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hello and welcome to technically speaking my scientists and Engineers come together to try to ask common interests share knowledge and satisfy some curiosity I'm Laura and I'm joined by Jasmine and Emma to talk about Material Science what it is and why it's useful for everyday life we're also joined by an audience from the engineering development trust's roots to stem program which I think is fantastic so to get the conversation going Jasmine what is your interest in Material
Science so I'm an engineer by background a chemical engineer to be specific but it wasn't until my first year at Uni and literally my first day in freshers week I've learned about Material Science because there was a actually there was two girls on my floor who were both doing it and up until that point I'd never heard of it but like I find it really interesting because it's all about studying the different properties of materials and like even developing new materials so for me it's quite
fascinating yeah I Echo your comment about not really knowing about it until you're at University I think I made it all the way through my undergraduate three years in a career a PhD and was into a research fellowship at the University of Manchester before I really realized that Material Science was something you could study I could have studied it 10 years before that now I'm aware of it and I've been to conferences about it I feel like I've learned so much I understand much better how it
improves life Emma would you say something similar or have you got a different take on this I would say something really Sim similar as well I think especially at GCSE and a level there is no Material Science she says there is no Material Science available there's chemistry biology and physics and so I kind of thought that science was really binary in that sense and um you know you had each topic of science fit into one of those three I came to University and first I actually just met
people who it was like a meeting people what degrees are you guys doing and they would say Material Science and I was like I didn't even know that I was a degree because I'm doing it I'm I'm doing physics so I'm still in that binary but then as I did more modules and even just learned more about the different research happening at the University I just learned Material Science it's actually also in physics just as it's in chemistry and across the sciences and so it's this really nice
kind of mesh of um all of the different sites that you knew and so I've done modules just in Material Science even though I'm on a Physics degree and so I think I've just naturally learned more through completing my degree but also through just knowing people people and speaking to people about it and learning that it's this kind of umbrella term for all the different scientists that is involved that's great that you managed to do something about Material Science in a
Physics degree I think they're becoming more interdisciplinary now so even though you went to University to study one thing you get to learn about broader stuff I mean I did Natural Sciences because I couldn't decide and I think it's it's quite important that I've been able to move around quite a lot because I've had that mindset and I think because you've seen more than just like pure physics things you've also got that ability to move around yeah definitely
it's really nice as well because it also feels like sometimes you're just studying something different and after just doing three years of essential like just a Physics degree it's nice to have differences in there and explore different things in that degree um like loads of different maths as well but also biophysics and things like that it's really nice to have a break sometimes from the heavy heavy things and do the latest stuff which apparently is Material Science so is there anything
in particular that you discussed in your undergrad degree that you think is really relevant it's like any particular material because I'm studying at the University of Manchester there is a lot of focus at the University I'm sure you'll know on um on graphene because it won the Nobel Prize in 2010 which is really really cool that you know the university that I'm studying at has Nobel Prize laureates just walking around I think because of that it gets put into the spec a lot and so we
started learning about graphene in my second year and I've just done like a more advanced course in my fourth year on graphene and on like different material properties and so I think um because the university has a history of that material they want people to know about it and do like labs in it which is which is really cool yeah I was doing my PhD when it when they announced that it isolated and they won the Nobel Prize and everyone was writing around proposals that involved it and honestly
he got a little bit Fed Up of hearing about it if you weren't working with it we do still hear about it sometimes I'll just be doing my work for my week and then I'll just see graphene come up again yeah it's one of those sort of Wonder materials I guess you'll explain more about that as we go along and Jasmine you said you do things in sustainability and I think you you do things related to uh greenhouse gas emissions as well so are there any materials related to that that you think
could be relevant to this uh conversation yeah definitely it's like Steel's a really important one so still gets used in a lot of things it's used to make Cutlery cars it's used in buildings so it's a material that's used a lot but in terms of global greenhouse gas emissions steel accounts around eight percent of total greenhouse gas emissions so it's like one material that counts for like a quite a bit of global of global warming right now yeah and it's come up quite a lot in the
episodes we've done with our friendly civil engineer so we've talked about building bridges and it was really important to building skyscrapers because it suddenly became a material that could be quite easily produced in the Second Industrial Revolution we don't even tend to think of an industrial revolution it sounds like they're being full it's I found out I was researching for the previous episode so there was a chemical engineering process I guess that was
developed it became widespread in the 1870s which helped contribute to this sudden increase in growth all these really tall buildings shooting up yeah it's really fascinating because like steel it has like certain properties that makes it less suitable for making really tall buildings because it's strong but it's also full like it's weight and size it's quite light and also like you can pretty much turn into whatever shape you want yeah I know they're really different types of Steel
like in general there's four kinds of Steels so stainless steel is the one that most people would have probably have touched and used because it's what gets used to make knives and forks carbon Steels what tends to get used more in buildings and tools steel is what they use to make like tool bits it's the main reason why it's really difficult to recycle steel right now is because there's like different Grays of Steel because you have different impurities in them to make them
different characteristics when you recycle Steelix usually has a lower quality than if you were to make it from like virgin iron so that's why recycling steel right now isn't a really big thing industrially you have all these different kinds of Steel and you can't mix them all together so you would initially think that it would be quite easy because you just refer to it as steel and it's already been through that refinement process yeah even like within the four kinds of Steels there's like
even more like subtypes depending on like what you put in it the main difference between stainless steel and carbon steel is I believe stainless steel has chromium in it yeah because stainless steel has to be like oxidation resistant so it doesn't rust and stuff for that reason you wouldn't mix carbon steel with stainless steel when you're recycling you wouldn't really get either in the end you get some kind of hybrid carbon is a really important thing isn't it because it helps improve strength
yeah but then if you put too much in it makes it more brittle so yeah there are tolerances yeah it's the carbon that is the key thing to add to the iron and then you add things like chromium silicon other things to give it slightly different properties like that corrosion yeah yeah so the idea is um you're engineering the steel to have these like specific properties for different uses in industry but then also like you said just like knives and forks you mentioned
carbon steel that's essentially iron with a little bit of carbon in there yeah and that's like the basis but they both come out of the ground and they're full of impurities iron ore yeah and carbon is usually in the form of coal yeah I usually call or like Coke yes you take the car out the ground and you Coke it in a process I'm not entirely sure what that does actually I feel like I should know this yeah treating the process behind that it's kind of there's
like a sort of complicated thing about what that caulking cold does isn't this so it sort of um does it reduce the iron gets rid of those impurities in this this process that was developed in the 1870s and also you burn it to heat the um the components up so that you can form a homogeneous steel is that right yeah it's roughly right so like basically you need a carbon sauce but you also need the heat melting point of Iron and Steel is pretty high so like right now a lot of Steel is made using
fossil fuels mostly with coal just because of costs but in some places they use natural gas but they are looking to make different Technologies or different processes that will basically kind try to cut out the use of fossil fuels so that steel can essentially be decarbonized the steel sector like other sectors in the UK and the world like they have Ambitions to be Net Zero by
2050. so when you're talking about decarbonization that's about not releasing greenhouse gas emissions into the atmosphere it's not about not putting carbon in steel yeah so when we talk about decarbonizing steel production we're looking at what ways can we cut out fossil fuel use or what alternative carbon sources can we use or we can basically use different processes there's an electric version electrical alternative to like traditional Blast Furnace technology electric Arc furnace
kind of really need more recycled steel for that one to work you can also use things like biomethane instead of like natural gas and also like biomass as different sources of carbon so that would also put the carbon in the steel to give it the right strength but just be carbon from a different source and do you know how developed those Technologies are because there's obviously those plans to um open a new deep underground coal mine it's actually near my house yeah and it's really
controversial because it's about digging up fossil fuels but yeah it's also going into the steel and you can't really make this deal without it definitely it's a blast furnace that's the most mature like the alternative Technologies they do exist but they're just either much smaller scale or still in like trial stages there's going to be like a really big increase in new technologies being used just because people want basically lower car well I say lower carbon but
like steel with a lower carbon footprint essentially terminal that she's gonna get quite easy yeah I know it's going to get really confusing in this episode because uh graphene is also carbon yeah so we I think we've talked around these big engineering processes and I guess the process of making steel it's chemical engineering process right kind of we said we were sort of interested in talking about materials and yeah I guess most people think of material as like
fabric my PhD was in simulating Athens and how they interact with um other atoms and that to me is what material science is about it's about how the atoms bond together to give a solid thing particular properties like how strong is it how bendy is it so I see you both nodding so I'm gonna if you if you agree with my definition of Material Science yeah I agree I mean I don't I'm not I don't work in Material Science but like that sounds about right to me yeah as well with like especially with how
like the structure gives you different properties that's what I would classes Material Science from like a physicist and maybe I've got it all wrong so material scientists will throw around terms like um grain size in crystal lattice it's kind of odd to think about the fact that steel is crystals yeah it's little tiny crystals that have all sort of formed together and you tend to think of crystals as being shiny things like diamond another form of carbon I always think of Steel on a very kind of
macroscopic scale like I can touch steel and I've seen it that I always imagine like huge like steel like infrastructures but the only like Material Science I've really done has been very my and like on the small scale I mentioned graphene before one of the really cool things about graphene is that it's a 2d material it's not even three-dimensional you can have layers of graphene that builds up into graphite gender pencil is made of graphite uh when you're like moving your your pencil
across the paper the individual layers actually like slide off because the bonding between them is weak and that's how you get the transfer of the pencil and then that 2D material is graphene it's just this one layer structure I think it's really like important to compare with probably what you guys already know which is diamonds Diamond is made entirely of carbon and because of the electrons that are around the carbon atom uh when they bond with four other carbon atoms you get this strong
3D structure which is your diamond and in graphene those carbons only bond with three other carbons and so you have this spare carbon that's unbonded and this this leads to really cool properties in graphene one that it's two-dimensional another one is that you can form weak bonds between these layers and then you get graphite but also this free unbonded Carbon gives it some electronic properties because diamonds don't conduct but uh graphene does the bonds
that they form are very very strong so I was actually looking into it and found a stack graphene is 100 times stronger than steel what steel though did not say but I thought that was interesting because it's the classic analogy of um ants being one of the strongest creatures because they can carry so much more times their body weight but ants themselves are not strong and so I think that's the case of graphene it's very very strong but you can't make a macroscopic thing you have a 2d material
so um a lot of people use graphene in composite materials and like putting graphene into different things to make it lighter make it stronger use its electronic properties and then that's really interesting in how you bring this macroscopic thing that I can only imagine into actual real life products um such as like tires or phone screens apparently they can they have really nice Optical properties that means that phone screens can be more sensitive and clear when you said that there's a
carbon at them that isn't bonded to something with my background in simulating atoms I would say well surely it wants to be bonded to something because that would be um a lower energy State I guess is the the proper term it'd be more thermodynamically favorable let's throw another random term in there so essentially it wants to be honored for things and it's not what's stopping it I don't want to go too technical but it's um because of the energy levels that you have they can there's a word
called hybridize so form uh into different numbers and it's just um the most favorable sometimes is to hybridize into three and so you can form into those three and then they're the lower energy levels but sometimes it's more favorable to hybridize into four and then they become the lower ones okay so then to go from three to four you'd have to give it a bit more energy to get it into that different formation I think so but I also I'm not even sure if you could change it from three to four
because I think if you gave it more energy like the final the final uh the unbonded one likes to bond with other unbonded ones and that's like in the electrostatic force but it's not the covalent sharing of electrons so I don't know if it's like a tendency of different carbon atoms to rather form these three or rather form these four that like makes those happen but I think it's something like that graphene is a weird material it seems to be able to do so many things
though like Emma mentioned putting it in I think it's a car tires didn't you so I'm pretty sure that um there's a shoe manufacturer that makes trainers with it in the souls as well then I always assume that is to give it really good grip but also really good strength because normally it's a compromise so I do a lot of running so I've got like Road trainers and fell running shoes and all sorts different types of shoes with different types of running and that's to
do with the different compounds in the rubber to an extent so I assume this graphene trainer can do all of these things so I don't need five different sets of trainers I think I also saw it's been used in like tennis rackets and things but I imagine because it's so light and strong it's it's kind of like for durability but also I guess the lighter the tennis racket is the faster you can move it so the better the tennis racket acts but I think durability might
be one of the reasons why it starts to like pop in everywhere because if you're like if I just throw some graphene in see what happens test the properties of the shoe and you might get a better more durable shoe with like a lighter weight and I also saw that um it can like make fuel last longer in certain aircraft there was a term that got through about the graphene is like a green material and I don't know if it's just in the production of it or the fact that it
allows like if it makes something more durable like trainers you're going to purchase trainers less often and so it makes it more green in that sense because you're having like things that last longer and you can use things more and if your fuel lasts longer then you need less to go to the same distance and so it's more green in that sense so I'm not sure if it's like a knock-on effect or if it's actually just better for the environment to produce no it's definitely it's definitely a knock-on
effect right now graphene's not really being mass produced at least I couldn't find evidence because it's a 2d material it's actually really difficult to manufacture the two main ways of producing graphene are the sticky tape method which is also known as mechanical exfoliation where basically you get some sticky tape he stick it on some graphite you remove the sticky tape you've got multiple layers of graphene but then you use more sticky tape to basically separate out the layers and basically
the thinner you want it or those few layers you want like the more sticky tape you need but like that's not a very effective method so the other method is basically plasma enhanced chem chemical vapor deposition I'm not sure the best way to describe plasma an ionized gas and basically you just like have laser graphene deposited on a substrate of copper or nickel and that allows you to make really big sheets of graphene because plasma is an ionized gas it's really energy intensive to make so it's
definitely just a knock-on effect because it makes stuff more moderable but maybe in the future so it's like been what 13 ish going on 13 years since we've figured out how to create it I guess so there's still lots of room for like improvements because we've had steel for technically thousands of years I'm Mass producing it for hundreds of years Steels less than one percent of the mass is usually what has carbon in it so it's not a lot of carbon you're putting into that iron to give it
favorable properties no so I wonder if it's similar with um the grippy rubber that Emma talked about on any other usage you don't really need a lot of graphene in there to make a big difference I feel like it is probably the case that even just the slight differences in the compositions make a huge difference in your final properties it's kind of the same for steel so you've got composition play days apart and then you've also got how you heat it up and how you cool it down so you'll
get different shapes of crystals forming in different sizes of crystals what a grain is it's a crystal depending on what you put in there and how you treated it that is not what I thought Material Science was I just think bonds and then I just don't think about anything else like the production process completely new to me yeah it's part of it I guess how do you know what you want to make like a chicken egg sort of thing I want to make this thing how am I going to make it or what are the
final bonds that I need to have yeah and I mean a lot of Material Science is um looking at Crystals you tend to put x-rays through them to create a fraction pattern that pattern tells you something about how the atoms are arranged but I mean you also mentioned electronic properties and that's really important for things like solar panels can you explain more about the electronic side of it yeah um I found a stat that it was 60 more conductive than copper and
obviously copper is like the choice to use in wires and different electronic circuits the electronic properties comes from this carbon that's not bonded so you have this free electron it's free to move about and a charge moving is current and so you get these kind of cool electronic properties that arise from this free electron this is really important in computer-like components anything you need to run on a computer you need like a lot of transistors and
the more that you can fit onto this chip the faster things are the more memory you can store it's kind of this like amazing circuit component that just can do all of these incredible things apparently and um when you use graphene to make these computer chips you can make these transistors smaller so you can fit more on everybody wants things to be smaller and more efficient actually one of my lecturers today was talking about how uh his first laptop when he bought it was a
thousand pounds then and it had one kilobyte of memory and he was like that was that was insane that was insane about a memory and now um I think I don't know even just like a photo on your phone must be something similar to that the advancing of of that is because of transistors and like different circuit components getting more efficient yeah and that technique that Jasmine mentioned that can be used to make graphene that vapor deposition method I think that is how a lot of
electronic components you use some components have got like a layer of silicon or something and then a layer of something else on top and it's all just like individual layers of atoms built up yeah I think it's what you use when you need like really thin but precise layers yeah and then you get down this whole Material Science thing of how good is that crystal lattice that you've just made from building up all those layers are there any atoms that are out of
place and what effect does that have do you get like electrical current leaking out of your device because those atoms aren't aligned properly I think in some cases though when things aren't align properly Better Properties it's called doping in semiconductors isn't that just like moving things about and then it changes the properties to be better for certain things yes that's how they make solar panels isn't it they start off with really pure silicon and then they
dope some of it with one particular optimal ion and they dope some of it with another iron and that makes electrons flow from one of those doped things to another of those dope things that was not a great explanation we didn't do enough of them this a while ago as well so that's a bit of explanation in there and there seems to be a real drive to create as you said more efficient Electronics like more efficient solar panels certainly and that's all about what items you put in
there I think a lot of energy and effort for the research has been how can we use this material to advance this area and then this material to advance another area for example like steel is is an old material but it doesn't mean that it's worse than graphene because it's old and it's always been used it just has different uses I get to in interview people as part of my job about their research and I've spoken to so many material scientists doing so many interesting things and an awful lot of
them say that it involves all these different disciplines like you know physicists I interviewed someone recently who's developed a material that can be used in robots and it heals itself and it knows when it's been damaged as well the robot can modify its movements accordingly because it's sensed this signal of damage and it can allow itself time to heal and it can carry on and that's another aspect of Material Science I should say that that involves a polymer which isn't a crystal
no it's not some chemistry goes on there for it to heal it astones me how many of them say that it was this multi-disciplinary team of all these people there was a material that we talk about spin States I think it was about computer processes and computer memory someone in their team would essentially set up the experiment wrong and when they looked into it it turned out they discovered uh something that no one thought was really possible and it was a more efficient way of
making computer memory work based on this Crystal they were using yeah there's a lot of cool things about crystals and spin States and the way they like Orient themselves in the crystal can change things it always reminds me of how like magnets work and how you just get alignment of things in a certain direction and then immediately it just becomes magnetic and then you take away this is like an electromagnet you take away like a source of electric field that's aligning these different
magnetic moments they're called but imagine like a loads of arrows pointing in different directions and then you you apply an electric field and then all of a sudden they just all point in the same direction and then your material becomes magnetic kind of looking up for my report like how could I describe spin State and I decided because it seems like this really sort of abstract property of it's about electrons isn't it yeah there's three oh I've learned about three main spin State
models of lattices and I'm like is there are any of them even right because they're all like getting more complex but I feel like even I don't know the full picture of what the spin State even with like this approximation and then this slightly different approximation and then this slightly different approximation that's very hard and no one ever uses so you just only ever use this simple one and so I feel like nobody really even knows what the final what the actual structure is like
because it's just all these approximations which is physics if anyone wants to do physics for you that's what it is it's approximations it's not really understanding the world but it's getting close everything is an oscillator everything's upon he's an oscillator everything's awesome everything's a spring actually I should say yeah that is pretty much what I learned from when I was doing my atoms atomistic modeling sounds odd doesn't it I think we've got atoms connected by
Springs yeah do you want to go into physics pay close attention to the springs they don't go away I like how we started off talking about we're going to talk about Material Science we're going to start off with the second individual Revolution and now we're talking about weird things to do with fizzy for me Material Science is really important because you can see how these things affect your everyday life if you really think about it so thinking about you know the transistors that Emma's
mentioned that that makes smartphones possible now I remember carrying around a smartphone it's about the size of a brick it was it wasn't even a smartphone you could call people on it and that was it and now you've got the like the internet in your hand because of Material Science who knows what we'll have in a few more years that is a good point to leave on so if you've enjoyed listening to this episode you can find us on Twitter and we would absolutely love it if you would say hi to us there
thanks for listening and we'll see you next time the views expressed in this podcast belong entirely to the person that said them they do not represent any industry or organization if you enjoyed listening to these views it would really help us out if you could rate US leave a review and tell a friend this podcast was sponsored by no one but if you're interested in funding us to continue to have Frank discussions about science and engineering please get in touch [Music]