://hn.algolia.com/?q=stronger+than+steel
I've sort of had the opposite idea in my head for a while (many years): I wish there were a site that only talks about stuff that's already released and available to consumers. I don't want any future promises, I don't want any pre-orders, I don't want any announcements for products that will only come out in months to years, not even supposed scientific advancements that haven't even resulted in any product yet and may never[0]. I want only stuff that's available right now already.
Hearing about future stuff has only ever made me feel worse. I want to just stop hearing about the future altogether. I wish promises and pre-announcements and whatever just didn't exist.
[0]: https://xkcd.com/678
Tensile strength along the fiber direction is up to 600 MPa, which is higher than mild steel used for ordinary construction (~400 MPa). Except that mild steel is isotropic and highly ductile, i.e. it will deform by 50% or so before finally breaking, while the densified wood will snap as soon as its strength is exceeded. There are also steel grades that are way, way stronger than mild construction steel.
Flexural and compressive strength is up to half as high (300 MPa, below mild steel).
Strength in the weakest direction (across fibers) is around 50 MPa, or 1/8 of mild steel.
This densified wood is essentially a rather weak fiber composite. With careful planning it can be used instead of steel in construction, but their marketing is simply BS.
The idea here holds merit and has been attempted before. The video below is a great watch about "bulletproof wood".
This company however is using it for the facade of the building not the structure, which is kind of a yellow flag. Many fancy headquarter buildings are after some novelty to show off. Facade is not a reliable market unless they can somehow integrate their wood into curtain wall systems and other high wind load applications.
Ipe is actually not attractive for exterior structures. The wood is so dense, stains don't penetrate. Many let it age to a grey/brown patina with annual cleaning and sanding. Inventwood would be a better alternative for exterior work if they have coloring options during the manufacturing process. For Ipe, staining is expensive and time consuming due to it has to be stained like cabinetry, with two passes.
I am curious how much grain structure effects compressed wood's strength, because with traditional wood you have to either very carefully select your pieces and avoid knots in bad areas, or just super over-build a structure so that no single points are ever a failure point. Like a stud-framed house can use garbage wood because it really only needs like 1/3 of the studs to be a stable structure, the other 2/3rds are just convenience for nailing things to it and in being able to use crappy lumber without any skill or knowledge and still end up with a safe and stable structure. Versus something like a timber frame where there are critical beams holding things up that you don't want a big gnarly knot in the middle of a span.
Basics: https://www.southernpine.com/grading-methods/ and https://bof.fire.ca.gov/media/llad34j2/full-14-b-presentatio...
Examples: https://www.nelma.org/the-grade-rule-book/ and https://nlga.org/wp-content/uploads/2023/01/NLGA-GR-2022-ver...
The process involves boiling and pressing, both pretty energy-dense processes. Maybe not as energy intensive as an arc furnace, but would be curious to know how much less.
It's possible that this could replace 1950s and 1960s US made cast iron as the best possible material for large machine tools. (Lathes, mills, jig borers, etc.)
I'm assuming its wood veneer with a colored stain on some layers
>Ultimately, InventWood is planning to use wood chips to create structural beams of any dimension that won’t need finishing. “Imagine your I-beams look like this,” Lau said, holding up a sample of Superwood. “They’re beautiful, like walnut, ipe. These are the natural colors. We haven’t stained any of this.”
At least for residential, wood-framed houses, the framing material is delivered pre-cut. Even roofing beams are pre-assembled and delivered in triangles to the construction site.
I'm sure someone can figure out a program that takes a CAD design and plans all the cuts.
CLT is often faster because you can essentially just prefab it offsite and assemble it significantly faster and with less equipment and specialized workers than reinforced concrete. Steel needs steelworkers, plus concrete takes time to set and cannot be poured in all weather conditions.
While this isn't CLT I would imagine you still get most of the benefits (you can cut it to spec offsite and don't have to do anything special with it when it shows up)
It's kind of moot if the resulting product causes more emissions or is not reusable, bio-degradable or at the very least chemically inert, like steel is (citation needed).
If all of that isn't true, it's just aesthetics.
(most of what I know about this is from a video about making bamboo 'wood' products, which involves a lot of glue)
> The termite killing gas — sulfuryl fluoride — has been found to be 4,800 times more potent than carbon dioxide in trapping heat.
> When a team of Johns Hopkins scientists set out to map exactly where the gas was being released, they were startled to find that California generated as much as 12% of global emissions of the synthetic fumigant.
Their website [1] shows house built of this wood.
I think I'd expect that to work. It's not going to be better than steel, as steel is amazing for a wide range of reasons, but for something in the domain of marine ply / other engineered timber, sure.
Anecdotal, but I've been to Finnland last year and I couldn't help but see a correlation between (a) big swaths of land are covered in trees and (b) a lot of housing is build with wood.
It's honestly somewhat impressive to see huge structural elements build from what is basically a single glue-up.
So I assume that it's not actually about "wood stronger than steel", but more about (local) availability and/or logistics.
I guess those aren't as nasty as I thought, lye and sodium sulfate are pretty innocuous.
It's probably much less difficult to deal with than plastic byproducts.
If I understand correctly this process enables recycling wood pulp and waste with less inputs and less environment impact.
This sounds a bit implausible implausible. Steel is insanely strong, especially high strength steels, can be over 1000 MPa.
Here's the original paper:
http://lit.umd.edu/publications/TengLi-Pub91-Nature-2018.pdf
> The densified wood demonstrates a record high tensile strength of 587 MPa.
Yeah... ok it's 50% stronger than very low strength steel.
I think there are other problems comparing it with steel. Steel isotropic; wood is only strong in one direction. Steel has really nice and safe ductile failure modes that wood doesn't. Iron mining is not great for the environment but I doubt hardwood production is either, and steel can be easily recycled.
Seems like a great product but it feels like slightly disingenuous positioning.
Maybe (touring) skis could be a good application for this? Would be fun if somebody tried it.
No pricing mentioned though, perhaps it is too expensive.
If they can't get cheaper than steel, if they can't compete with steel, they'll probably never be more than a niche product.
https://en.wikipedia.org/wiki/Kevlar#Structure_and_propertie...
Incremental step is good news for me --- makes this making it out of the lab more credible!
That's probably why they are leaning in towards sustainability and aesthetics instead. They likely can't compete on cost.
> Class A fire rated, or highly resistant to flame, and resistant to rot and pests.
Can it be used to construct a cargo ship?