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um well tonight we’ll be talking about composite materials composites have been around for a long time they’ve been in the news a lot in Seattle recently if you do certain airplane and that’s actually a really exciting development and I’ll actually address some of those things that are going on with those and where we see composites going in the future so it’s a quick overview the introduction about materials and why least I think they’re important the different types of materials some of their properties and then really start talking about composites what’s good about them what can we need to learn more about them and then where might we be able to take them and I didn’t know nova had the same or not the same for words before words there but I try to do is make them stronger stiffer smarter and safer for applications in aerospace and automobiles and things like that so why do we need why do we need new materials okay well if you look at history of man it was the Stone Age the Bronze Age the Iron Age and then went into the graduate see this actually works or not I just wanna say one or two just one word yes we’re listening you’re so you plastics so as a material scientist that’s one of my favorite movie clips and you can see the polymer age or plastics really started there and was taking off in the 60s 70s 80s since then you know the number of materials has just expanded tremendously in the last 50 years and now people will say the silicon age information age who knows where we are next but all of the technology is really limited by what materials we have available to make our tools or airplanes or our cars or our space bridges in the future maybe so our space elevators so classically we’ve looked at things like metals ceramics polymers or plastics and some typical applications of them and yet there’s many things made out of the same thing okay a container to hold a beverage they make a lot of metal glass and plastic why do they make them all of all those different things when it’s all doing the same thing so it just shows as many choices there and whether it’s due to aesthetics maybe you think it tastes better maybe it’s cheaper all those things go into choosing the right material and so if you look at the different types of materials in terms of metals they’re fairly strong their doubly called ductile they usually bend before they break which is a good thing in many applications they’re good thermal and electrical conductors are wires and things like that they’re opaque and generally have that metallic look to them they’re shiny polymers ah is a wide variety of polymers both natural polymers like our skin and our hair to the man-made polymer your milk jugs and things like that a little bit of the type of bonding that takes place in them is mostly a covalent bonding where they actually share electrons and this gives them certain properties many polymers are soft compared to metals and ceramics they have a low density which means they’re lightweight which is good the generally insulators and they have a wide variety of optical properties again due to their atomic arrangements and things like that ceramics on the other hand are usually ionic or they also can have a van like bonding they are generally very hard and very brittle things like our beer glasses or the diamonds in our rings all examples of ceramics most of them are insulators diamond is kind of a funny exception to that rule and then we come down to composites well they’re not one of those three they’re generally a mix okay so a composite is when you take two different materials mix them together to make a new material and now this new material isn’t just an atomic mix of a material like an alloy or a solution you actually have two distinct phases or two

or more distinct phases that retain some of the properties of what you mix together so it’s a little bit different than just you know mixing you know alcohol and water together or things like that to get a mixture so with composites the objective is really to try to take the best properties from two different materials put them together and use what’s called the principle of combined action to get sort of an average of the properties which is not available in either one of the materials by themselves and so mostly I’ll be talking about what are called polymer matrix composites tonight so we’ll take a polymer and then will reinforce that polymer with a ceramic or another polymer in some cases and so you can get sort of the flexibility and the weight lightweight of a polymer plus the strength and the stiffness of a ceramic in a new material and nice thing about composites is that you can sort of engineer your material by the choice of what you’re putting together and how much polymer and how much ceramic you put together the orientation of the ceramic within the polymer as well so there’s a lot of flexibility there to come up with surgery designed material properties so it’s looking at strength of the different materials we’ve talked about as we said metals are fairly strong and it depends whether we’re talking about steel or gold ceramics there’s a variety there the technical ceramics are fairly strong polymers are down here in the strength and composites go over a very wide range because it’s what you’re mixing together you know wood is actually a composite it’s a composite made at a two or more different types of polymers actually so down here it’s actually you know a mix of polymers some of these is CF RC is carbon fiber reinforced composites gfrc would be glass fiber reinforced composites and so you can talk about the different reinforcements you use and you can see well ok composites are maybe as about as strong as steel but generally hear that composites are actually stronger than steel right well it depends on how you measure that strength because if we look at weight you can see here the density and this is a log scale so this is actually it’s ten times from here to here metals are all quite heavy ceramics little less dense polymers are very light and composites are down there if you use the right mixture composites and you know here we actually are lower than polymers and that because you may have things like porosity in your composites you have little bubbles that actually make it a less dense material but if you think about a lot of the applications especially like aerospace and actually transportation what’s very important isn’t just strength or just wait it’s the combination you want something that is strong and like so if you look at composites you know on the base of just strength and stiffness there’s not a clear advantage but if you look at it in terms of weight there’s a huge advantage so if you say well how much force will one pound of composite holes compared to one pound of steel then you can really get a better measure when weight is an important property so we look at these that we call specific properties where we take the stiffness or the modulus and divide it by the density or the strength and you divide that by the density and here’s just a quick example showing that hears us a schematic say of one cubic inch of steel and one cubic inch of composite so it’d be one inch by one inch by one inch and you look at the densities of those this is a high strength steel this is a high-strength composite you know very high density for the steel we look at the strengths there but now if you divide the strength by the density you get this specific strength and here you see steals about 22 composites about a hundred so composites in that case would be five times stronger than steel on a weight basis so that’s where we you know there’s this great incentive to use composites and things like aerospace and

transportation where weight is a penalty so why do composites have this property well I passed around some different composites and some of the raw materials that go into composites and tonight I’m talking about fiber reinforced composites so there’s some fabric looking samples going around there’s a white one that is a glass fiber weave there’s a black one which is a carbon fiber or graphite fiber weave and then there’s a red and white one which is the red fibers are actually Kevlar so same thing as uses some of the bulletproof vests and the white fibers are the glass fibers again so you can design just the fabric you’re using as well to have certain properties by mixing two different fiber types together but you can see the fibers by themselves you know they’re very flexible if you pull along pull them in the direction of the fibers you’ll see that they’re very strong but if you’re off access a little bit or push it together you’ll see it folds there’s nothing holding those fibers in place so it’s sort of like a rope try to push something with a rope it doesn’t work very well so in a composite you need something called the matrix and that’s what comes and surrounds all the fibers and actually helps transfer the stress between the fibers I didn’t have a lot of samples of the matrix but here is one that I have and I can pass it around here this is just the material that the plastic that goes around the fibers na this is a sample of epoxy same thing you would get in the five-minute epoxy two of you squeeze out but a little bit higher tech higher properties for aerospace grade resin and you would put this around the fibers and then after it cures and sets up and becomes hard you see the results of that and the other samples I’m passing around which are now very stiff strong and lightweight so I can go ahead and pass that around if you want I also put in a sample of just metal so you can sort of feel the weight difference between the composite and the metal and also there’s a sample of what’s the honeycomb composite where they’ve taken aluminum and it looks just like a honeycomb and a beehive and then bonded on to thin layers of composite on the outside and you see that it’s very strong and very stiff and that’s very representative of what you’re walking on when you’re in an airplane the floors of airplanes and a lot of luggage compartments you know they’re thick but they’re very lightweight because they’re made out of these honeycomb structures so what is it gives them the strength it’s the fibers you those fibers are very high strength and stiffness their carbon or glass or Kevlar which is a very specific polymer compound they have very small diameters the fibers here shown in electron microscope the bar here from here to here is 50 microns which is about the radius of your hair hair is 75 to 100 microns in diameter so you can see these fibers here generally in the order of 7 to 10 microns so let’s barely even see one of them with your eye if at all and the smaller you make something the stronger it is and the reason for that is strength is usually limited by defects so cracks or chips or scratches so an example of a chain the chain is only as strong as the weakest link okay so the more links you have the greater the probability there is of a weaker link so the longer the chain the weaker it is so using that principle in reverse the smaller you make these fibers in terms of the diameter the stronger they will actually be so having these very fine fibers actually gives the high strength to the composites so composites have a lot of advantages and strength to weight they don’t usually corrode they have what’s called fatigue properties that you’ve you been something back and forth as a break and we can design them there’s one sample going around there the thin black sample if you bend it one way it bends fairly easily he bend it the other direction it’s very stiff and that’s because the carbon fibers are all running in one direction so in that direction it’s really stiff and strong you’ve been it the other way you actually can snap it very easily with your hand it’s not a big problem if you do so you can actually use that when you have an application say an airplane wing where the loads aren’t the same in all

directions you can put more fibers in one direction than the other and that will make it stronger in that direction and save weight because you haven’t put extra material in the other direction so you know 787 is a classic example these days and for commercial aircraft it’s really pretty revolutionary the size of making something out of composites is amazing that they’ve done and this is sort of showing the use of composite and this is how much composite there is by weight about fifty percent if you look at that per volume instead it’s going to about eighty percent composite because the other components are so heavy the titanium and the steel and they make it in this modular way and put it all together and here’s some other pictures showing how they actually make the nose in one piece and the fuselage in a couple different pieces and this is that same black carbon fiber we’ve been passing around and they put that together and cure it and come up with some really strong lightweight structures and here’s a picture from the testing of one of the aircraft and they’re seeing how strong the wings are and a little hard to see here’s the aircraft here are the wings all this is the huge machine they had to build around it to make to apply that much load and the wings are normally right about here you can see the wing is now bent up here 25 feet and when they let go we went right back to where it started so it’s totally what we call elastic deformation so they actually ran out of room here the machine couldn’t go up any more they couldn’t they could have gone further but the machine that didn’t have to and they’ve exceeded what they needed to for their load testing so there’s actually a YouTube video on this it’s hard to see it down here we actually watch it go up up up up up up and it’s just amazing the other applications you know is automobiles and Lamborghini has been a leader in this you know they make some really nice sports cars and they’ve come up with a new demonstrator called the I guess y esto elemento not very good at Italian but this is a mostly carbon fiber car and they’ve done a lot in reducing the weight so based on the previous version it was about 3,400 pounds they dropped it down to 2,100 2,200 pounds I mean zero to 60 2.5 seconds that’s crazy yeah I don’t know the gas mileage but it’s actually you know not just the outside of the car made out of composite looking inside of it that the whole frame is made out of composites many of the exhaust manifolds are out of composites like the wheels are made out of composite so there’s very little you know maybe I’m not sure if this part of the brake is metal maybe and the engine I mean the drive shaft is composite so they’ve really you know looked at all these different applications and actually at the University of Washington and there’s actually the lab they’re called automobile Lamborghini they used to use this part made out of aluminum and now they’ve made it out of carbon fiber composite redesigned it you know thirty percent weight loss is actually it’s quicker to make and they were able to reduce the cost which is actually kind of unique because usually composites are more expensive so we there’s manufacturing methods now coming into place that actually can make composites less expense two then metals so yeah composites are great so why am I still doing research in them well there are still some really significant challenges out there and one of them is quality insurance inspection and if you’re bonding composites together does your glue stick if somebody runs into the composite how do you fix it okay so those are significant challenges how do you make these complex structures you really don’t like to drill holes in your composites because the strength comes from the fibers if you drill a hole you’re now breaking those fibers and you’re not getting the load transfer anymore so it’s really advantageous to either bond them or glue them together or try to make as much of it you can in one piece and then you

know how do you know if there is damage they spring back so you can’t tell what happened underneath them and so we’re working out what’s called you know smart composites so these composites actually tell you what has happened to them and so looking at bonding versus bolting you know you’re going to bond it or rivet it like you do with the metal airplane you have to drill holes in it that doesn’t work very well in composites something you can do it but you’re adding metal now for the bolts that’s adding weight you’re putting holes in there so if you really can glue them together it’s much better the question is how much do you trust your glue and one of the things I study is well how do you know if your glue will stick and that requires inspection of the surface to make sure you’ve properly prepared the surface ahead of time you need to have a very clean surface about contaminants and things like that and doing that you know in a factory can be a challenge and you know can you inspect it to make sure it is clean so we look at the different bonding mechanisms it’s a chemical bond so here’s sort of a magnified view of what would be sort of the composite surface and the red would be the glue that goes in and fills in all these little micro voids you really can’t see by I and how do you do this so that’s one of my areas of research another area as well how can we make composites so we don’t have to glue them together can you come up with new ideas to manufacture them and make them into the shapes you need I do a lot of work with local companies when I’m is called envision and they’ve come up with an idea of how you can actually make these so we call integrally stiffened composite parts so it has the structure built into it and so sort of an example of what was impossible to build previously in composites looking at your aircraft door and the way they make them right now is with all these different pieces of metal or sometimes composites and they’re sealed and they’re bolted and you know looking at a cross-section through here it’s a pretty complex structure well what if you can just make that in one piece like this a composite and just making an i-beam it’s pretty easy but if you’re actually trying to do this inside here with call skins on both sides it’s really hard to get the composite to consolidate together properly so there’s this new manufacturing method where we can actually start with these plastic bottles we call them but they’re actually very precision bottles you can wrap your composite around them put them into a mold and then um we’ll sort of blow up the bottle and this presses the composites together from the inside traditional methods they use presses and things like that and squeeze them together so having these precise bottles inside then you actually can break out the bottles after you’re done can make these composite parts and here we’ve cut one open to show the structure you can make inside this would call a tool using this method and looking at that that’s sort of a test article you know we really want to make something like this so here is a we call a wing box and you know the current way as these metals parts that are all bolted and bonded together and many many different components there well if you take that design that and out of making into a carbon-fiber piece and then we actually were able to produce one of those all in one shot using this new technology so we didn’t have to do any bonding or bolting or anything like that and it came out to be actually lighter than the part and actually cheaper because the time it takes to drill all the holes and fasten them and inspect them and do all that if you can make it all in one shot it actually can reduce the cost so now moving on to sort of little more futuristic thoughts the other area is well you know what can we make a smart composite so I use the analogy of a mood ring okay so what if your car had a mood ring it’s going to tell you it’s not feeling well or you know it’s got the check engine light right now but you know what do we can take it further than that you know I’m rusting in the back corner or something like that and well some of them get two colors but we want to try to make what we call a smart composite and one of the ways we want to

do this is not put wires and sensors and things like that into the composite that’s just adding weight and complexity what we want to do is I actually do what’s called molecular engineering so you actually design your molecules that you can add into the composite that can tell you things about what’s going on there how hot it is how much stress it’s under has it been damaged has it been hit by lightning things like this so these molecules would give out a different signal once they’ve been exposed to something the trick is to get that to mix into this resin and be uniformly distributed throughout the composite so we’re working on this and so we use are called molecular sensors we design these molecules so in this case we’re looking at a stress sensitive material when these two molecules are together they might be on which would give one color and then when you actually pull them apart they separate and you can get a different signal out of them in this case it’s a fluorescence so it’s like you’re glowing that our posters and things like that okay well we’re getting the composites to glow according to how much stress they’re in and starting off here it was yellow and as we pulled on it we actually be able to get to change color so this would be it could be used to inspect for damage so if you know somebody bumped into your car or more seriously somebody put the baggage truck into the side of your airplane and it popped back out and pilot can’t see it but the guy with the special light can see it and say oh look we better take a look at this so that’s what one of the futuristic things I’m looking at working with so the big advantage of this would be one is the safety but also because they’re hard to inspect we really have a large safety factor with composites they’re over designed so they’re heavier and stronger than they really need to be so if we can understand them better by having these molecular sensors we really can push composites even further to understand the effect of aging environment damage how good a repair and having this composite that can talk back to us really would help a lot and of course all you know a lot of things start here in the high dollar world but look at the number of composites that are out there now using wind energy automobiles sporting goods medical applications so the composites really do kind of filter down into proper applications and so that just wrap up that you know I’m trying to make them stronger stiffer smarter and safer and starting off with with Leonardo’s ideas to today’s ideas and you know hopefully in the future even better ideas so thank you very much all right now the boeing company is putting these composites together into a huge fuselage but you say they’re making him in modules all right since glues the problem how are they putting those modules together and secondly is that safe it’s a good question they do make them in modules they have designed them so I don’t know all the exact design details but there they are they do use fasteners bolts and rivets to actually hold the sections together in addition to bonding them so there’s a redundant thing there and I think it’s safe and I’ll try it hi this is a very basic materials question but as someone who’s not in the field of Ellen didn’t study it I find that I have a very limited mental model of what a ceramic is and I wouldn’t have thought of glass as a ceramic so I’m going to be good kind of explain what the technical definition is of a ceramic okay there are several different you know versions and definitions of a ceramic so the ceramic is generally a covalently bonded or ionically bonded material often it’s if you look at the periodic table you can start divide it into metals and nonmetals so a ceramic is generally a metal combined with a nonmetal to make a compound so a glass is silicon dioxide so look in with two

oxygens bonded to it so silicon is sort of a metal and the oxygen is definitely a nonmetal so that’s an example of a ceramic you also like aluminum oxide this is ceramic there are also ceramics that are put together that have more covalent tight bonds so if you have silicon and carbon it can bond together and make silicon carbide and silicon and nitrogen can bond together and make silicon nitride and you can add many different mixes like oxynitride xand things like that combined with in some generally it’s a metal combined with a nonmetal with either a sharing or exchange of electrons I guess it’d be a two quick questions is there such a thing as pre-stressed composite somewhat like a preacher s concrete and second since most of the composites are essentially woven cloth layered on top of each other is there anything any work to potentially make it like a 3 direct3d ply so the first question was pre-stressed yes oftentimes it’s not intentional though pre-stress is also another we call them residual stresses so a lot of composites are processed at higher temperatures in order to get the polymer to react and form a strong polymer and so then when you cool it down things shrink differently and so you actually can get these residual stresses which can cause your composites to warp and go to shapes you don’t want them to I’m trying to think of advent of cases where this is done intentionally like it is in pre-stressed concrete to actually increase the strength of the the material and rigidity in terms of the rigidity it would most I wouldn’t see much advantage because the other rigidities due to the fibers and they’re fairly linear but in terms of increasing the strength so you could actually get compressive stresses in certain areas so cracks don’t grow I don’t know of any applications off the top of my head but I know sometimes they use composites in concrete and actually pre-stressed composite instead of steel to do it there are some examples in like Corral where which is the unbreakable ceramic plates there they basically pre-stress it by putting the surface and compression and the inside intention again by using the thermal expansion mismatch I haven’t seen too many where they actually pull on and physically and let them go though the second questions regarding this or the geometry of the reinforcements and the majority of them are you know sort of layered in one plane basically and so in the cases where you have like a hoop stress or something like that and if yousa lodge that’s great there is new technology coming out what’s called braiding so they actually do that it is having layers stacked on top of each other they actually braid the fibers into 3d structures and other times they will actually take layers of these fabric and then go through and stitch them with almost like a sewing machine so you do get fibers going in this direction as well so that will help increase the strength because if there aren’t any fibers in that direction it won’t be strong you know some of the parts going around it was not a strong in one direction and they actually snapped which is fine so to combat that they’ll click fibers you know across that direction but now if you try to pull it apart how do you get fibers going this way so it’s a it’s looking at trying to make 3d composites is a new area yes thank you I used to I’m used to motorcycle fairings where they for putting mount points for the fairings you you actually either wrap the fiberglass around it and typically put some kind of like a Lumina backing plate or something there for bonding the carbon fiber and stuff is there a way for the bonding methods do you actually

ever split the fibers like not break a fiber but put something between the fibers and make your whole there or is it wrapped around like do you actually just drill them which loses strength or do you wrap them and then bond them you know glue them after you’ve made your shape with all in it so you for putting your holes or inserts into composites it’s best if you can actually wrap the fiber around it like that but in many cases it’s too complex of apart and in a manufacturing environment they will actually just go through and drill it out and that’s sort of what you know they have to do and they sometimes will put an insert into the hole to help stop there to redistribute the stress better but that’s what they do that’s why when bonding you actually don’t drill any holes you would you know overlay them and put a layer of adhesive between them and then apply the stress in this direction it’s instead of actually you know putting holes and rivets in there with the use of composites you’re obviously saving materials just from the get-go but is recycling something that’s that’s thought of at this early in the development of composites do you think about how what you do when you’re done with these materials once they’ve they’ve reached their end of life that’s a very good question and there’s a lot of thought going into it it depends somewhat on what type of matrix you use plastics can generally divided it into two main categories ones what’s called a thermoset plastic like epoxy you heat them up and they won’t melt whereas many others are called thermoplastic polymers such as the recycling you put out in your curbside where those can be melted and they’ll actually go back in sort of a liquid form and can be reused so if you put one of those types of polymers around your fibers then you can reheat it and tentatively recycle it with the thermoset the typical epoxy and things like that that’s more of a challenge because these polymers are now permanently set in that geometry so there is a lot of work going on and trying to see well can we maybe recover the carbon fibers and give up the epoxy matrix because even making the carbon fibers is very energy and resource intensive and they’re very expensive if you could recycle the fibers maybe you wouldn’t use them in an airplane but maybe you would in a laptop case I think a few years ago high up a Boeing actually said well will this grind about put them in parking lots but that didn’t go over very well so it’s you know when you’re looking at you know fifty to a hundred dollars a pound material you want to find a way to keep the value in it so there is actually research going on and how you can perhaps recycle these at least get the fibers out or is there a way to reuse then you know other less demanding applications in your example of the baggage cart hitting the 787 if there had been enough damage that that section of the fuchsia lock fuselage needed to be replaced what happens then obviously don’t scrap the whole plane because section has been destroyed what kind of repair processes can be done on something like that it depends you know on the size and location of the damage and what is sort of behind the fuselage there what type of actual structure is there um they have been developing and they actually said you know they design for repairability that’s one of the key things because you don’t want to scrap a huge aircraft because that happens so right now the most conservative repair is actually what they call a bolted repair so they can actually reform similar parts of what was damaged behind there and bolt those on to the damaged parts and they’d be like called doublers or things like that and it would obviously increase the weight of that section but it would restore the load carrying capacity and once you do that you know reinforcing the main structure underneath fixing the skin is not as hard that’s more of a thinner layer and we you can actually grind out the damage deposit and you can get the fabric like that and put the glue and all most likely prepare a sailboat or a kayak or

something like that a little bit higher technology is used to do it and build that back up and you wouldn’t really be able to tell from the outside and it would restore the structural integrity to the aircraft as they’re using sometimes to do all composite sometimes they’re using titanium and other advanced structural materials to repair what’s needed on the inside I recently saw a talk by a couple of spacecraft historians who had been looking at the lunar landers and and one of the things that really impressed them of those craft from 40 years ago is how flimsy they were I wonder if you have any thoughts about the future of composites as it applied to spacecraft particularly if there’s any sort of potential for solving some of the human spaceflight challenges like dealing with radiation in outer space there is a lot of composites being used in spacecraft now there’s different environmental things you have to worry about such as the amount of space radiation and things that are sort of filtered out by their wrist environment but in terms of you know the weight savings they are fairly widely used and so I think they’re you know there’s a lot of good applications there for composites in space as well my dentist uses these light cured composite fillings in my teeth is it same thing that you’re talking about well again a composite is a very generic term of a mixture of two materials put together I mean concrete is actually a composite because you take rock and you take cement and you mix it together and you have a composite the kampala dental composites are not too far away except they’re not using continuous fibers so they have a polymer resin and then they have what are called the particles in there so I’m not sure if they’re ceramic particles or other polymer particles mixed together with something that will bond it together and they put it into your teeth and shine the light on it and that light causes a reaction to take place in the sort of glue that’s holding all the particles together and cause to firm up and become hard so it’s similar yes do we have any questions in the back room so I was interested in what you were saying about how the was at the Lamborghini that was had a lot of its some of its engine parts made out of the composites so how would some of those polymer composites react under higher temperatures do they stay as strong how do they compare to more traditional metallic components at high temperature the youth temperature of polymers is generally lower than that of metals so you know the actual engine itself for the Lamborghini is made out of metal but they do have you know many parts that were traditionally made out of metal sometimes the exhaust and maybe some of the valve covers and things like that made out of composites and it depends on what polymer you use to make them out of and there’s been a fair amount of advancement in getting higher temperature capabilities out of polymers so if they can use the polymer matrices and many of them have their called aramid rings sort of those six-sided carbon things if you ever saw in chemistry the more of those you can put into the the molecules generally the higher the youth temperature of the polymer will be so if you can increase the strength of the bonding between the polymer molecules you can increase their use temperature and so they are getting used temperatures and thinking for 500 degrees now so pretty significant and so they do things you know perhaps they’ll have some metal on the inside and then a polymer on the outside then is that the temperature drops say in the exhaust then go to all composite so there is some there are definitely limitations

there are also classes the composites that don’t use plastics for the matrix they actually can use a ceramic or a metal for the matrix so there metal matrix composites out there and there are ceramic matrix composites and in some aircraft they actually use these ceramic matrix composites well they have a ceramic matrix and ceramic fibers and they are actually used at higher temperatures than the metals can withstand so in metal aircraft that metal fatigue is one of the things that determines ultimately the useful life of a aircraft in a composite plane short of the engine failing what’s going to be fine the ultimately the useful life of a composite air structure aircraft structure that’s a very good question in terms of a commercial aircraft they’re not really sure yet as far as I know and there they have some their postulating I think it may just be there going to be designing better aircraft by then with better aerodynamics or you know better composites in it so they may just become just obsolete the which I think of the L what’s the Achilles heel of composites that would lead to it to degradation but they’ve been you know doing some test articles that have been flying for 20 25 years and they’ve taken them apart and looked at them and they still look good so I’m not sure what’s actually going to cause the composite aircraft I think it’s probably be that they design better ones you know after 40 years in service this give me time they’ll be a better design testing the most in composites these days in terms of government agencies or companies maybe besides bowling again you know composites is a huge area and many different types I mean aerospace is one but wind energy is becoming very large I mean composite boats have been around for quite some time so it depends how you want to measure it in terms of dollars you know aircraft still is a very high priced high end use of composites but you’re looking at you know sporting industries are really starting to use them now wind energy medical looking at trying to get other transportations getting them into automobiles we to really go to an electric car one of the big things will be is to reduce the weight so we can make a composite car that weighs half as much you’ll be able to go down much further on your battery so I really don’t have data to say who’s the biggest investing right now I mean that the government definitely is you know they always have military has always been digging composites but the consumer use of composites it’s also taken off and so I don’t have a good idea on the dollar figure it’s pretty widespread in industry they’ve been going to the direction of as opposed to solid composite material at far p to foam core ball support materials is that also the direction they’re going in aerospace in in some cases they do a lot of honeycomb structure there instead so they do a lot with aluminum honeycomb and Nomex honeycomb but the durability of a solid laminate is usually better than that of a honeycomb honeycomb there’s a lot of empty space there and you can get moisture aggression and then you get freeze thaw problems and things like that so you know the fuselage these aircraft are pretty much solid composite laminates the wing skins are fairly solid but there is work on you know coming up with better core structures so I said it’s aluminum or that it’s called nomex such as some sort of a high-temperature paper can they make a carbon fiber honeycomb now it actually is more of a structural honeycomb and has better properties so it’s an area of investigation but in terms of damage tolerance and things like that a solid lamb and it is much

more robust there’s a question about the ductility or the deformation that occurs in composites affecting the drag I’m not an aerospace guy in terms of you know looking at the drag coefficients and things like that but I think the fact that the wings are more flexible actually have let them design doing differently so there’s less drag because it can be either narrower or something like that and I think they do do a lot of modeling and actually you’ll they measure for a certain force how much will the wing deflect and things like that so I think that’s fairly well known to the aerospace designers and the composites actually can be designed stiffer than metal hi I was really interested when you mentioned that trees were composite materials um I know that’s more of a biotech question but are there people interested in growing composite materials yes there’s a lot of things that are actually composites your teeth are composite your bones are actually somewhat of a composite seashells are composites antlers are composite so there is a whole field and I’ve known as biomimetics in trying to mimic biology and you know seashells are amazing they’re creating these ceramics at room temperature in seawater with you know some proteins and is there a way that you know we can understand that and use that to create composites or both either you know regrow teeth or regrowth bone or can we understand it and actually grow technological materials using what nature does somehow at least it’s cause sometimes called templating somehow these organic proteins arrange themselves so that atoms like to sit there and they grow crystals and grow shapes and trying to understand that is definitely an area of interest and it’s probably not something we’ll see in the next two or three years but down the road trying to grow composites artificial composites is definitely an area of research

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