TCT Magazine: Q&A: Incus GmbH discusses its metal photopolymerisation 3D printing technology

In late October, Incus announced the launch of its metal photopolymerisation technology, which has been developed within Lithoz’ R&D facilities in Vienna over the last few years, and promises ‘the finest of surface structures’ using materials with similar properties to metal injection moulding. As the company debuted at Formnext, TCT Magazine dropped by the stand to pose a few questions to CEO Dr Gerald Mitteramskogler (GM).


Can you explain how your metal photopolymerisation process works?


GM: We’re using a lithography-based approach for the production of metal powders. Similar to Lithoz, we have photopolymer resin that is filled with metal powder. We use finer powder, so basically all of the powders that are possible for metal injection moulding are possible with our approach as well. So, using the principle of stereolithography or vat photopolymerisation or DLP, we are creating, layer by layer, a 3D printed green part. The green part is the mixture of the photopolymer that’s holding together the metal powder and then we put the green part into the sintering furnace for debinding and sintering. And because we use stereolithography instead of a laser beam or melt pool or inkjet print head, we can achieve the highest possible resolution in the additive manufacturing of metals.


How does your process achieve good surface quality of parts?


GM: We’re using a liquid feedstock instead of the powder bed because the biggest problem in powder bed processes, binder jetting and powder bed fusion, is that they spread the powder on the powder bed [and you can] create streaks and flaws in the coating process. And this is what we don’t get when we coat the liquid layer on a solid surface because our feedstock has a butter-like behaviour. At room temperature, it’s solid, and at our coating temperature, around 30°C or 40°C, it’s liquid. So we are always coating a liquid layer on a solid surface and this is what creates this homogenous coating quality and, together with the projector, that’s the essential thing in creating the high surface aesthetics we see in our parts.


What materials can you process on the Hammer Lab35 machine?


GM: We have the most experience with stainless steel 316L, but we’re also working with titanium 64 right now and developing the debinding and sintering cycle. We have industry cooperations going on in tungsten carbide-cobalt for cutting tools or cutting tool holders. We’re also working with pure tungsten, copper, we have also printed magnesium before so it’s as I said, any material that is possible in metal injection moulding can be processed on our printer so we’re just looking for customers that are willing to develop the debinding and sintering for us because our core competence is from powder to green part, but after green part, we require partners that know debinding and sintering or at least have experience in that.


The Hammer Lab35 forms part of a modular package that can be tailored per customer. What else can users access through this package?

GM: So, if we have a customer from metal injection moulding, we only need to offer them the 3D printer, they have all the debinding and sintering [equipment] in-house, they don’t need our experienced there. But if we have a customer that wants to have a turnkey solution, we have competent partners, for instance MetShape. Their background is metal injection moulding, they can provide the next steps after the green part for debinding and sintering. We also have collaborations with furnace suppliers so if the customer wants we can really provide them a turnkey solution. We give them our printer, we provide the materials, we provide the furnace and we provide the furnace parameters so we can guarantee the customers will get proper material properties at the end.


And, of course, we have training and support along the printing process and debinding and sintering as well. We want to make sure that the customer is actually able to produce parts. We want that our technologies are used on the market and we create some really nice products out of it.


How long has the technology been in research and development?


GM: I joined Lithoz four and a half years ago through a research project called REProMAG. There, we tried to print the metal powder. So, in this case it was magnetic powders on the Lithoz machine and this is when we figured out Lithoz is great for ceramic materials but with metal powders it’s a little bit tricky. After two years playing around with the Lithoz machines, we decided we needed to change something and come up with something new. It took us about four prototypes to come up with the final system at the end. About a year ago, we decided we needed another push to get it out from the research level within Lithoz out to market and decided to found Incus.


Can you explain the decision to spin out Incus as an independent company, rather than just expanding the Lithoz portfolio?


GM: The decision was because when Lithoz was founded in 2011, there was basically no ceramic printing out so Lithoz had always had to pull the market and develop the ceramic 3D printing market. The situation with metals, as you can see around here at Formnext, is completely different. We have so many different companies out there doing similar stuff. You have a lot of indirect methods or two stage processes like binder jetting, the powder fusion guys, so we have a different market and we decided we needed a different approach in growing the company. Also, in terms of target companies, there’s hardly any companies that are doing ceramic and metal so we have a different target group.   


We will work with Lithoz where synergies are possible. We are licensing the Lithoz software package, because why develop our own software if Lithoz already has the perfect solution? Also, we’re using similar components [in the Hammer Lab35] that have been proven in the Lithoz product – why should we do anything different in engineering? We will try to use synergies like in marketing, trade fairs, sales partnerships. There will be close ties but Incus will still be an independent company.


What can you tell us about the company’s product roadmap?


GM: What we presented this year at Formnext is our laboratory scale machine. As the name suggests [Hammer Lab35], it’s intended for small scale production, for material development on the laboratory scale. We have ideas, concepts that are the same as the others are doing in terms of binder jetting, go big in terms of platform size to increase the productivity, lower the cost per parts. And we are also working with our beta customers and early customers to figure out what they actually need in terms of platform sizes and parts sizes, what they actually need to be efficient.


You can read the article here.