In this episode of CW Trending, editor-in-chief Jeff Sloan talks with thermoplastic composites experts from Solvay Composite Materials (Alpharetta, Ga., U.S.) about the state of thermoplastic composite materials today, and what we can expect from them in the next few years.

Transcript

Jeff Sloan 

Hi everyone, and welcome to CW Trending, CompositesWorld’s video podcast. We’re going to talk about thermoplastics and thermoplastic composites today. I have three guests, and they're all from Solvay. So, before we get started, I'm just going to ask our guests to introduce themselves. Let’s go ahead and start with you, Trevor.

Trevor McCrea

I’m Trevor McCrea. I’m a North America application development manager for thermoplastic carbon fiber- and glass fiber-reinforced composites. I originally started at Boeing for 21 years and then on to a supplier. And now I’m happy to be continuing with materials use at Solvay.

Jeff Sloan 

Great. And you have some great parts behind you there. Maybe we can talk about those? Johannes Treiber, why don't you introduce yourself?

Johannes Treiber

Yeah, hello, Johannes Treiber. I'm currently a thermoplastics application engineering manager in Europe coordinating reading this on thermoplastic composite platform in Solvay. First of all, engagement with the customers but also the technology roadmap development together with our application center. We have a materials science application center in Brussels, and then coordinate their activities with stakeholders, external technology suppliers and customers. I come originally from [an] aerospace engineering [background] and then for many years in automation of composites, which means fiber placement. Four or five years ago, I joined Solvay with some years in thermosets, and now really, since 2019, [have been] working on thermoplastic composites on our team.

Jeff Sloan 

Great, thank you. And Jim, why don’t you introduce yourself?

Jim Pratte

I’m Jim Pratte. I’m a senior tech fellow in the thermoplastic composite platform and lead scientist for product development. I’ve been working on thermoplastic composites since 1985. So, I’m sort of the old man of the group and one with a lot of histories and stories. [It’s] certainly great to be a part of this today.

Jeff Sloan 

That’s great. So these materials are not new to you, so that’s interesting. All right, I’d like to set a baseline here and just find out for our audience, explain briefly the thermoplastic products that Solvay offers to the market and which resin types are offered in which formats, I think just to give us a basic understanding of what kind of materials we’re talking about today.

Jim Pratte

Today, Solvay primarily supplies, the bulk of it is unidirectional tape with a few select fabric product forms for a few customers. The resin systems that we’ve identified and have initially gone out commercial with are PPA, PVDF, PPS, PEEK, PEKK and PEI. And again, all these can be provided in unidirectional type form with both carbon [fiber] and glass for the exception of PVDF which is only offered in in carbon [fiber].

Jeff Sloan 

And what is the maximum width of these tapes?

Jim Pratte

Today the maximum width for the APC product line, which is the PEEK, the PEKK and PEI, is 12 inches wide or 305 millimeters wide. For the other products, which is going to be the PVDF the PPS and the PPA, we recently announced a capacity increase of putting a plant in Piedmont, and so the tapes for those will eventually be 24 inches wide.

Jeff Sloan 

Okay.

Jim Pratte

Today, presently, there they're six inches.

Jeff Sloan 

Okay.

Jeff Sloan 

And there are lots of ways to apply thermoplastics to UD tapes. Can you walk us through the technologies that Solvay uses to do that?

Jim Pratte

We have two basic impregnation processes. As I mentioned, we have our APC product line which has been around since the 1980s. It is a hot melt process. It has some very unique characteristics with the tape that some of our customers, or a lot of our customers, are actually taking advantage of it for stamp forming and press forming. And then the other one is the aqueous slurry process, but that will be with [the] Evolite materials.

Jeff Sloan 

In which end markets is Solvay targeting its thermoplastics right now? Where do you see the greatest opportunity? Where's the activity?

Jim Pratte

Well, there's three basic core markets, but as we continue to work that may expand. The three core markets are aerospace and defense, and that includes urban air mobility, where there is a lot of activity ongoing in that market space. There is the automotive sector. And then finally, what we call the energy transition markets, which also has a lot of activity going into it, you have activity going into hydrogen, so tankage, certainly in the oil and gas market, there's piping ongoing and other applications in that market segment. So, I would say we have quite a bit of interest in each one of those segments. And as I mentioned, as time goes on, we're beginning to get inquiries for applications outside those three core markets, and we will evaluate whether we have the right product forms and products to be able to be successful with us.

Jeff Sloan 

So you feel pretty optimistic about thermoplastics use in pressure vessels for hydrogen storage?

Jim Pratte

Well, I think we're at the very beginning. And so it, we think we have an approach and some products that could fit that market. And so we're a little bit optimistic at this point. But we're at the very beginning.

Jeff Sloan 

Yeah, it's definitely a young market and very exciting. You mentioned automotive, and I guess that could lead to my next question. I wanted to talk about overmolding. You know, for the purposes of our discussion here, how would you or Solvay define overmolding? You consider that injection molding on around a continuous preform? Or how do you define that, just to give us some parameters?

Johannes Treiber

I can cover that one. It's a very good question actually, one very had to learn ourselves internally first, having a common understanding and common knowledge. First of all, we have the special polymers colleagues coming from an injection molding perspective. From a global market perspective for Solvay, it seen as overmolding plastic onto anything, but in the thermoplastic composites platform on this side, on the composites perspective, we definitely define it as structural overmolding, a structural combination that means really injection molding with full interface healing and full interface structural performance. And then onto both continuous composites, but also long fiber composites. So LFT products can be also an insert which can be overmolded and functionalized with short fiber molding compounds. But yeah, then again, there is ambiguity in terms of markets. If you take the classic composite markets, aerospace, urban air mobility, then you have the classic functionalization, that means taking a compound injection overmolded just by functionalizing a classic composite structure, but then automotive, as you mentioned, we really come more from the classic injection molding side and overmolding is seen as local reinforcement, local improvement with composites. And the difference there's really then the highly functionalized, the highly directional use of composites with [a] very wide range of product forms very wide possibilities from stock shapes to blanks, so not the classical aerocomposites. And that makes it not very easy, not very straightforward to say, what's overmolding. We see this by market, by technological approach and from which direction you take it.

Jeff Sloan 

Is there an end market in particular that you feel like is strong there? Is there a particular market that shows great promise there?

Johannes Treiber

Trevor, do you want to perhaps steal this one too?

Trevor McCrea

Well, I was just going to say and reiterate, you know, classical, when we say overmolding, it's as if there's a composite there, and then we're injection overmolding onto the composite, which is kind of the classical way to look at it. But as Johannes was saying, you know, when you get into automotive, they're very familiar with injection molding, and it's as if the tape is introduced as just the reinforcement there. I would say to your question, Jeff, that automotive, in my opinion, is kind of the first place that's really keen on utilizing this. I think the tools to look at it from a structural standpoint in aerospace are a little bit lagging. The ability to put that all into a model and know what that part’s going to do each time is a growing maturity level in aerospace. But I would say automotive is probably the first area. What do you think Johannes?

Johannes Treiber

Yeah, to be honest, I fully concur on that aspect. If you take the high-performance thermoplastics for sure, if you take overmolding from a broad range to the commodity plastics or engineering plastics, they might be different application spaces. But we see the strongest ROI from automotive in metal replacement where in metal replacement, the challenge on aluminum die-cast parts is that you need a high-performance compound or polymer first. And the glass injection molding components are not sufficient anymore in its performance to reach and there we see a very strong drive. So, this local functionalization has its challenges, that the best anisotropic use of composites is not just a classic preformed tape. But the strongest driver we see in the classic composites markets is urban air mobility which probably brings the biggest potential, especially with flying taxis, but even space drones, they need to be manufactured at such high rates in a very short time that overmolding with the requirements for aerospace, with the requirements of certification, etc., are really an interesting opportunity of functionalization being brought into these parts. So that's where we see strong development.

Jeff Sloan 

So the urban air mobility space, even if you apply thermoplastics, as you noted, Trevor, there's a modeling challenge, which I assume will exist in urban air mobility as it does in commercial aerospace. But maybe we have a longer runway there because it's still an evolving and maturing market and what is what is your take on that?

Trevor McCrea

Yeah, for me, and then I'll hand it to Johannes, I feel like the urban air mobility space because it's newer, and a lot of the people involved are a little bit more open minded for product forms, products, processes, the combination, you know, like with injection overmolding, I think they're more apt to look into the way to model simulate and get what they need. I think traditional aerospace, it's just our own nature, it's psychology, where our comfort level is what we know. And so, to be able to kind of crack that open and look at new and emerging things takes a little bit longer in that process to feel well with what was unknown but is now new technology.

Jeff Sloan 

Johannes, do you have anything to add to that?

Johannes Treiber

Yeah, a door could be opened in this space, coming from the smaller aircrafts that transport aircraft, etc. Certification needs are less wherever it's easier to get them certified, and then to prove the technology and then to bring it to life quickly, especially the ramp up and then the needs from the market are so high that this will be put into and fly objects very quickly. And so there we probably have a good learning curve.

Jeff Sloan 

So you mentioned ramp up in demand from this market. We hear different numbers from different people about what this market might look like. Can you give us a sense based on what you're hearing, what your expectations are for this market in terms of demand? How do you perceive the demand for this market?

Trevor McCrea

I'll give you my opinion on it. I think this is a new market and they're going to have to go through the certification challenges, particularly for the manned vehicles. And so the numbers you're going to be talking about in the timeframe is probably going to be a little bit longer than what everybody is hearing. And the numbers are going to be a little bit larger, but it's going to take time and as time rolls, some of the large numbers we're hearing is approaching automotive level. And I think that's why thermoplastics somewhat resonate, because it's not necessarily at this beginning phase of getting certified and qualified, but it's the phase of industrializing and getting into the larger volumes and how you meet rate production. Now, I think that's a strong point for thermoplastic composites.

Jeff Sloan 

So to put some some numbers to this, I'll tell you what I've heard. And then maybe you can respond to that. So, what we keep hearing is that between now and say, 2025-2026, there's not a UAM manufacturer who's probably going to exceed more than 1,000 units a year. And if you're under 1,000 units a year, you can, for the most part rely on already qualified materials using already qualified processes, whether that's hand layup, AFP, but probably out-of-autoclave cure. Once you get past that 1,000 unit per year threshold, you then are getting into rates and quantities where traditional materials aren't going to meet the need. And the window for that is looking like between 2026 and 2030 followed between 2030 and [20]25, with what some people have called full industrialization, which is completely out of the autoclave, highly automated, repeatable, good process control, good in-situ quality checking and fairly high rates up to maybe 10,000 per year, although I think when you're talking 15 years into the future, it's difficult to make assumptions. Is anything I just said make sense? Does that resonate with you? Or do you feel like, Jim, like you just said, are we looking at a curve that's maybe even further out than, say, 2035? Are we looking at 2040?

Jim Pratte

I think it really depends on how long it's going to take for these to get the certification. And, you know, we're focused on the structure part of it, but you have to get into things like air traffic control, and flying over, you know, suburban or urban areas. And I think that's just going to maybe take a little bit longer than people are anticipating. So, I think once they can get clear those hurdles, and people begin accepting that technology, then I think the larger volumes will come and they will probably come very quickly. Whether that's in the 2026 to 2030 timeframe. You know, your crystal ball is as good as mine, or anybody else.

Jeff Sloan 

Okay.

Trevor McCrea

But and I also agree with what you said about a lot of companies were just trying to get off the ground, get their vehicle ready to flight test, whatnot. So, they use the available technologies that they were comfortable with. And now they're realizing, you know, none of that supports our future rate plan. The concern there is when you go out and certify a vehicle out of a certain material set, knowing already that you're gonna have to go back and replace that, that will be a bit of a challenge in the future that has not really been realized yet. They realize it's not going to make rate, and so we get a lot of discussions about thermoplastic structures and materials there, but that company needs to realize they're going to have to revisit a lot of things that may be painful because they've already certified a vehicle under different material set. But I think they realize we're having those conversations and they realize that they need something different to support rate. If they can bring that home before certification, then that's going to be a much easier process.

Johannes Treiber

Yeah, if we take the small aircraft I was talking quite a bit about drones already. Even there, it's amazing to see how much relearning the classic aerospace suppliers are tasked with now to organize and get the manufacturing on route, how much learning and relearning they have to do to bring an automotive mindset for thermoplastic rate capability in there. And that's a steep learning curve. It's definitely seen, even for small aircrafts with a lot less effort, the timeline [is] slipping so for 2025-2026 I would have assumed that that transition is slightly later than that, because this critical stepover to thermoplastics is still a hard one.

Jeff Sloan 

Yeah, because even in the automotive supply chain the qualification environment, there's no equivalent. So, the qualification environment in aerospace is very different from what it is in automotive and so when we talk about aerospace quality and automotive quantity, I mean it sounds nice, yeah, [but] the differences can be pretty stark. I want to wrap up with overmolding. What kind of attributes or what kind of performance characteristics do injection overmolded thermoplastic parts provide that are most appealing to the customers you're talking to? What makes that a good solution for their problems or their challenges?

Johannes Treiber

If I split again between these different markets that we have talked early on about, the classic injection molded parts or where the development comes from the injection molding side, stiffness and creep are probably the most critical aspects for overmolding, which means a composite insert’s dimensional tolerance is crucial. We see a lot of, you know, in automotive, electrification, emo tourist, rotating parts, but even in urban air mobility fast-rotating parts injection overmolding is possible, but there are concerns around dimensional stability. Electric motors, where creep of the part [makes] very good shape tolerances crucial from the classic composite overmolding site for Schwitzer functionalization. It is the ease of assembly, reducing the part number by integrating stiffness but more importantly, even in mounting points assembly points, reducing our sampling error is probably the most critical aspect. We always talk about lightweighting [which is] core in aerospace and in automotive. But in automotive, we repeatedly hear that lightweighting is no paid for. It's actually a necessity to reduce the amount of costly composite that the higher cost composite insert… minimizing it is brings lightweighting but also drives down the cost. It's the rest of the TCO aspect and the rate capability which really make the difference. Lightweighting itself is not valorized anymore.

Jeff Sloan 

Okay. You mentioned rotating parts. Can you talk a little bit more about why creep and dimensional tolerance are so important for rotating parts?

Johannes Treiber

If you take new electric motor concepts, so, not the classical rotor stator concepts but go into a tour of motor for electric cars, you're fast rotating beyond 10,000 rpm, rotating parts or dimensional tolerance is key to large distance to magnets is key to very light tolerances. And because of these high rotational speeds and the need for acceleration and deceleration, the classic metallic components are not as interesting because they have high inertia, but especially in rotor stator combinations, in axial combinations, for example, their dynamic dimensional tolerance is key. And then classic compounds, if you come from the injection molding side and continuous loads is high temperatures which you have in electromotor for example, you will see some creep aspects. Very classical compounds start creeping.

Jeff Sloan 

And I assume that because these are rotating parts, there's centrifugal forces at work and you need to maintain some balance, mass balance, otherwise you can throw everything out of whack, right?

Johannes Treiber

Exactly, it’s a combination. I mentioned earlier it's about what the composite brings as well as the reduced sensitivity thermal expansion issues. If you take a classical injection molded part, as soon as you bring this up to 100-120°C as can be normal in electric motor applications, suddenly they started forming just by the compound expansion, especially if we see them in hybrid applications which we are very keen on. So combined with metal parts, the composite overmolding really can [be] tailored, with the challenge of then designing it accordingly.

Jeff Sloan 

Okay. You mentioned that weight reduction is not valorized in automotive. Why is that? What do you hear from customers about why it's not cherished the way maybe we thought it was or maybe what the way it used to be?

Johannes Treiber

If you take battery boxes, electrification battery boxes, there you can, with two more modules in there, one more module you can easily compensate 1,020 kilos of weight increase, you can simply compensate, but the point is the available space is a lot more critical, for example, for such battery boxes, so it's just one of the aspects where we can more easily address the functionalization, than just trying to sell it by lightweighting. We basically get a lot of feedback [that] he excess or the lightweighting itself is not paid for, it's just we need to be lighter in the first place. Cars gets too heavy, and lighter is not something safe like in aerospace, that's just baseline and you're not getting extra money just for being light in the first place. So we need to always [be] competing our metal solutions, aluminum, for lower rates, deal for higher rates and if you're more expensive then it's just yeah, the costs are here and not so much the lightweighting aspect.

Jeff Sloan 

And by not paid for, maybe that extends to the customer environment. I don't imagine there are many customers who walk into an automotive dealer showroom and ask for the lightest car available. It’s not the way airlines do so.

Johannes Treiber

For sure lightweighting, it’s the benefit in the end. We are doing the metal replacement in electric motor housings, etc. because they get lighter, because every gram counts, but then again in discussions with automotive Tier 1s, we repeatedly hear that within these teams this lightweighting in one area of the car is not accounted for by other teams so it is just part for part, group for group, has a specific target which they need to meet, and everything better than that is not valorized as a whole because the team has a specific target. Other teams are not benefiting by being heavier because another team basically did some lightweighting. So that's a mindset an organization aspect for sure as well and in these companies which we’re fighting, but yeah, unfortunately that's what we see them in terms of lightweighting.

Jeff Sloan 

So we've talked a little bit about the strengths or the benefits conveyed by overmolded parts. What are what are some of the bigger challenges associated with overmolding that our audience should be aware of?

Johannes Treiber

Probably the biggest if you go for structural overmolding every drive for a structural interface for them the predictability and the performance of the interface in the first place. So having a design chain, having a simulation chain for predicting mechanical performance, which is highly complex given that you have a possible one- or two-shot approach, how [you] would make your composite insert impacted by the processing settings, the process window, the injection molding with its flow dependency, its geometrical dependency, so that's the biggest, but then directly followed definitely by design guidelines. You have you add a degree of freedom. We have a complex composite environment where we have a lot of flexibility with stacking with product forms. We have an additional degree of freedom now added by having the compound with its different shapes, its different forms, it's different ways of how to interact from local ribs, to aerial overmolding, to local features. And yeah, so the design guidelines, and for somebody like Solvay, for sure material car generation, you have an injection molding, vast range of product forms of compounds with several product forms on the composite side, and every customer chooses a different optimized combination and suddenly we need to be able to very quickly turn around material card characterization phase, have the interface, the processing team, etc.

Trevor McCrea

I agree with that. And what he's saying, for people that are looking across the spectrum of the different reinforced materials, Solvay has the compounds that work well with those. And like, for instance, with the PEKK material, you tend to like, for overmolding, temperature differentiation there. So the PEEK overmolded material works well with that PEKK material, that's the reinforced part of that. And so, like he's saying, Solvay’s material resource center in Belgium does a lot of this virtual engineering and these data card generation to be able to support that so that our customers, beyond just receiving materials, have the ability to combine those and know what the effects are going to be.

Jeff Sloan 

Right. So as you just said, clearly, Solvay is offering design help, design guidelines, material cards. But you also mentioned earlier, Trevor, the modeling side of this, which is a software issue, which must mean that you were also working with some, you know, the CAD suppliers and what how does that work? How do you take your knowledge about design for overmolding and convey that to a modeling environment that it has value in use to fabricators?

Trevor McCrea

Yeah, I think that's a great question. I'm probably gonna pass that to Johannes because I bet he has better insight than I do into that, because that is exactly what the SEC center and virtual engineering helps with.

Johannes Treiber

It's definitely a challenge. We have multiple activities, engaging on the computation chains. So, it is still a development need for the computational chain of the interface prediction, for example. So, there is directly collaboration with software suppliers, but also collaborative research centers such as TPRC and others really add value by bringing it to a wider attention for our own team on the virtual engineering side. And that shows already in his market we need to bring composites experts, design for manufacturing experts and injection molding experts together to have a cross-functional team engaging on your overmolding opportunities, and then have a strong need for virtual engineering teams coming to bring the topological optimization, the interface characterization and prediction and then design for manufacturing, from the processing side and application engineering side to best use the product forms of the composite side, and the process limitations. Right now, it’s a complex process, which is also coming back to the challenges [of] what I was saying early on. For somebody not having this in place already, [it] is definitely something to work on. Hence, that's why Solvay has a specific reverse-engineering team and an application engineering team working very cross-functionally to support right now industries especially, for example, automotive.

Jeff Sloan 

I wonder what would be the ultimate goal here in terms of modeling and designing for injection overmolding? Would you hope that every major CAD program out there has a module in it that provides the kind of data and the kind of capability and modeling that you need, or do you see that there one or two who are really engaged with this and are working with you closely, and that you see there's promise and opportunity? What’s the endgame here?

Johannes Treiber

From how I see that I assume that there will be a strong link to the glass injection molding side. So, we have Moldflow, mold acts as simulation tools and expansion on these platforms is very likely. To have then expert tools we see on specialty polymers injection molding application nowadays already that there's always a dedicated team engaging. It is not delud[ing] yourself and trial and error. You always have an expert team trying to support customers and customers working closely with material suppliers and end users to really to work through this challenge. But yeah, in terms of software, I expect that it's specialized platforms, specific numbers primarily coming from the injection molding side.

Jeff Sloan 

We talked earlier about qualification for aerospace and for air mobility and I want to revisit that a little bit. You know, the qualification environment is a fairly complex one, we've got some qualification work being done at organizations like N cam at Wichita State University, we have qualification being done by OEMs, you know, for specific parts and structures. Kind of walk me through what the qualification environment might look like for applying thermoplastic composites in a major aerostructure, whether it's for urban air mobility, or maybe even commercial aerospace. What does Solvay that has to be done? Like what would be the ideal environment for you to accomplish that? And what are the options or scenarios? Just give us a sense for what that looks like.

Trevor McCrea

Yeah, I can see from an aerospace perspective, which is more of my background, that there's going to be a lot of test in actual test to back up what's already been simulated, I think, especially in today's like UAM- and aerospace-type environment. I see a little bit, and rightly so, some more conservatism and some oversight there. So less exception of just the virtual tools out there, that I think have really grown a lot, even from the processing and forming standpoint, like AniForm and LS-DYNA, but also, on the FEM model integration with that with overmold flow and whatnot. We're also I think, going to have to do a lot more of the actual testing of those parts, which again, the same MSEC center in Brussels has all of those, you know, abilities to do the high-speed testing, and also a lot of which is usually tied to automotive, but also all of the other testing that's required. And like you mentioned, and with CAM databases and things like that, I think a lot of this is going to have to be backed up across the way with those prototype tests. I think that'll give a good feel across the industry of matching up the virtual with the actual there, and that'll become, you know, people the more used to understanding what the outcomes there with the thermoplastic materials are and integration of say, overmolding and other form types, what's to be expected out of that.

Jeff Sloan 

I assume that work is going on right now. And it will be going on for several years. Is there a reasonable window that you think, like, do you think if we have this conversation in five or seven years that you will be substantially through that major testing and that we will have good qualification data in place that will give us confidence to apply thermoplastic to structures? What kind of timelines do you think it would be reasonable?

Trevor McCrea

Yeah, I think, you know, for like UD tapes, I think some is already available, there's more materials coming out. So I think that will be expanding. It's really the other form types that I think, in the future, will begin to be added to that, the fabrics, the braids, the overmolding, that type of knowledge base, I think is a little bit farther out. It's in-process, but to generate all that and feel comfortable with what's behind that, especially with industries that are newer into thermoplastic applications that may take a little longer to assemble all of that type of data. Plus, as you know, your large OEMs, they like to do this internally and on their own as well, so that may be lagging until we have new products coming on from the Boeing’s and the Airbus’ and those types of things.

Jeff Sloan 

Do you have any Tier 1’s who are interested in trying to develop some qualification data?

Trevor McCrea

Yeah, so several, you know, the largest Tier 1’s, you know, to the aerospace companies, I think like even you know, we were talking about Wichita State and IR and whatnot, I mean, Spirit is right next door down there, they supply both Boeing and Airbus and several others that we talked with, that are very interested in exploring different material options in thermoplastic beyond what they've traditionally looked at in the past, so I do believe that interest will continue and it's growing. I think it would behoove us to have somewhat of a common development, you know, like when the thermoplastic waters rise, all the boats can float a little higher, rather than everybody kind of trying to develop things on their own, so I'm hoping there'll be some good collaboration and working in this area going forward. Like we've even seen with the FAA support for the encamped database values for thermoplastics. I see that as a good collaborative effort for the whole industry to take advantage of,

Jeff Sloan 

Okay, well, that's a very hopeful wish you have.

Johannes Treiber

We for sure still have some key technologies like welding which needs to be progress a lot further in its qualification preparation. It's solely about what we have seen in its initiative internally, which is essentially definitely virtual testing. So driving forward, the virtual testing capabilities, or either the prediction capabilities on shots, that means no longer just first by failure, bringing damage progression, damage modeling, also forward and then using virtual testing, not just received testing. So that's five years from now and forwards, it will be an interesting discussion to see how the industry has progressed on these aspects.

Jeff Sloan 

Okay. Next question. My observation is that the evolution of thermoplastic tapes is lagging [behind] thermoset tapes, for obvious reasons. But we're starting to see thermoplastic tapes deployed in different ways other than just straight UD tapes. So for instance, we're starting to see some braided thermoplastic tapes to develop 2D or 3D preforms. And I'm wondering if you're seeing any of that, and, and what kind of evolution we might expect there in terms of trying to change the format a little bit to make the make thermoplastic tapes do different things for us and provide different advantages.

Trevor McCrea

Yeah, I think that's a great point. And I feel like that's one thing in composites, in general, it's a little bit lagging, especially on the thermoplastic side is designing, you know, the right format for the right part, to have the suite of tools and knowledge base to know okay, if this is the part geometry, this would be the correct format to apply to that, or this would be the correct design. I think some of that maturity is yet to take place, but even like the window frame behind me right here, is done out of a braid that within that flat braid in this instance, and will continue on that, you can imagine, it's one of the trickiest geometries. I mean, imagine a hoop with two joggles in it, I mean, that's not something that's easy to say stamped form quickly. But as we're looking at rate pressure, you got to be able to form a geometry rapidly. And that's where the braids have really come in, to shine there. And there's different types of braids. This one in particular, within each layup is a quasi-isotropic-type layup, so you get very stable and good parts out of that, that also have that tie through that you wouldn't get from a fabric that interlock. So I'm excited about that. And the different formats there I think is going to be a great expansion in looking at what the geometry is, what type of format to apply to that. Same with I have a frame over here that's done out of a braid. I just realized this morning that I've got probably half my parts behind me are out of braided structures as we see more especially you know, applications in seats and interiors, like the structure you normally see at the base that happens to be tubular, you know more tubular structures also in energy transition. So, the braids that I mean initially start as a tubular type structure, this window frame happens to be a flat braid in the end that gets stamped formed but using even within that, whether it's a tubular braid or flattening that braid out. UAM is also an interesting area where they want it very light, and so minimal plies, but they want the most out of what they're using. So, like I mentioned a braid that is quasi-isotropic within that layer, you may only need a couple layers to make whatever that application is. And so it can be very lightweight in that respect.

Jeff Sloan 

Are there any other formats or fiber formats that we should keep an eye on that you feel like, are ripe for development for thermoplastics? You talked a lot about braiding. Are there any others?

Trevor McCrea

Yeah, so within that, the fabrics, whether it's a two by two by 12, or a five harness or an eight, you know, those, and having the data to back those up. Same with the braids, whether it's quasi-isotropic within one layer, or a bimax, that has, you know, 40 fives in there. I think within each one of these, there are multiple options. And so I feel like the knowledge of the advantages and disadvantages of each one of those, that maturity needs to come. But those are some of the new formats. I'm not thinking of ones beyond that right now that seem to be missing, it's really within all these different formats, just developing the maturity of the knowledge base so that more people can use them in the right way.

Jeff Sloan 

So before we wrap up, I have one more question, or did you Johannes, do you want to say something?

Johannes Treiber

Yeah, on the on the tape use. If you take more [of] the automotive side and overmolding, for example, there, the challenge is not necessarily the different product. Braided as one of the products, for example, [is] also of interest given that it's stable, it's mechanically stable against these high injection pressures, and at the same time can be used in very thin configurations, which is always an issue. One of the of the main points is trying to go away from the classic organosheets. And hence tapes, the challenge for tape, not necessarily just a different product form, but made out of tapes, local reinforcements, making tailor blanks, finding approaches, which is not necessarily on the side of them, the material supplier more in between on the conversion, but they're very efficient views, the minimal use and highly orientational use of composites for these kinds of applications, we see this pushing very much. Tapes are key, but at the same time they need to be applied not just in organosheet form, but in in tailored format.

Jeff Sloan 

Okay, so are you saying the braided format is allows tailoring to be applied more easily and more readily, whereas with UD tapes, you've got to have some sort of system that puts the tapes in the right direction in the right place, and in the right, you know, in the right layer to serve that part. Is that what you're saying to me?

Johannes Treiber

It's primarily for thin structures where it braids due to its symmetry, and the multi-directionality and the stability, coming braids coming from tape, but are creating very thin structures, very the classic tape. Either way we need to get two very, very thin tape layers together then again, a symmetric behavior. But that comes to its cost and challenges in making these tapes in the first place. So the upgrades are [a] really interesting intermediate product form.

Jeff Sloan 

Okay. So before we wrap up, I have one quick question, I want to circle back to the urban air mobility market. When we think about applying thermoplastics on an urban air mobility aircraft, are there structures that you consider right for first application? Like when we see thermoplastics first show up on an UAM craft? Where do you think those are? What parts do you think we're gonna see those on first, what would be good targets for that?

Trevor McCrea

I think wing structures are excellent. And then this size, you know, UAM, and even in drones, I mean, your wing sizes are much smaller than traditional aerospace. But the structures inside of them tend to be more traditional and what we've seen previously and so if designed, correctly, even with like a spar, they don't tend to have all of this curvature in there, if designed properly, it could be from a CCM-type of a C channel process, a continuous compression molded type C channel and then you know, as we look at ribs, those are classic opportunities for thermoplastics to be stamped form. So those and all of the interiors and bracketry and all of those types of things, I think are very comfortable, already done in aerospace type of structures as well. It's when we jump to the everything everywhere and thermoplastic. That's where I back out a little bit in this, like, let's look at what is the, I mean, there's the advanced vantage of welding there. But really, let's look at what is a good base to start from, and look at what's the right material for the right application.

Jeff Sloan 

Okay. Great. Well, Trevor, and Johannes and Jim, I want to thank you for joining me here on CW Trending these great comments and insights, and we'll have to revisit a few years and see how all of this is unfolding.