TL9+ Wood [Ultratech]

[AlexanderHowl]

Originally Posted by malloyd

Probably not very much. Those numbers are nonsense (or I suppose more charitably measured against some particularly unimpressive wood, it comes in a lot of varieties). The best case for densified wood is you remove everything but the cellulose and collapse that to a solid block - which of course gives you the same properties as a block of a cellulose plastic. That's not a new material, but generally hasn't found many applications.

What people are actually hoping for from densified wood is that it will be cheap. Cellulose bioplastics are on the more expensive end of plastics, if they were dirt cheap, they probably would have more applications, not as wonder materials but for the same kind of large scale applications we see other cheap materials (like say wood, or concrete, or mild steel) used for.

From the recent reports, the laminated densified wood is as strong and tough as high quality steel at the same thickness, but it is 1/3 the mass and costs the same per mass (three times as much as steel of the same thickness). It is much much tougher than plastic because of the chemical and mechanical changes created by the process.

[Anthony]

Originally Posted by AlexanderHowl

From the recent reports, the laminated densified wood is as strong and tough as high quality steel at the same thickness, but it is 1/3 the mass and costs the same per mass (three times as much as steel of the same thickness). It is much much tougher than plastic because of the chemical and mechanical changes created by the process.

The normally correct thing to do when you see numbers compared to steel is to immediately ignore them, because it always heavily depends on what properties you're talking about, what sort of steel you're comparing to, and steel isn't terribly impressive for a lot of properties, so using that comparison mostly means the person talking wants to sound impressive.

[AlexanderHowl]

It is comparable strength to carbon fibers per mass, but it is 5% the cost. They are anticipating using it to replace the structural components of cars.

[Anthony]

https://www.scientificamerican.com/a...-s-super-wood/ appears likely to be the article being talked about. The indicated performance looks comparable to HDPE.

[AlexanderHowl]

Not quite, densitied wood is 3x the density of HDPE and around 10x the strength of HDPE.

[Anthony]

Originally Posted by AlexanderHowl

Not quite, densitied wood is 3x the density of HDPE and around 10x the strength of HDPE.

The quoted performance for bullet resistance is "slightly worse than a similar thickness of Kevlar". That is inferior to UHMWPE (often just referred to as HDPE) of the types used for body armor.

[AlexanderHowl]

Sheer strength is different from tensile strength and compression strength. The compression strength of densified wood is 50× that oak from what I can gather from the litersture, while the tensile strength and sheer strength are around 10× as much (inferior to Kevlar).

[Black Leviathan]

Minimalist furniture.

5 lb dinner table that can hold up a full dinner and the pressure of 5 adults leaning on it. Easier to move, less damaging to flooring, cheaper to ship.

[ericthered]

I'm looking at what I believe is the original paper.

The various number increases highlighted are in the range of x7.5 to x12. I'm not sure where the x50 is coming from.

Strength is not a specific term. There is tensile strength and there is compressive strength, and even together they don't tell the full story. I hope someone better at materials science than I can look at the numbers in the paper. I don't doubt its a nice substance, but it doesn't look anything like the holy grail of building materials to me.

What would I use it for? Study furniture is the application I immediately think of. I don't think it enables any new structure types, just different materials replacing existing ones.

If its really practical and cheaper than structural steel, It will get incorporated into all sorts of things. I don't think it will replace tools, but you'd see ladders, furniture, buildings, and bridges made out of it.

If it performs as hyped, Someone will build a yet taller skyscraper with it. And try to break some bridge length records.