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A New Age of Materials Is Dawning, for Everything from Smartphones to Missiles

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Re: A New Age of Materials Is Dawning, for Everything from Smartphones to Missiles

#3
Interesting article, if on the advertising side of things. I've done some hobby work with some basic composites and they're really neat to play with. Even so, I itch at the idea of bolts made out of composites; there are plastics and resins that don't creep under some conditions, but I wonder if the space magic they're describing actually...works.

Re: A New Age of Materials Is Dawning, for Everything from Smartphones to Missiles

#4
> While composites might seem like a futuristic technology, in many ways, they hark back to millions of years of human and even pre-human material technology. Wood, after all, is the original composite material, as it’s composed of long and short fibers glued together by other substances—much like modern synthetic composites are often made up of carbon fiber held together by epoxy resins. Wood was a chief enabler of the success of our species, and it exhibits many of the advantages and disadvantages of composites.

Not to nitpick too much, but while wood is "technically" a composite material made up of fiber embedded in lignin, I don't think it's very useful to include it under the broad category of composite materials. Engineered woods like plywood and cross-laminated timber definitely are, but it's more useful to classify regular wood as an organic raw material rather than a composite.

The first composite material humans had any experience with was probably silcrete. It's naturally occurring but ancient humans figured out how to strengthen it by heat treating it in a fire (80-160 kYa). The first time humans intentionally made a composite material is adobe/mudbrick (11 kYa), wattle and daub (6 kYa), plywood in Mesopotamia (5.4 kYa), cob (4 kYa), and finally Romans developed something resembling concrete (I dont remember kYa).

Re: A New Age of Materials Is Dawning, for Everything from Smartphones to Missiles

#5

> While composites might seem like a futuristic technology, in many ways, they hark back to millions of years of human and even pre-human material technology. Wood, after all, is the original composite material, as it’s composed of long and short fibers glued together by other substances—much like modern synthetic composites are often made up of carbon fiber held together by epoxy resins. Wood was a chief enabler of…

> Not to nitpick too much, but while wood is "technically" a composite material made up of fiber embedded in lignin, I don't think it's very useful to include it under the broad category of composite materials. Engineered woods like plywood and cross-laminated timber definitely are, but it's more useful to classify regular wood as an organic raw material rather than a composite.

Why would defining it as a raw material be "more useful"? Why is defining it as a composite "less useful"?

Re: A New Age of Materials Is Dawning, for Everything from Smartphones to Missiles

#6

> While composites might seem like a futuristic technology, in many ways, they hark back to millions of years of human and even pre-human material technology. Wood, after all, is the original composite material, as it’s composed of long and short fibers glued together by other substances—much like modern synthetic composites are often made up of carbon fiber held together by epoxy resins. Wood was a chief enabler of…

I think they’re just trying to make composite more relatable to the Everyman without actually understanding it themselves. At least they’re trying.

Re: A New Age of Materials Is Dawning, for Everything from Smartphones to Missiles

#7
post #5

> While composites might seem like a futuristic technology, in many ways, they hark back to millions of years of human and even pre-human material technology. Wood, after all, is the original composite material, as it’s composed of long and short fibers glued together by other substances—much like modern synthetic composites are often made up of carbon fiber held together by epoxy resins. Wood was a chief enabler of…

> Not to nitpick too much, but while wood is "technically" a composite material made up of fiber embedded in lignin, I don't think it's very useful to include it under the broad category of composite materials. Engineered woods like plywood and cross-laminated timber definitely are, but it's more useful to classify regular wood as an organic raw material rather than a composite. Why would defining it as a raw materia…

Yea from a material science perspective, wood seems to obviously be a composite.

Re: A New Age of Materials Is Dawning, for Everything from Smartphones to Missiles

#8

> While composites might seem like a futuristic technology, in many ways, they hark back to millions of years of human and even pre-human material technology. Wood, after all, is the original composite material, as it’s composed of long and short fibers glued together by other substances—much like modern synthetic composites are often made up of carbon fiber held together by epoxy resins. Wood was a chief enabler of…

Kinda feels like you're missing the point of the quoted sentence. That is, it's not that wood is actually a composite material as we define it now, but that wood has the characteristics of a composite, i.e. different substances intertwined in a way to give better properties than any individual material alone, and going with the theme of the article, this is a direct contrast to materials like steel or plastic.

Re: A New Age of Materials Is Dawning, for Everything from Smartphones to Missiles

#9

> While composites might seem like a futuristic technology, in many ways, they hark back to millions of years of human and even pre-human material technology. Wood, after all, is the original composite material, as it’s composed of long and short fibers glued together by other substances—much like modern synthetic composites are often made up of carbon fiber held together by epoxy resins. Wood was a chief enabler of…

Kinda feels like you're missing the point of the quoted sentence. That is, it's not that wood is actually a composite material as we define it now, but that wood has the characteristics of a composite, i.e. different substances intertwined in a way to give better properties than any individual material alone, and going with the theme of the article, this is a direct contrast to materials like steel or plastic.

The other important property that wood shares with modern manmade composites is that it is anisotropic - i.e., it is stronger in some directions of force than others. You can use bodyweight to snap a short grain board that would, if it were long grain, hold up under a ton or more.

Re: A New Age of Materials Is Dawning, for Everything from Smartphones to Missiles

#10

> While composites might seem like a futuristic technology, in many ways, they hark back to millions of years of human and even pre-human material technology. Wood, after all, is the original composite material, as it’s composed of long and short fibers glued together by other substances—much like modern synthetic composites are often made up of carbon fiber held together by epoxy resins. Wood was a chief enabler of…

Wood was a chief enabler of the success of our species

Wood was the chief enabler of trees. Trees have to be big, strong, lightweight, and bendable. Homogeneous materials won't work for that application. You need a composite. So evolution invented one.

Even more amazing: Trees 3D print themselves out of carbon dioxide.

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