The History of Carbon Fiber

We will give you our new email address at the end of this episode, but just keep in mind it might take a while for that address to actually take effect. So if you really have to get in touch with us, use Facebook or Twitter for the near future, or tumbler. Good good point. So what Matt had to say was, I'd like to hear a show about carbon fiber and the other compositive exotic materials used in aerospace and other

modern vehicles. I work with the machines that convert this stuff from spools into airplanes and rockets, so it's a topic that is interesting to me and maybe a useful reference episode for future topics. We agree, carbon fiber fascinating stuff. It is. I didn't even realize how fascinating it was until we in fact started doing this research, and because it is so fascinating, and since we are splaying this into two episodes, we'll probably have to look at other

exotic materials in another one. Well, we'll make some mention of stuff that is similar to what carbon fiber is, but we're really going to focus on carbon fiber because it's there's a lot there. Oh yeah, there could have probably been way more than two episodes about carbon fiber if we had really gotten into gritty details about about different uses for it and exactly if we had gone into the history of this is the first vehicle to use. If we had done that, this would have been a

three partner easily. But but if you're not fans, we didn't go into that kind of minute detail. We're going to tell you in this episode about the history of developing carbon fiber. In our second part we'll look more into how it's actually made and the process that that you have to go through in order to get a raw material to turn into carbon fiber, and some of the challenges and benefits thereof. Yes, So, first, what the heck is carbon fiber. It's a material made up of

thin strands of crystalline carbon. Well, there you go, episode over, Thanks guys. Yeah, but no, we're gonna we're gonna give a little more detailed than that. So the thickness of an individual strand of carbon fiber can be thinner than a human hair by by many factors. Oh yeah, yeah, and um, if you're wondering, yes, it is in fact structurally similar to graphine and carbon nanotubes, the difference being in the way that the sheets of carbon atoms are

are packed and interlocked. Yeah, this is one of those amazing things about carbon. You know, if you put the carbon atoms in one formation, you get this very soft material that you would find in pencils, for example. You put it in a different kind of modular combination and you get diamond about as different as to substance as convene. Right, So it really shows that just by changing these these

orientations you can really change the properties of this one material. Well, those little strands, those strands that are thinner than a human hair, can be twisted together to make a yarn like material and then woven like cloth, which can then be laid in a mold and then coated with resin or or a plastic So that it will take on

a permanent shape. So, right, the coated stuff itself is frequently referred to as carbon fiber, but you may also see it more precisely referred to as carbon fiber reinforced polymer. And that's it rolls off the tongue, right, We're just gonna call it carbon fiber, so, uh, forgive us for taking a shortcut. But it has a lot of interesting properties. Right. So for one thing, it's five times stronger than steel and twice as stiff as steel, but it's lighter than steel,

about two thirds lighter by volume. Also about eight times stronger than a loominum or aluminium depending on where you live, um, which is really handy since aluminum is lower weight by volume is offset by its lower strength, meaning that you have to use a lot more of it to get stuff done. Right, So, now you've got this new material that you can use instead of that in lots of different products, and as long as it meets the needs of whatever that product is, you are getting a benefit

of something that's stronger and lighter. That's pretty amazing stuff. So who does use this? Well, the auto industry uses a lot of carbon fiber, right, it's main mainly there to make the components of a car lighter and stronger, which obviously I mean that's the properties of the material, so that makes sense to transfer it to the final product.

So why would you want a lighter vehicle? The main reason is cause it takes less power to move a lighter vehicle than a heavier vehicle, So that means that you can make a more efficient engine. You're using less energy to move the actual vehicle, and as long as that vehicle has maintained its strength, so you haven't compromised the safety of the people who are in the vehicle, that's a good thing. Oh sure, carbon fiber usually makes the car actually more resistant to impact than it would

be with just regular steel components. And in terms of that efficiency, um according to the oak Ridge National Laboratory, which is this huge lab run by the Department of Energy, you can make a cart more efficient just by trading out a steel body for a carbon fiber one. So that means that you would end up over time saving lots of money and fuel costs, not to mention the environmental impact of having to consume less fuel to get around. Uh So these are some interesting uh uses of carbon

fiber is not the only one. There are a lot of others will talk about. For example, we you know, Matt mentioned aerospace, a big, big industry that relies on carbon fiber. Yeah, yeah, um, and a lot of really mundane kind of things like golf clubs or bicycles, fishing rods, sailboat masts, and wind turbines. So the thing about carbon fiber is, well, I guess we should go into the history and then I'll tell you what the thing about

carbon fiber is. That's foreshadowing so earliest use of carbon fibers. The interesting thing here is that the earliest use I could find predates their applications in any of the industries we just mentioned. And in fact, it wasn't even used to build something like a structure. It wasn't used for its strength or lightness. It was used for an entirely different property that's inherent with carbon fiber, which is its resistance to heat. Thomas Edison, Yeah, a different kind of light.

Yeah yeah, exactly, not light as in less heavy light as in let there be so Thomas Edison, who, of course we know, beloved Internet darling, one of the favorites. I guess I forgot to boo when when we when you said his name right right, I'm sorry, Okay, well we'll we'll put it in there for you Internet boo. Yes, Thomas Hays in the Elephant electrocutor uh who did not personally do that, but still use them as filaments for early light bulbs way back in eighteen seventy nine because

of that high tolerance for heat. Now they can also conduct electricity, but they have a high resistance. If you remember, resistance is what we'd call the the the kind of opposing element that keeps electrons from flowing through a material smoothly. So if you have a high resistance and you want to try and get electric electrons from point A to point B, you're not getting as many to point B as we're leaving point A because some of those are

converted into that electrons converting into heat. You're losing it through that resistance. I'm oversimplifying, but this is basically what's happening. So with light bulbs, that's exactly what you do want. You want to have something that's heating up, and as it heats up, it starts to give off photons light particles.

That's what lets us see that light. And of course, in this case we're talking about light that's in the visible spectrum wouldn't be much used to us outside of at So you end up using this material that has a resistance to high temperatures, because if it didn't, it would just burn up. You know, you would get light, but it would burn up, and then your light bulb would be useless. That's just a fire, and that's less

used exactly. And while you would try and create a vacuum within the light bulb so you couldn't really burn burn, you would still end up having the material itself deteriorate really quickly and the light bulb would be broken. And so anytime you know, when you have an old incandescent light bulb and you hear it, they'll pop and then you shake it and you can hear the little chicken. Yeah, that's the filament that has given out because it has

been worn away so much. So anyway, the carbon fiber tended to be a really good candidate for this filament, and that's what Thomas Sen used. So how did he create carbon fiber? Well, he carbonized something, which means that you're taking one material and you're converting it into these these carbon atoms, these crystalline structures of carbon atoms. Now specifically what Thomas Ysen was using was cotton and bamboo, different different ones for different types of light bulbs. Experiment

with a lot of different materials. Sure, but but carbonization is also how we make charcoal. We we carbonized wood. That's exactly right. And so if you wanted to carbonize wood, if you wanted to make your own charcoal, you would have a few steps. One is that you want to remove all the moisture you can from the organic material, usually through evaporation and heating. So with would we call

it seasoning. And you may remember that just in our recent podcast about the HMS victory, they would season would in order to get as much moisture out of it as possible and made the wood stronger as a result. In this case, it's not to make the wood stronger, it's really just to get rid of all that moisture. And the next you would increase the temperature to induce pyrolysisis it's a basic chemical change brought upon a material

through the application of heat. Okay, And what's important in this chemical change is that you don't allow any ox gen to come into contact with the material during the process so that it can't burn right. Because, as we remember, the three things you need are you need you need fuel, you need oxygen, and you need heat to create fire. So if you take any of those three away, you

don't have fire. So by taking the oxygen away, you don't have to worry about prematurely burning your material, and you can convert it to carbon without it actually catching fire. Very important in any application, specifically for charcoal, because you don't want to burn it before you burn it right, Otherwise barbecues over before it began. Yeah, I've been in some states that some prey sad barbecue with organic material.

That means getting all this stuff carbon converted down to carbon while the other stuff like water vapor essentially just kind of evaporates away or kind of vibrates away. Technically, the atoms that are other than carbon in the material are expelled during the processing. Yeah, you can kind of think like carbon. They're allowed to stay at the party. Everyone else is encouraged by the bouncer to leave. So, uh depend to those parties and a lot of chemical

processes go on through pyrolysis. There's one called isomerization. That's when a molecule gets rearranged into another molecule that has the same constituent atoms but a different physical structure. You know, like I was mentioning earlier, the you know, the way you construct carbon atoms together can't depend on that that determines what properties that material has pencil, lead or diamonds. Ye, same thing with any other kind of molecule. You just, well,

not any but different molecules. You rearrange the structure of the molecule, you end up with stuff that has very different properties from each other. Which is another fascinating thing. You say, all the basic ingredients are the same, but just by the way you arrange the atoms within that molecular structure, you change the actual properties of the overall substance. This is what I think is awesome about science. I don't fully understand it because I'm not a chemist, but

I really find it fascinating. Anyway. Another thing that you would have going on through pyrolysis, it's called transfer hydrogen hydrogenation. This is where you can tell I'm not a chemist because I can't say any of the words. But this is the addition of hydrogen as one would imagine to a molecule from a source other than from hydrogen gas, which is not the easiest thing to get hold of because again, hydrogen is usually uh captured in some other

kind of molecular bonds. It gets pretty buddy buddy with most other things. Yeah, it's um, it's it's just a gregarious kind of atom. It likes to hang out with budlies. So what you're left with is carbonized material. So in the case of cotton or bamboo, it's very fibrous in nature. So then you have carbon fibers again not meant to know, weave together to make some sort of material that's stronger and lighter than steel, but still had it very good use.

So these were the fibers that would conduct electricity. They had the high resistance. You lose some of that energy as heat, but that's exactly what you want, so you're not not losing it so much is converting it over to heat to create light. Um. This is actually called incandescence, where you heat up a material enough so that it starts to give off light, hence the name incandescent light bulbs. And you've probably seen this in multiple applications, not just

incandescent bulbs. I assume most of our our listeners have seen an incandescent bulb, even though they are becoming more and more rare. But in any material that has heated up beyond it's that limit, you start to see it glow, unless, of course, it's flammable and it's in the presence of oxygen, in which case you saw it catch fire. So that's exactly why Thomasson decided to use this and ended up

being a success. It took some experiments to get it just right, and even then, um, you know, obviously over time we made great improvements to the light bulb using different types of material as filament, not just cotton or bamboo, carbon fibers, but that was the very first application of carbon fibers in any kind of manufacturing process. Now we've got a lot more to talk about in the history of carbon fibers, but before we do that, let's take a quick break to thank our sponsor. And we're back.

So we're still in the late nineteenth century. This is eighteen eighties six and I still can't believe that for such a space age quote unquote space age. Yeah, yeah, it's to the nineteenth century. Yeah, now granted again used for different purposes, but still it's when you hear carbon fiber that sounds to me like maybe the nineteen seventies was where it got started, but no, I was completely wrong.

So you have the National Carbon Company, which was the first company to make synthetic carbon, and it merged with another company called Union Carbide in nineteen seventeen, and eventually that company became Union Carbide Corporation in nineteen fifty seven. Now, the whole purpose of this was to make carbon five for things like light bulbs, so we're still in that stage.

And meanwhile, in the nineteen thirties he had engineers who began to experiment with fiber reinforced composites or f rps, which fiber reinforced composite to f r P. Uh, it technically stands for fiber reinforced polymers, but still it confuses me. Anyway, This is a composite material made out of a pattern of polymers that are reinforced by fibers. The fibers themselves are needed to enhance elasticity and strength of this plastic material.

So the first record use, according to oak Ridge National Laboratory, was for a boat hole so we've you know, you've seen fiberglass boats. I'm sure. I mean that there's a very common thing for small boats in particular, seeing fiberglass boats. That's essentially what we're talking about. So fiberglass is used

in a lot of different applications today. It's not the same thing as carbon fiber, but the the process will I mean not the process, but the overall outcome using yeah, exactly, using fibers to reinforce a structure, uh is is very similar to what would end up being used as in the carbon fiber industry, especially when you have the goal of making something very strong and very light weight exactly. So by the nineteen forties, the defense industry began to

get really interested in f rps for obvious reasons. So the search was on for new types of fiber that can make stuff stronger and lighter, and a lot of work and material science was dedicated to finding out whether the theoretical strength of certain materials could translate into practical use.

So what was happening was that scientists were studying various materials and they would say, all right, based upon the molecular structure of this material in theory, it has x amount of strength compared to some other material, and why amount of weight by volume compared to some other material if we were able to to manufacture it properly, and

so the difference between theory and reality. Often there's a gap there because we just don't have the perfect way to manufacture the stuff that is theoretically possible, or to manufacture it in a way that is uh less than completely expensive. Yeah, this, especially early on, that is a huge challenge because you often have to invent new ways to create material. So that means that you have to spend a lot of money in research and development and

and to build specialty equipment to make that stuff. It's one of the reasons why carbon fiber is not as uh plentiful as it could be. But we'll talk about that more later. Yeah. So back in the nineteen fifties, there were three really big drivers in the United States that pushed the development of these carbon fibers forward. That's true. So you had the industrial demand for lightweight, strong material, which included industries like aerospace, electronics, sports equipment, that kind

of thing. Then there was the work in solid state materials that predicted high potential crystal strengths for certain types of material. This is what I was talking about just a second ago, where people were doing this kind of theoretical work saying, hey, if we just rearranged stuff this way in theory, it should be even stronger and lighter. Let's just find a way of making that happen. The math worked out and the physical process would follow. That's

exactly right. And then the third one was that and this is probably the most important driver. During the nineteen fifties, the U. S. Economy was going like gangbusters, y'all. So with that kind of bounty there was doing so well that there was the ability to afford in investing in research and development and pushing these kind of technologies forward. Even if they had an initial high price to get into it, we could afford to do it. So that

was a big driver. Actually. So we get to the years of nine to nineteen sixty, that's when we had companies I'm merrily the Union Carbyte Corporation previously mentioned. Yep, they began to discover practical means of using carbon fibers as reinforcement. Those f rps we were talking about similar to that. So these carbon fibers didn't come from cotton or bamboo, right they were. They were using materials like

rayon or poly acrylon, nitrial or pan. Yeah we're gonna say pan because I kind of enjoy saying poly acryla night trial. I'll never be able to do it. My my mouth parts don't work that way. But no, carbon fibers from these are made from precursor fibers, which is made from you know, the ray on, our our pan. So the precursor fiber. We we use precursor as the term for stuff that you're going to convert into carbon fiber.

And that at Loan like, the precursor stuff had its own manufacturing processes, right you you had these are synthetic materials that we had to create first that then we would create into carbon fibers. So it's a it's a two step proces us in a grand overview, Yes, many smaller steps within exactly, which we will talk about in our second episode trust us for now. Yes, so, but the important thing here to remember is that it's not like you would go out to the fields and get

some rayon. You have to make the rayon first and then you convert the rayon into carbon fiber. That just cracked me up. Because the mental image of Fields of Rayon was was a circle of hell. According to me, the Fields of Rayon I think would be a great name for a band. Yeah, I'll get on that. But the the important thing here was that using these types of precursor fibers were what allowed them to create the

different shapes that carbon fiber could come into. They were they were really well formed for that sort of stuff. They were already strong and easily manipulatable. Yes, And if you want to learn more about the history of the Union car By Corporation and its role in this, I recommend going to a c s Oregon has a lot on the history of carbon fiber development, goes into a huge amount detail. And again, if we were to go into as much detail as some of these sources do,

we'd be doing like a five part series. And I think some of you guys might get a little antsy uh yeah. I I did want to mention in nine three that there was a way to make carbon fibers from petroleum pitch debut um and those are those are so many solid polymers kind of kind of like tar. Yeah, yeah, And that was that's different obviously because you can actually find tar in nature, this was not something that you would have to first create the polymer and then do

the carbonization on it. You could get the actual stuff and then separate out what you needed and then do the carbonization on that um And they experimented with lots of other materials to try and manufacture carbon fibers. That included polyesters, polyfinal alcohol, and phenolic resins yep. But it turned out that Pan, Rayon and Pitched the first three they really concentrate on, we're the most useful for creating high strength material. So so it turned up their their

initial impulse was exactly what made the most sense. It also made the most sense from a dollar standpoint, like the having the manufacturing industries that are already established for at least Rayon and Pan meant that it was less expensive than to create something out of whole cloth, and petroleum pitch could be a byproduct of the petroleum industry, So that's kind of a that's kind of a gimme, right.

So getting back to those drivers we were talking about, the two industries that drove the carbon fiber development the most in those early years were the aerospace industry and the defense industry. So you had some outside crises like the oil crisis that affected the pace of development. And now we've got a lot of different industries that have a vested interest in creating lightweight, resilient materials for products, and carbon fibers receive a lot of attention as a result.

You can imagine aerospace being the big one because we all know the heavier stuff is, the more expensive it is to try and get it out into space, the more fuel you need to get it to escape Earth's gravity so we can get into orbit. So especially these days, every dollar counts, so and obviously you want it to be really strong material because of Yeah, because because space, as we have established numerous times, is trying to kill you.

So you want to make sure that you have a nice strong barrier between you and space and and the deadly deadly space. So uh yeah, obviously a big important driver. And of course we're getting right into that era to where the United States and the Soviet Union both were racing against each other to try and get people into orbit and to get people to and from the Moon. So it was there were a lot of incentives to develop this kind of material. Now there's some problems with

carbon fiber. They have nothing really to do with the properties of the material. It's health. And one of the big problems is that there are only a few companies that actually produce carbon fiber material. So the price of carbon fiber is still relatively high, which limits its use in consumer goods or just drives the prices of those goods way up as a result. So yeah, only the the more affluent can afford those type of those type

of products that incorporate carbon fiber. Yeah, the last time I checked, I think cars that incorporate a lot of carbon fiber in their bodies are still running around the hundred thousand dollars starting price range. Yeah, I mean they tend to be really high performance vehicles anyway, because if you're gonna go with that, you might as well go all the way. It's not just a civic engine tossing. But still, your your point is is very very valid.

It's according to oak Ridge, there are three Japanese companies that make carbon fiber, four that are in the United States and European countries, and then one Taiwanese company and that's it that produce carbon fiber at least on the industrial scale. So when you have a limited supply. You know, each of those each of those companies has a limited amount that they can produce just based upon their their facilities. Right, so if you need more than what can be made,

you're kind of stuck. You know. Anyone who wants to make anything using carbon fiber is kind of limited in where they can get that raw material. Oh sure, And part of the reason that so few companies produce it is that there are huge challenges in in actually producing this stuff. Yeah, so one of them is that you first have to get the precursor fibers. That's that's step one, right, You have to have to create these precursors in order

to to tarma into carbon fibers. So either you either you're buying it from some other company that manufactures it, or you're making your own. But if you make your own, that means you need two sets of manufacturing plants. Usually you need one that's dedicated just to creating the precursors and one that's decayed to carbonization. Now, some companies, like the Japanese ones, have been co locating facilities so that you have no real distance between the precursor facility and

the carbonization facility, saving at least a little bit of money. Yeah, but you know, not everyone has that luxury of being able to build, you know, twice the facilities to make one product. That also is another reason why the why we have the expense. It's not just that, uh there's so relatively little of it to go around, but also that it does take this very involved process to actually

make the stuff. So um, other companies have actually bought up old textile plants and used them to produce the precursor fibers. That is fascinating. Yeah, I'm wondering. Uh actually my my uh my grandfather on my father's side worked in such a textile plant, which I believe is being converted over into something like that. So that's kind of interesting. But one of my grandparents was also in textiles. So now I now I'm curious. I need to look up

the plant in Pennsylvania that he worked in. The one in Georgia that that my grandfather worked in once had its roof ripped off by a tornado. But that the different podcasts entirely. So another Yeah, I guess I'll have to wait till we until it comes back around again.

Uh that was just for you Internet. So another strategy, uh as far as the manufacturing and sale of carbon fiber goes, is to include post materials processing with the production facility, which means that instead of just creating raw carbon fiber, which you would you can imagine like think of an enormous spool of thread. I mean, it's just the huge spools that have this thread that again is thinner than a human hair wounds are. In some cases they're all kind of um braided together to make to

make a rope. Yarn, Yeah, like yarn, a rope. You could just buy that stuff, just the raw material there once it's been produced, but then that means that whatever you are making, you have to have the facility to be able to take that raw material and shape it or or otherwise post processes and then coated in whatever resin you want. So some of these companies are eating that post production facility where they can do some of the treatment ahead of time so that it's a lot

easier for other companies to convert this into products. So that way you remove a necessary step that the other company has to do and make it a more attractive product. So that might include weaving the fibers together, braiding them or treating them with those resins for molding, so that you know you're not necessarily molding the stuff already, you're just pre treating it so that it can be molded faster once it gets to whatever company is buying the

raw material. That's the other reason why this gets expensive, right, because not only do you have a two step too big step process in just producing the carbon fiber itself, then you have the whole manufacturing process of turning the carbon fiber into a useful product. So every time we

add another process, you're adding to the cost. So, uh, Anyway, it's pretty cool idea to try and pare all this together to help make carbon fiber a more attractive option because obviously the demand is there, it's the supply that we're trying to to perfect. Right. So this is about where we are going to end for today's episode, But when we come back next time, we're going to go into detail about that manufacturing process, why it's so expensive, and what's being done in the industry to try to

make it less expensive. Yeah, it's a really cool process, and I'm glad that we decided to make this two episodes because I really want to be able to explain and and go into exactly what's going on behind the scenes. It's pretty neat stuff. So first of all, Matt, thank you so much for your suggestion. We'll be thinking you again in our next episode, so you know you can. You can coast along for two episodes of thanks and everybody else who wants to be like Matt and send

in suggestions do so on Facebook, Twitter, and Tumbler. Our handle is tech Stuff hs W. Our email address will be tex Stuff at how stuff works dot com. But I just can't guarantee that it's working right now. Test email. Let us know. Just say, hey, text stuff, I love you and I've never written before, or something along those lines, but make it nice. That would that would be preferable, Yeah, because I'm going on vacation, y'a. Also, it's gonna be

Laren who gets all the emails. That would be really preferable, because please do that please. That'll just mean that when I get back, I'll have five unready emails from listeners. Hey, you know what, I'd like to have that problem. So anyway, that wraps up this episode. We'll talk to you again really soon for more on this and thousands of other topics. Because it has to work. Dot Com