James DeMuth is co-founder and CEO of Seurat Technologies. Seurat is a specialist in 3D metal printing, or additive manufacturing. With their own licensed laser technology, their aim is to decarbonize traditional, emissions-intensive manufacturing processes by competing with them, and ultimately, displacing them.
DeMuth spent six years at the Lawrence Livermore National Laboratory, as a Research Associate, then as a Mechanical Engineer working in Advanced Manufacturing and Fusion Energy. At LLNL, DeMuth worked on power generation, additive manufacturing technologies, and the Laser Inertial Fusion Energy (LIFE) Engine.
Michael Liebreich I want to give people an overview of additive manufacturing. Could you give us a definition, and explain why you ended up using laser-based additive at Seurat?
James DeMuth Well, you're building a part up on a layer by layer process, essentially adding a new layer of material to whatever previous layer of material you've put down. And in that way, you have the ability to have almost complete freedom over whatever the next layer is. You basically get geometrical complexity for free. Additive has been around for a long time, especially laser-based additive. Of all the techniques in metal, right, you got different types of binder jetting, you've got material jetting…A lot of sinter-based techniques, where you lay down a layer of metal powder require a subsequent sintering step. And sintering, by definition means you're not melting. You're never resetting the crystal structure of the metallurgy, so you end up having a material that doesn't have the strength that you would if you were to fully melt the material, reset the crystal structure and allow it to essentially reset itself. And so, there's only really two techniques that are out there that do that, that allow you to get the best material properties. There's directed energy deposition, which is basically think like a big robotic welder. But if you want higher resolution than you need to machine the parts afterwards, and that can be extensive, it can add a lot of time and cost. There’s only so much scalability you can get to with that process. The other way you can do full-melt additive manufacturing, is by directing an energy beam to a really small spot and get melting - local melting. Essentially, you're doing micro-welding, but you're doing it really fast, and really high precision. So, that really zeroed us in to laser powder-bed fusion of all those different types.
ML So, this is powder-bed fusion. Okay, so now tell us what your special sauce is. Talk to us about your laser.
JD So, with powder-bed fusion, you spread a really fine layer of spherical, granular material across a build-plate, and then you come back and you hit it with a laser. And essentially you're drawing your laser like you would a colouring, book filling in a colouring book with a pen. So, the industry that has been around for a long time, they have one to twelve lasers or more operating, essentially focusing a laser beam down to a point that's smaller than a human hair in diameter. But when a laser interacts with the metal powder, and it's melting it, they're trying to go as fast as possible, which means they're trying to drive the system as hard as they can in a lot of ways, which means more power, more energy, faster movement. This results in not just heating up the powder to its melting point, but heating it up to its boiling point or beyond, and boiling metal makes what looks like black soot. And so, it's this crazy dance they have to do today, where every laser produces a soot plume from the weld pool, and every laser needs to avoid the soot plume created from every other laser. It gets really, really complex, really fast. Coming out of Lawrence Livermore, our insight was, we want to have high throughput and high resolution at the same time. We were really familiar with lasers and how they scale, and as you grow lasers bigger and bigger, the economies of scale get better and better and better. So, what we do is we generate this really giant slug of laser energy - very similar lasers to what they use at the National Ignition Facility. Then we embed a high-resolution image into this beam. At Livermore, they have this device that they're using for doing dynamic beam-blocking for their high-power lasers in the National Ignition Facility. Our insight was, you have a dynamic beam blocker that's programmable, and it can handle really high power laser lights.... So, what if we were to use that to pattern lasers to do additive manufacturing? And that's exactly what we did.
ML James, this is all fascinating - I mean, I have the mechanical engineering background, so I absolutely love what you're doing, it's tremendous - but, this is a show about leadership in the age of climate change. How does this help save the planet?
JD. So, we are, effectively, electrifying manufacturing, right? We're taking a manufacturing industry that has been driven by fossil fuels forever, and we're turning into one that can be energy source agnostic, right? Most parts that are machined, you're machining 60% to 80% of your starting feedstock material away, and that's material that never need be made in the first place. Our vision is, you have a part-printing factory deployed at our customer's site, making parts on demand for customers where they're needed, when they're needed, which means great reductions in supply chain complexity; I think we've all been very painfully aware of all the issues with our supply chain over the last couple of years. This is a problem that is pervasive throughout the world, right? Getting parts from A to B, that are made half the world away - why? Let's make them locally... There's a whole list of different ways where we can impact, directly, emissions. Anything that melts has the potential to be enabled by this. You've dropped the price point of all that to something where, essentially, you're seeing pervasive use of this freedom of design; I don't think we have any concept, at all, for the explosion in applications that we would see when that happens. You can make steel, a steel structure with an embedded structure within it, lighter, stiffer than carbon fibre, but infinitely recyclable. It can have high temperature-withstanding properties, it's got all the properties of steel, but it's behaving like a different material, right? Our goal is to make hardware production as simple to do and as cheap to produce as it is to write code and software. And when you can do that, there's gonna be an explosion of capabilities.