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  • CHRIS: Hi, everyone.

  • Thanks for coming.

  • My name's Chris [? Wallen. ?] I'm an engineer here at Google

  • on the Maps team.

  • And I'm hosting today Walter Voit and Srishti Goel

  • from Adaptive 3D Technologies, and they're

  • going to give a talk about what they

  • call their extreme 3D printing.

  • So without further ado, I present Walter Voit.

  • WALTER VOIT: Thanks, Chris.

  • It's a pleasure to be back here at Google.

  • As Chris mentioned, I'm Walter Voit.

  • We founded Adaptive 3D about two years ago

  • as a spin-out from a company that I founded back

  • in grad school called Syzygy Memory Plastics.

  • In my spare time, I'm a professor at UT Dallas

  • and run a research lab that focuses in polymer chemistry,

  • in flexible electronics, in radiation processing

  • and materials, and looking at fundamental interfaces

  • of materials.

  • And in this quest to make better, stretchier,

  • lighter, stronger materials, we've

  • come up with some really neat ways

  • to be able to build them layer by layer

  • and make stronger, tougher, 3D printed parts.

  • Let's get right into it.

  • So Adaptive started in 2014.

  • Up here is our management team.

  • I'm the president for now until we

  • find sort of a seasoned management

  • team, for which we're looking.

  • Srishti, who's here, just joined the team a little while ago.

  • She got her Material Science degree at Columbia,

  • and is leading a lot of interactions with the companies

  • that we work with.

  • Dr. Lund is an organic chemist by training

  • who specializes in a lot of our new synthetic monomers.

  • Dan Patterson is our first investor.

  • He's a seasoned private equity guy back in Dallas.

  • He's bought and sold more than 30 companies since 1993

  • and does a lot in the middle market manufacturing

  • and business logistics, and I think

  • has really come in and given us a lot of experience.

  • He was a Harvard MBA guy from the late '70s.

  • And finally, Brent Duncan.

  • He was the co-founder with me of Syzygy Memory Plastics.

  • He and I were grad school buddies from Georgia Tech.

  • He was in the MBA program and I was in the PhD Program.

  • Brent also has a PhD in Material Science and Engineering

  • from Duke University, and spent some time with a nicotine

  • s startup company in the Research Triangle.

  • And then has been working with a lot of technology

  • transfer back in Dallas for the better part of the last half

  • decade.

  • So what our mission and what our job at Adaptive is,

  • is to really provide services to large companies.

  • We work primarily with large Fortune 500 companies.

  • Halliburton is our first big, big customer.

  • We've also engage a number of others.

  • And we're trying to build parts that can't be made today

  • by conventional means.

  • So let me get into what that market opportunity is.

  • In the past almost 25 years, 3D printing-- you guys

  • have probably heard it as a buzz word, as a tech word--

  • and it means a lot of different things

  • to a lot of different people.

  • You can 3D print metals, ceramics, plastics,

  • so we're a niche.

  • We're just focused on plastics, and within the area

  • of plastics, we've focused on soft, rubber-like materials,

  • and viscoelastic materials, materials

  • that have extreme toughness.

  • 3D printing has had a 25% compounding annual growth rate

  • over the last 25 years or so, and it's

  • projected to serve as a critical part of the $16 trillion

  • manufacturing economy by 2030.

  • And you have to ask why that is.

  • Well, a lot of the big companies in our space,

  • in the polymer space, 3D Systems and Stratasys

  • are two of the large players.

  • And I think a lot of market hype sort of caught

  • up and even surpassed the expec--

  • or surpassed the reality of where 3D printing was.

  • If you look at a lot of these stock prices,

  • in 2014 there were some pretty big peaks,

  • and things haven't been so rosy on the market

  • side for 3D printers.

  • And the reason is because companies

  • have been unable to 3D print high value industrial parts.

  • A lot of 3D printers and 3D printing companies,

  • we like to call the Kickstarter babies,

  • have come out with the shock and awe.

  • The hey, let's print something really quickly, or let's print

  • some really complex widgets.

  • But a lot of the back end market reporting

  • from Wohlers and from other sources

  • has identified this giant additive manufacturing market

  • as the real value add.

  • It's the idea that you can print materials.

  • That if you print this first layer, the second layer,

  • the third layer, the fourth layer,

  • they need to be as strong in this x-direction

  • or this y-direction as they are in this z-direction.

  • And a lot of parts suffer from this problem called anisotropy,

  • not the same in all directions.

  • And so with our background in understanding polymers

  • and polymer physics, we've focused

  • on printing isotropically tough parts,

  • and have found really neat ways to chemically

  • cross-link plastics in this direction,

  • as well as in this direction to make them strong and tough.

  • And in a little bit I'll show some

  • of the materials properties, some of the stress strain

  • curves.

  • I don't get too nerdy and techie,

  • but that's sort of the limiting problem that's

  • kept these kinds of materials from being

  • a solution to industrial problems.

  • Today, a lot of 3D printed parts are used to print molds,

  • to print jigs, and then you'll do conventional manufacturing

  • in those 3D printed molds.

  • But it's difficult to print a rubber, to print a plastic,

  • and have that go into an automobile,

  • have that go into an oil well, have

  • that go into a tennis shoe, have that go into a spaceship.

  • And so, what we're looking at doing

  • is solving that problem for a subset of materials.

  • So today less than 29% of 3D printed parts

  • are used for functional parts, and the market

  • is just a fraction of what it could become.

  • So what have we done over at Adaptive

  • to print these tough, high quality rubbers and plastics?

  • Well, we've focused on very scalable solutions.

  • So while we are synthetic, organic chemists at root,

  • we've tried to limit the design and manufacture of brand

  • new monomers.

  • But we use things that we can source from large chemical

  • manufacturers that can be scaled to meet a large market.

  • We've developed a very nice patent portfolio.

  • A lot of the research has been translated from research

  • at the University of Texas at Dallas.

  • But we've been able to build materials

  • with incredible strain capacity, things

  • that can stretch five times their original size

  • and then snap back into shape.

  • Or things today that have a toughness of 16 megajoules

  • per meter cubed, and some experimental materials that

  • are far greater than that.

  • And I'll get more into those details in a little bit.

  • We also tune a lot of the important properties

  • for 3D printed parts.

  • We've developed a new kind of 3D printer to make our polymers,

  • following a process called SLA or stereo lithography.

  • But we've used Texas Instruments DLP projectors.

  • You might have seen the ads, it's

  • the little mirrors, little girls with elephants running around.

  • Maybe you've got home theater projectors.

  • I don't know if this is a DLP projector, but it probably is.

  • But what we can do is we can focus light.

  • These mirrors will actuate at about 6,000 Hz,

  • and so we can turn light on and off very controllably, very

  • selectively, and we designed resins

  • that can be selectively photopolymerized.

  • And we can very rapidly print layer after layer,

  • and print a whole layer at once at the resolution

  • of SLA technology.

  • So most of these mirrors are spaced out

  • about 16 microns apart in one of the machines

  • by the time you have your throw angle down onto a part.

  • It's a little larger than that, so in x and y

  • we've got feature sizes in the 20 to 75 micron range.

  • And then in the z-axis we can make

  • that as finely resolute as we'd like, or as large as we'd like.

  • And that dictates a lot of the print speed of our parts.

  • We've come up with some really interesting

  • post-processing techniques.

  • A part of our process involved only partially

  • curing this layer, so that when the next layer comes on,

  • we get this full chemical covalent cure.

  • And so we've got some very interesting

  • post-processing steps that help solidify these properties.

  • But at the end of the day, instead of providing materials,

  • or providing printers, we're really

  • working with large companies to provide solutions

  • to underlying problems.

  • So for instance, with Halliburton, they've

  • got some needs for very specific geometries

  • in their downhole completions team.

  • So they need plastic parts that can essentially

  • help keep wells open or help close up wells.

  • We need parts that have a high strain capacity,

  • but have a high toughness, and have

  • to be in pretty complex shapes.

  • And so those are the kinds of things that we like to tackle.

  • So what we can do is we can replace polymers

  • where you'd normally use rubbers,

  • nylons, for a host of different markets

  • that you see pictured here.

  • And by controlling the monomer concentration, some

  • of the processing characteristics,

  • and a host of the additives, we've got a huge range.

  • As you can see up here in the little profile,

  • we've got a lot of different parts

  • that I'll play around with.

  • One of the things that we spend a lot of time on

  • is we play with internal structure in 3D printed parts.

  • So here you'll see six little wafers

  • of the exact same material, but the effective stiffness

  • of these materials ranges dramatically.

  • So here's something that's fairly stiff,

  • but it's also not very dense.

  • It's got near the stiffness of a solid part,

  • but because of how this lattice structure is created,

  • a lot of the stresses are translated linearly

  • through the part, and so we've got a very stiff material.

  • We've got other ones that have the exact same density,

  • but by having different internal geometries,

  • we have a huge range in the effective stiffness

  • of these parts.

  • So by being able to selectively control internal geometries

  • during this 3D printing, we can do a lot of things

  • with the same material.

  • And then by changing materials, we've

  • got a huge parameter space to play with.

  • Here's some little Androids we printed for you guys just

  • for today.

  • They also have little microchips that

  • are embedded in their heads, so you

  • can download a little TagWriter app and scan over them

  • and they'll say something fun to you guys,

  • if you want to come try it out a little bit later.

  • Here's some dragons that we've also printed.

  • And so you can get a sense of some of the feature sizes

  • that we get.

  • These belong to a class of materials

  • that we've done a lot of research

  • in the lab, which are close to materials called shape memory

  • polymers.

  • So these happen to be materials called viscoelastomers,

  • or they're materials that are in this transition state.

  • So you can see that when I deform this dragon's wings,

  • they're sort of slowly starting to recover.

  • Well what we can do and what our lab back at UT Dallas

  • focuses on, is these materials called shape memory polymers.

  • Here's a little business card made out

  • of one of the shape memory polymers.

  • But it's a material this is stiff and glassy

  • at room temperature.

  • It has a modulus of 2 gigapascals,

  • so it's just like Plexiglas.

  • Now if I heat this up in my hand,

  • and get it to room temperature-- or get it

  • from room temperature, sorry-- to body

  • temperature, what it's going to do,

  • is it's going to get orders of magnitude less stiff.

  • So what I can do is I can bend this

  • into some sort of metastable shape,

  • and then as soon as it cools off,

  • it's going to get very hard again in this new shape.

  • So a lot of plastics do this.

  • If you've ever as a kid played with liquid nitrogen,

  • you can stick a banana in it and you

  • can hammer a nail into a wall.

  • Or you can dunk a racquetball and hurl it against the wall

  • and it's going to shatter.

  • Or you could dip roses in liquid nitrogen

  • and then they just crumble apart.

  • Well we can design materials that

  • undergo that same sort of brittle to ductile transition,

  • but instead of over hundreds of degrees

  • they can do it over five degrees.

  • And so what we do is we park these materials

  • right at the onset of one of these transitions,

  • and then when that temperature increases a little bit,

  • they get really, really soft.

  • So here are two very similar materials,

  • but this is one where that glass transition temperature, as it's

  • called, is just a little bit closer to room temperature.

  • So as soon as I put this in my hand,

  • it's just going to sort of soften immediately.

  • And so it's going to go from Plexiglas to silicone rubber.

  • And I can bend it, I can manipulate it,

  • but then it holds this new shape very, very well.

  • So a lot of this engineering we've

  • done in designing these shape memory polymers

  • is similar to the problems that we

  • face in the 3D printing world.

  • What we're trying to do is engineer cross-links, engineer

  • these multimonomer solutions, engineer

  • the sterics of side chains.

  • So basically, how these little groups hanging off

  • of our main chain polymers interact with each other

  • to make things stronger, to make them stiffer,

  • to make them tougher, to make them less brittle.

  • And so a lot of that engineering has gone into the materials

  • that we've developed at Adaptive.

  • So what's the real market need?

  • This is a snapshot straight from Stratasys's website.

  • Stratasys is one of the large 3D printing plastics companies

  • in the country.

  • And you can see in the upper right

  • corner of that chart they're missing

  • a whole swathe of materials.

  • So they've got an FDM set of technologies,

  • that's on the left, that stands for fused deposition modeling.

  • That's sort of if you'd imagine taking a hot glue gun

  • and squirting it out and building a pattern,

  • and then putting another layer on, and putting

  • another layer on, you can build materials quickly.

  • Their PolyJet process lays down an unpolymerized resin

  • and follows behind with a laser, or with a UV light,

  • and sort of spot cures it.

  • So our technology is a lot more similar

  • to their PolyJet technology, where we're curing something

  • directly out of a resin.

  • And the materials properties we get

  • are up there close to nylons, close to some

  • of these very high performance materials

  • that 3D printing has had a tough time making

  • in complex, arbitrary shapes.

  • So let's get into a few more technical specifics.

  • Here's a host of non 3D printed materials

  • and what their mechanical properties look like.

  • So if you look on the left, that axis is the tensile stress.

  • That's basically how much force it takes to deform a material.

  • And it's proportional to the cross-sectional area

  • of that material.

  • PMMA is Plexiglas, that's like this material.

  • So it's a fairly strong but very brittle material.

  • If you look at something like low density polyethylene,

  • high density polyethylene, polypropylene,

  • they're materials with a lot of give, with a high strain

  • capacity, but their strength isn't quite as high.

  • And then you've got materials like PA6.

  • That's a polyamide, or a nylon base material.

  • And those combined have a really high strength

  • with high strain capacity.

  • And for us, the figure of merit--

  • and I think for a lot of 3D printers-- the figure of merit

  • should be the toughness.

  • And the toughness is the integrated area

  • underneath that stress strain curve.

  • And that explains how much energy a material can withstand

  • per cubic meter, or square meter if it's an impact

  • test, or per linear meter.

  • And so what we'd like to do is engineer materials that take up

  • as much space on this graph is possible,

  • that are a combination of being stiff and being strong,

  • but also having a high strain capacity.

  • Now the modulus-- oh, yup?

  • AUDIENCE: Is that to rupture, all those curves?

  • WALTER VOIT: These are to rupture.

  • So these are the strain to failure points.

  • And so what you see on this far end of the curve--

  • let me get a laser pointer out here

  • so people online can see me.

  • One moment.

  • Yeah, perfect.

  • So if you were to take the slope of this line in the very, very

  • leftmost region of this graph, that's

  • called the linear elastic regime.

  • And that slope is the Young's modulus.

  • And that sort of tells you-- that's effectively

  • the stiffness of the material.

  • So if we want a material that's soft and rubbery,

  • we need something with a very soft or very low

  • slope right here.

  • But something that as you strain it, it sort of strain

  • hardens and get stiffer and stiffer.

  • And by doing that, we can get a very tough material

  • that's very soft and behaves like a rubber.

  • If we want an extremely tough material

  • and we don't care what its feel is,

  • we don't care that it's soft or stiff,

  • but we just want it to absorb a lot of impact.

  • You'd like a material that's fairly stiff but not brittle,

  • and then as you get past this yield stress point,

  • you have a huge strain capacity until failure.

  • And I'll show you some of our curves in just a minute.

  • But so what we have is a couple ways now

  • to engineer the effective stiffness of a material.

  • One way is by tailoring the stress strain curve,

  • and another way is by tailoring this internal geometry.

  • And this internal geometry is not something

  • that you can do with conventional manufacturing.

  • So for instance, let's say we wanted to build

  • an insole for a running shoe.

  • A lot of that insole is actually wasted material.

  • There are certain points in that shoe

  • where stresses are transferred from your foot

  • down to the ground.

  • If we could engineer material for those parts

  • to effectively translate the stresses

  • and have everything else essentially

  • be a very low density foam, we could reduce the materials

  • costs, we could reduce the weight without any sacrifice

  • to the end strength of the material.

  • There are no conventional ways to manufacture parts like that.

  • That's why these market projections think

  • that 3D printing has such a place in manufacturing markets,

  • even though today it's more expensive than injection

  • molding, than extrusion, there are just

  • things that you simply can't do with conventional thermoplastic

  • processing means.

  • So let's look at some other parts today

  • and how 3D printed parts stack up against them.

  • So what you see in the top left here

  • are some of the world's best materials.

  • They're some of the world's best plastics.

  • These are different combinations of polyestheramides

  • that have sort of a stress of 10 to 18 MPa,

  • but have a strain capacity all the way up to 1600 or 1800,

  • so this is something you could stretch

  • to 16 times its original size and then it's

  • going to sort of snap back and not deform.

  • So these are very, very tough materials.

  • Here are some materials, some nylon based materials,

  • that when you combine them with small amounts of carbon

  • nanotubes, or single-walled nanotubes, or buckyballs,

  • or carbon fibers, you see you get

  • this big increase in their stress

  • without a large sacrifice to their strain capacity.

  • And again, these are non 3D printed parts,

  • but these are some of the engineering methods

  • that are used to increase the properties of parts.

  • So now looking down here, what you

  • can see the difference between injection

  • molded parts and then a 3D printed part.

  • So here's an injection molded part out of this material.

  • And this is a PA-12, so a nylon based material.

  • And you can see how little strain capacity you

  • have once this is 3D printed.

  • So when this is 3D printed, those layers simply

  • don't stick together well, so the neat material has

  • incredible strain capacity, the printed material is tiny.

  • Same thing over here.

  • You've got this 250% strain capacity for an injection

  • molded material.

  • You've got a 30% strain capacity for the 3D printed material.

  • The story is the same.

  • Wohlers released a market report in 2015

  • that looked at a lot of the commercial 3D printed parts,

  • and most of the strain capacities of those parts

  • were in the 10% to 30% range or lower.

  • But it was difficult to 3D print parts that were a lot stronger.

  • Google recently was part of a fund-raising round

  • for carbon 3D, which apparently they

  • haven't released too many stress strain

  • results of their materials yet, but can print fairly

  • high strain capacity materials.

  • But perhaps at very limited toughnesses and very limited

  • stresses.

  • So what are some of the innovations that allow

  • us to print these materials?

  • Well the first one is sort of a new printer

  • that we've developed that right now we're

  • calling the Z cup model.

  • But what we can do is we can package our resin

  • inside of something-- you guys maybe have used Kurig K-cups.

  • You can stick a little piece, a thing of coffee grounds

  • into a machine, you can push a button,

  • and it makes some coffee for you.

  • One of the big problems with handling resins for consumers

  • is that you have to handle those resins.

  • Often they can be noxious, they can have odors.

  • We can package our resins into these little sealed cups,

  • these guys plug in to our printers.

  • We can manipulate the height of something we've call a Z fluid,

  • which is a material that's a little bit

  • more dense than our monomer resin,

  • and then we can very rapidly print things layer by layer

  • within these Z cups.

  • So what that printing system looks like, would be you

  • can injection mold or mass manufacture a Z cup that

  • looks like this, fill it with a little bit of resin, seal it.

  • Depending on what kind of resin, you

  • may have to remove all the oxygen from the Z cup.

  • Some kinds of resins you don't have to do that.

  • And then in the machine, we can inject the Z fluid

  • and control how parts are being printed.

  • So let's get here now to some of the good stuff.

  • So here are some of the stress strain responses

  • of competitor materials.

  • And we've been able to get things

  • that have a higher stress and have a much higher elongation.

  • These are some of the parts that we're printing today,

  • we're doing some work.

  • I was at GE a couple months ago and gave a big talk on some

  • of our 3D printing there.

  • We've done some work now with the NNSA, the National Nuclear

  • Security Administration on some 3D printing,

  • and with Halliburton, and with a car parts

  • company called [INAUDIBLE].

  • They build some interesting automotive components.

  • But we've got these materials where

  • we can tune this initial modulus,

  • so we can say how we want these materials to behave

  • at room temperature.

  • But then we've got pretty nice strain capacity,

  • so these stretch to 100% up here at 15 or 20 MPa.

  • So this is a little Chinese fingertrap

  • that we built out of one of those materials.

  • As you can see, a lot of the parts that we're showing here,

  • little toys and games, a lot of our clients

  • don't like us to show exactly the parts that we're

  • printing for them.

  • But what's also really exciting is

  • some of the experimental materials

  • that we have in development.

  • And so these are materials that unfortunately

  • in a public forum like this, I can't talk at length about.

  • But I can give you a glimpse at some

  • their thermal mechanical properties.

  • So this is a material with close to a 400% strain

  • capacity, that has a stress up to about 50 MPa.

  • So this has a toughness of about 100 megajoules per meter cubed.

  • So these parts that we're printing right now daily

  • for a lot of our customers.

  • That's about a 10x improvement.

  • If you look at the 30% percent strain capacity

  • that a lot of current 3D printed parts have.

  • This is between a 4 and a 10 x improvement

  • over rubber-like and viscoelastic materials.

  • This would be another 10 x improvement over that.

  • And these are parts again that have

  • very interesting properties, but by tuning the polymer

  • chemistry, tuning how they behave

  • as a function of temperature, as a function of frequency,

  • we can do some neat things.

  • And so if you want to follow up with us,

  • we'd love to talk to you guys in more detail on the material

  • side, on the business side.

  • I'm sure she can handle a lot of that follow up.

  • I've got a couple other little side things I wanted to show,

  • some other fun projects we're working on

  • back at the University with some polymer chemists there.

  • But one of them is being able to 3D print

  • self-healing materials.

  • So we've come up with a really neat reaction.

  • This is a furan-maleimide reaction.

  • It's been known for a while, but we've

  • found ways to take advantage of this reaction

  • and functionalize even conventional materials like PLA

  • and like ABS with some of these pendant side groups.

  • And so what you can see here is a PLA blend

  • that we functionalized with these furan

  • and these maleimide reactions.

  • And they undergo a high temperature

  • reversible Diels-Alder reaction.

  • And so what we got here is a material

  • that we broke apart the first time.

  • And so that was this point up here.

  • We basically heated these up and shoved them back together.

  • We did another stress strain curve,

  • then it actually broke at a different point, which

  • we're really excited about.

  • So we were able to heal something

  • basically stronger than this point where it was before.

  • And so we think there's some really interesting

  • opportunities for taking very low cost,

  • conventional materials and finding ways

  • to post-functionalize those materials with pendent side

  • groups to give them some interesting properties

  • in materials that can be 3D printed.

  • But we think some of the real success

  • lies in the ground up engineering of systems

  • and of materials to solve these really interesting anisotropy

  • issues that we see in the market that

  • are limiting the broad adoption of 3D printed plastics.

  • So with that, I didn't prepare a whole lot of slides,

  • but wanted to leave plenty of time for discussion,

  • and sort of speculation about maybe

  • where this field is headed.

  • And wanted to get some of you guys's take and interest on why

  • you're here.

  • So thanks for your time.

  • AUDIENCE: [INAUDIBLE]

  • WALTER VOIT: So the question was whether the shape memory

  • polymers would fatigue as you're bending them over many cycles.

  • And so it's a great question.

  • There's a curve in material science called

  • an S-N curve, which is a stress plotted

  • versus the number of cycles.

  • And so if you stretch materials to their yield strength,

  • or the ultimate tensile strength,

  • and you do that repeatedly, then they

  • will fail after fewer numbers of cycles.

  • So a lot of these curves that you see here,

  • this is the failure at one cycle.

  • So what most materials do is you build in something

  • called an endurance limit, which is a safety factor that's

  • some fraction of this, and we can

  • guarantee that under this stress profile,

  • a material will never fail.

  • And so typically what you do is you

  • take some fraction of your yield strength,

  • you make it less than that, this is the linear elastic regime,

  • and then you can cycle material hundreds of millions of times

  • without any adverse effects to the network structure.

  • AUDIENCE: So you're saying even you warm it up,

  • it can become fatigued?

  • WALTER VOIT: So when you warm it up,

  • it won't fatigue unless you stretch

  • it pass this endurance limit.

  • And so we can define an endurance limit

  • based on how stiff and how stretchy each material is.

  • And you can heat it up and cool it down indefinitely.

  • That will not have an effect on things.

  • But when it's heated, as long as you don't stretch it

  • beyond a certain distance, you can keep doing that cyclically.

  • AUDIENCE: And about that self-healing material,

  • is that a one shot healing procedure,

  • or can it be repeated?

  • WALTER VOIT: This is one that can be repeated.

  • So at high temperature, this reversible Diels-Alder reaction

  • is sort of favorable.

  • So the monomers are just as favorable as a joint polymer

  • as a function of temperature.

  • So you get to the right temperature,

  • these reactions are sort of an equilibrium.

  • So you can basically make and break these bonds

  • really nicely.

  • So depending on how many of these

  • we functionalize onto our materials,

  • we can control how well they stick back together.

  • Now, if you have just a few of them,

  • then they're not going to be as strong.

  • But the material is not going to be as brittle.

  • And so there's a balance then between ultimate tensile

  • strength, strain capacity, and a lot of these pending groups.

  • And unfortunately in a big talk this, I

  • haven't gotten into a lot of the very hairy details

  • in polymer design.

  • But there are a tremendous number

  • of features of the monomers that we choose,

  • and how they interact, how they polymerize,

  • what they're starting viscosity is, what their side groups look

  • like, what the kinetics of that reaction

  • looks like, that go into the ultimate design

  • of these materials.

  • But today, I wanted to just show the properties.

  • And say maybe some of the market skeptics

  • out there, that we material scientists may

  • in the near future have a great solution

  • to help a lot of these businesses,

  • who've really thought a lot about 3D printing, but so far

  • haven't been able to print the kinds of parts

  • that their customers need.

  • AUDIENCE: You talked about the Z cup

  • for printing some of these smaller parts.

  • How do you handle printing some of the larger pieces

  • for like, oil companies?

  • WALTER VOIT: Well, the reality is that this Z cup

  • model is highly scalable.

  • So we've joked around a little bit,

  • but we could have a helicopter lowering a giant Z

  • cup into a swimming pool, and we could

  • print a canoe if we wanted to.

  • Now, I mean, that's a little bit unrealistic,

  • but as a thought experiment, there's

  • no technical limitation from keeping that from happening.

  • It's just a balance of the intensity of, in this case,

  • our light.

  • And we've played around with both ultraviolet light

  • projectors and visible light projectors.

  • And so depending on the initiators we use,

  • we've got a lot of control within our systems

  • over how they're initiated.

  • But we could do this on very large scales.

  • We've built larger Z cups, that are printing the kinds of parts

  • that our friends at Halliburton like, for instance.

  • AUDIENCE: So one of the things I've

  • noticed as a issue with 3D printing for production

  • is just the speed of printing the materials, versus injection

  • molding or forging or something like that.

  • And are you able to address that?

  • WALTER VOIT: Not as well as we would like, certainly.

  • So the question was that in 3D printing,

  • speed is often an issue, and that 3D printing can't compete

  • with injection molding, with extrusion, with maybe blister

  • packaging, and other things like that for making complex shapes.

  • And that is a true limitation for a lot of 3D printing.

  • Carbon 3D, a company that you guys have recently

  • invested into, has come up with some really elegant ways

  • to very quickly print parts.

  • But a lot of the customers that we've

  • talked to have lower volumes that don't necessarily

  • need that kind of speed.

  • For them, the driving issue really

  • is the underlying materials properties,

  • and not the print speed.

  • So, I mean, these aren't taking weeks and months to print,

  • we can print these in sort of 20 minutes to 4 or 5 hours.

  • So it's not that they take forever,

  • but it's also not that we're right now able to pull parts

  • out of a liquid resin.

  • But I think as we continue working on making these faster,

  • I think that the driving issue, for what we've

  • seen from a lot of the market reports though,

  • is not that the volumes of 3D printed parts are too low,

  • but it's that the materials properties aren't good enough.

  • And so I think we're coming at this problem

  • maybe from a different angle that Carbon 3D is,

  • is that we're really trying to focus on printing tough rubber

  • materials, printing tough viscoelastic materials.

  • And I think the speed is something

  • that can be engineered into the system,

  • whereas the underlying materials properties maybe can't be.

  • SRISHTI GOEL: Walter, can I add something

  • to this point really quick?

  • WALTER VOIT: Maybe come to the microphone.

  • SRISHTI GOEL: So, the other point

  • that in general, the benefit of 3D printing

  • that a lot of people, I think, miss when you first

  • start thinking about the subject,

  • is yes, 3D printing takes a lot of time.

  • But if you consider the amount of time

  • it takes away from things like having to redo your tooling

  • costs, to actually having all of the other changes

  • you have to make.

  • If you have one 3D printer, it can print anything from A

  • to Z, right?

  • You don't have to change your tools.

  • You don't have to change the assembly line,

  • you don't have to do-- if you have

  • to change every single part for some small specification,

  • you don't have to rechange your entire assembly line to fix

  • this one small error.

  • You can just change your SDL file,

  • and suddenly you're there, right?

  • So when it comes to time, that time efficiency

  • is spent more on actually making the part than on making

  • all of the infrastructure for making the part.

  • And that's where we see that even though 3D printing might

  • be smaller and materials might be more expensive,

  • at the end of day, you're actually getting

  • a more cost-effective solution.

  • AUDIENCE: So a quick question about,

  • I guess that you guys are making the material as well as the 3D

  • printer.

  • How about like the slicing in the software

  • that comes behind it?

  • Is that something you guys created?

  • Are you using off the shelf product?

  • Or, how do you do that?

  • WALTER VOIT: So we've done a little bit of dabbling.

  • I'm on a computer scientist by training.

  • I did my undergrad in CS and a master's

  • in Artificial Intelligence.

  • That's how I knew Chris back in the day.

  • He stayed on the dark side, I went over

  • to the light side of materials.

  • No, so we've built a few of our own systems

  • to print these materials.

  • So we've written some of our own scripts and software

  • to run the printer to do the slicing.

  • But to be honest, we would love an infrastructure

  • like you guys's behind that, instead

  • of relying on what we've sort of done with chicken

  • wire and chewing gum.

  • I think there's a lot of need for-- especially as we

  • get to some of these complex internal geometries

  • that we've passed out, there are a lot of very sophisticated

  • algorithms that can generate fractal-like patterns, that

  • can generate complex internal geometries, that can map,

  • let's say, a finite element model

  • that you've generated in Abacus, into a structure

  • that once you've 3D printed it, you can localize the stresses

  • and strains appropriately.

  • I think that's a huge area where software companies have

  • room to play.

  • I know that HP has recently made some acquisitions in that area.

  • AUDIENCE: What's the cost of the resin itself?

  • What's the difference between just traditional nylon,

  • between [INAUDIBLE] similar properties as injected?

  • WALTER VOIT: These are resins that are not quite as commodity

  • as something like polyethylene or polypropylene.

  • But they are not far if you look at petrochemical distillation,

  • they're not far from crude oil down the distillation pathway.

  • So if there were a need to mass-produce

  • these kinds of materials, it would

  • be very inexpensive to do so.

  • Because the volumes aren't as high now as they could be,

  • they are a little bit more specialty resins.

  • They're a little bit more expensive

  • than traditional injection molded parts.

  • But we look at what other 3D printing companies are

  • charging, following the razor blade model of essentially

  • giving away printers and then charging a lot for resins,

  • and at the lab prices that we're making resins now,

  • we are more than competitive at those price points.

  • AUDIENCE: Just a couple quick things.

  • First you mentioned being able to vary the Z height.

  • How far can you vary that?

  • WALTER VOIT: What's really neat is

  • we can do that during a print.

  • So if we had some components that structurally we

  • wanted to print some layers very quickly

  • and we want a lot more resolution in another layers,

  • we could do that.

  • It's a balance of what kind of initiator

  • we have in the material, what kind of inhibitor

  • we have in the material, what the height is,

  • what the intensity of the light is,

  • and how these little micromeres are turning on and off.

  • So a lot of projection technology

  • has advanced algorithms that make the edges, for instance,

  • look sharper and pixels.

  • So the mirrors are turning on and off much

  • faster than the human eye can see to give you

  • some interesting edge effects.

  • So there's some interesting ways we

  • can play with that combination of inhibitor, of initiator,

  • of layer thickness, and of software to control that.

  • So one thing that limits how thin we can do that,

  • is the viscosity of our underlying resin.

  • And so different resins that have different properties

  • have different viscosities.

  • In the lab, though, we've been able to spin

  • individual layers that are less than a micron thick.

  • In fact, we've been able to spin down

  • some of these kinds of materials--

  • now this is a solvent-based approach where we have to let

  • some solvent then evaporate.

  • But we've been able to build 20 nanometer thick, very

  • uniform films, and do some neat things with those.

  • Now, that's not really realistic to print large area 3D printed

  • parts, but for some of the photolithographic processing

  • we do, for instance, for building microelectronics,

  • often we need a 20 nanometer thick dielectric

  • to do something.

  • And so we've got some abilities to spin these materials down

  • to those thicknesses.

  • In terms of the thickest, it depends again on the inhibitor.

  • If you start to vary the thickness

  • within a print a whole lot, it becomes

  • difficult to balance the inhibitor.

  • Because as light is going through this material,

  • as a reaction is propagating, you

  • don't want that reaction to propagate and turn

  • your whole resin into a big ball of goo.

  • So we need ways to start that reaction

  • and stop that reaction.

  • And Carbon 3D has their own way to do that.

  • We have a very different way to do

  • that, which gives us a lot more control over how to start

  • and stop these reaction.

  • AUDIENCE: So what you do with the leftover resin in the K-cup

  • model?

  • Because it seems that you have a fixed amount of resin

  • for any K-cup and so is it just because every single one

  • is going to be custom designed for the part that's being made?

  • WALTER VOIT: Yes.

  • So for high-volume manufacturing,

  • companies would be able to specify exactly how much resin

  • they would need.

  • And we would have very little waste at the end of the day.

  • In these cases, we pushed the Z fluid up higher,

  • and then we polymerize a little A3DT disk

  • at the top that's a little knickknack that we

  • can play around with and hand out as swag.

  • In the future for highly customized parts,

  • that would be nearly eliminated for more

  • of the maker community.

  • There would be different SKUs you

  • could buy for different size resins,

  • and then it would be up to individuals

  • to determine what to do with the extra.

  • But in most cases, you would push it to the top

  • and then just finish polymerizing it.

  • SRISHTI GOEL: So the other thing is

  • we're actually, because of this problem of having waste resin,

  • we're doing a lot of studies now that are internally focused

  • on what kind of-- what quality of print

  • do we get if we reuse our old resin.

  • And so we're seeing that actually

  • if you use-- if you need something that's low quality,

  • if you're not super concerned about what kind of properties

  • you're going to get on the end user,

  • then you can actually reuse the resin and it works pretty well.

  • So we're actually working on making that less of a waste

  • situation, more of a recyclable, more sustainable solution

  • for having to deal with that kind of thing.

  • WALTER VOIT: So the question was whether we

  • were focused in medical markets, because it seems

  • like this control of stiffness and internal geometry

  • and materials properties would lend themselves well to that.

  • That's something that, with my other hat on for a moment,

  • back at the University that we're spending

  • a good deal of time on.

  • We have a DARPA grant that is focused on 3D printing

  • some artificial tracheas with colleagues at UT Southwestern.

  • My wife is actually here sitting in the back.

  • She's an ear, nose, and throat, head and neck surgeon

  • at UT Southwestern.

  • And so we're working with her and with some of her bosses

  • to do that.

  • But in terms of market adoption for a small company,

  • you can live off of grant funding and things

  • for a long time.

  • But in terms of readiness to market,

  • there are quite a few barriers to entry,

  • and we've focused a lot of our immediate concentration

  • on these near-term, high-value industrial markets.

  • And I think there's a huge segment for medical research.

  • But that will come.

  • As a company is adaptive, we've focused squarely

  • on the non-medical space so far.

  • But I think we'll continue to build

  • an IP portfolio that may lend itself

  • to that in the near future.

  • Thanks a lot for your time.

CHRIS: Hi, everyone.

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Walter Voit:"極速3D打印:以材料為中心的方法在谷歌的演講:"注重材料的方法 (Walter Voit: "Extreme-3D Printing: A materials focused approach" | Talks at Google)

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    richardwang 發佈於 2021 年 01 月 14 日
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