James Anderton: Directed-energy deposition is a great way to build very complex, sophisticated parts with complex internal geometries out of metal. I'm with Melanie Lang, she's co-founder of Formalloy. Melanie, we're standing in front of a machine here which is usable not just for making complex parts, but also maintenance, repairs or modifications. Tell me about it!
Melanie Lang: That's correct! So, we can do traditional additive manufacturing applications, building part from scratch like you said with complex geometries. We can also do repair of existing parts, or feature addition. If you had a part that had a design change, you can put the part back in our machine make the change, make the addition to it. We can also do cladding. We can add coatings to things for impact or corrosion resistance, for example.
JA: That’s an interesting point. The holy grail in many materials applications is a very tough, wear-resistant sort of outer casing, but with enough ductility that you have a reasonably soft ‘core,’ if you will. It’s the essence of heat treating and a lot of case-hardening technology. So, in this case you could actually apply a different material, a tough, hardened material over a soft core?
ML: We can do things that are called gradient materials, where you might start building with one material and then transition to another. That transition can happen quickly, or it can happen slowly, for example each layer you want to vary maybe by 10% and increase it to the secondary material in order to achieve a composition gradient across it. This part here, for example. This is inconel, finished off with a copper layer on top.
JA: Inconel, of course, is a superalloy traditionally very popular in the jet engine and aerospace industry. But you mentioned copper, and we think heat exchangers. Possible applications?
ML: Exactly. For heat exchanger components, you might want to start the build with inconel and then finish off with copper. That would allow you to take two parts that are currently separate and build them all into one single part.
JA: Using highly heat-resistant materials is one way to solve the heat problem in aerospace. Another way is to get cooling fluids around the thing. I understand you've got another sophisticated part here that shows that aspect?
ML: Right, so this is a rocket nozzle demonstrator that we made for an R&D project for NASA and it has the internal cooling channels in it. We built that in as we were doing the build. Using our 5-axis motion system, we're able to do unsupported overhangs to get the angular wall and build those channels right in, which would take a very long time and would be very difficult to do with traditional manufacturing.
JA: So, you mentioned some sophisticated alloys. What range of materials can you work with?
ML: We work with a very wide range of materials with our systems. We utilize an IR and a blue laser depending on the material that you want to work with. Everything from nickel, iron and cobalt based alloys, to hard facing materials, titanium and even coppers.
JA: And what build volume, approximately?
ML: This demo model here is about a 200-millimeter cube build volume, but our machines are customizable. We can do something smaller and we can also do much larger build volumes. This is a very scalable technology.
JA: Which industries do you expect would be the most suitable?
ML: The aerospace industry is definitely very interested in this technology, just because you can do the complex geometries like we talked about for things like heat exchangers, as well as the gradient materials. That's also of interest to the energy sector, the automotive industry, and then of course medical: we could do things eventually like titanium implants that we can induce porosity into to match that of bone density.
JA: Melanie, tell me how Formalloy started.
ML: Formalloy was founded by two engineers, myself, an aerospace engineer with a long career in the aerospace and defense industry, and also a mechanical engineer with a long history of machine design. We also had a full-time material scientist, so between the three of us we were able to concept, develop and manufacture these high-tech systems that you see.
JA: The material science is an interesting angle, because in my experience, most young companies that start machine building don't think of the materials angle. They go off-the-shelf, or they sort of improvise as they go along and iterate their way to success. So, the material science angle, is it for the material used to build the product, or the materials used to actually make parts?
ML: Both ways. More so on the R&D side to build the parts. Our material scientist helps us identify the particular applications and which alloys are going to be best for those applications. We do some custom alloy development, and then also just studying process parameters. You know with an additive process there's process parameters that have to be set for each material and geometry, and that's what our material scientist helps us do. That way, we can get fully dense parts that don't have porosity.
JA: Did you have to write your own code; did you have to write an OS basically to operate this?
ML: Yes. We have our own OS, We designed our own head, we designed our own powder feeders, we designed everything so we could optimize it for our process.
JA: That's very unusual! Normally with start-ups like this, you expect to use a lot of off-the-shelf equipment essentially and recombine them in a novel way, but in this case, you basically designed the entire machine.
ML: We did, yeah. We do use some software products and some hardware that we buy off-the-shelf, but for the most part we designed it in-house, custom, to do exactly what we want to do to optimize our process.
JA: What's the long-range goal, to be General Electric?
ML: That sounds pretty good to me!