XERION (formally XERION Berlin Laboratories GmbH) is a company best known not for its additive manufacturing but for its advanced heating solutions. Still, that hasn’t stopped the German company from bringing its own AM innovation to the table. In fact, XERION has leveraged its expertise with heating technologies, such as furnaces, to develop a fully integrated metal and ceramic 3D printing system: the Fusion Factory.
The Fusion Factory, in short, is a modular AM system that consists of a metal filament-based 3D printer, a de-binding unit and a sintering furnace. The driving force behind the technology was to bring an affordable and versatile industrial AM system to market—versatile in that it can be used with a range of metal filaments or ceramics.
Curious about the new AM platform—which Formnext visitors may have had the chance to catch a glimpse at—we spoke to Siddharth Tiwari, the head of R&D at XERION, about how the platform works, what stage the technology is at and how it could impact the metal and ceramic AM industries.
“XERION is a company that was founded 20 years ago in Saxony Germany,” Tiwari begins to tell us. “And since 2016, we have operated a research and development center here in Berlin. Traditionally, the company makes furnaces for high temperature applications (ranging between 30 and 3000°C). Our work basically encompasses applications related to material testing, material manufacturing and characterization of materials at very high temperatures.”
It was about three years ago that XERION first began investigating additive manufacturing technologies at its R&D lab along with partners at the Fraunhofer Institute.
Tiwari elaborates: “The idea was to use a normal desktop 3D printer which could use special filaments which contain high percentages of metal and could be processed at relatively low temperatures, let’s say 150 to 200°C. After printing, naturally you have a part made from metal and non-metal components and to get rid of the non-metal particles you have to heat treat it at higher temperatures—about 1300 °C. That’s where we came into the picture three years ago.”
Advantages of filament-based metal printing
“There are a lot of advantages to filament 3D printing for metal,” Tiwari tells me. “Number one, SLM machines require the use of fine metal particles, which represents a health hazard. Filament is free of that risk. Another advantage is that the material utilization with filaments is very good; if you put one meter of filament in, you will use one meter. There’s no wastage of the raw material in that sense. Of course, it can happen that a print breaks, but in theory there is no material waste.”
“The third advantage,” he continues, “is you can print with multiple materials. For example, if you want to print an electronic circuit board, you can print the ceramic base and on that you can print with copper. And lastly, the filament has the advantage of being cheap. If you talk about the general price of filament on the market, it’s around 250 euros per kilo, and that price will continue to go down as the materials become mass produced.”
In terms of the multi-material capacity of XERION’s AM platform, Tiwari explains that it’s something that is already happening at the R&D lab.
“We have tried to print with both metal and plastic so far, which is not that simple because our filament has temperatures of 120°C and PLA, for example, has a higher temperature of about 240°C. We have also run some tests with ceramics which are especially interesting to us as a furnace manufacturing company.”
“Imagine you want to print a small heating element,” he adds. “You could print a ceramic base then you could use another nozzle which has a metal filament to print the profile of a heater, and then you could print another ceramic layer to isolate the heater. Basically what you’d have is a portable, very customizable heater that you could place just about anywhere.”
The question of hardware
“The 3D printer we have is modified to work with metal and ceramics and right now we have two nozzles built into the machine,” Tiwari said of the 3D printer. “We do have plans to go up to four nozzles, but this will likely happen in a year’s time.”
For the de-binding station, he explains that though XERION initially explored thermal debinding, it ultimately decided to use a solvent-based debinding process.
“In our case, the chemical is acetone, but it can also be alcohol-based,” he says. “The advantage with the liquid is that it can go uniformly into the whole structure. It goes into the part’s micropores and eliminates the binder from deep within the matrix of the material. What you’re then left with is loosely bound together metal which needs to be sintered at high temperatures to fuse the metal particles.”
Living in a material world
“Right now we are focusing very strongly on stainless steel,” Tiwari tells me. “The grades of stainless steel we are working with as 17-4 PH and 316L, two of the main grades used in industrial applications. We are also working with technical ceramics including aluminum oxide and zirconium. Hopefully, let’s say in a year or so, we will also be working a lot with copper. We’re going to be starting a research project to develop a copper filament, which will be interesting for people who want to do prototyping of electronic parts.”
“The filaments we are using are not developed in house,” he notes, adding that XERION is not a materials research company. “We are developing them with a company here in Germany and other partners. We are trying to work with partners to be able to develop multiple filaments that have more of less the same melting point. That’s the trick with multi-materials: you have to get materials with the same binder so that you can achieve high accuracy.”
Looking at applications for the Fusion Factory system, Tiwari explains that XERION initially set out to make a system for the spare parts industry, to 3D print parts for industrial machines to eliminate or reduce down time when a part breaks.
“If you have a Fusion Factory in house, you can replace the part that broke in two days,” he says. “In the meantime, the manufacturer can order another part for a long-term replacement. With the 3D printed replacement at least you don’t have dead time with the machine.”
Through the development of the Fusion Factory, however, the target market shifted slightly. “Though our main motivation was spare parts, it eventually started moving towards prototyping. The prototyping of complex parts which would be impossible to make using traditional processes and parts which are so expensive you wouldn’t care to get them manufactured. So right now, it’s going more in the direction of metal prototyping, but hopefully in two or three years it goes more into manufacturing.”
“Ceramics is also very interesting, but at the same time challenging,” he continues. “The market for ceramics compared to metals right now is small. That is one of the reasons why it’s progressing at a slower rate than metals. But we took decisions while designing our machine to ensure it would be compatible with ceramics as well. For instance, when you sinter metal, you do it in a hydrogen environment, but for ceramics you need air. So we developed a special furnace that can work in hydrogen and air.”
Behind the hardware
The Fusion Factory system also integrates a Siemens-based control unit aimed at making the AM process as efficient as possible.
Tiwari comments: “Because we are working with explosive gases like hydrogen, we have a special redundancy built into the control system, meaning that more measures will be taken to detect errors. Besides that, another advantage is that all the hardware units, including the printer, are connected to the control unit. You can get housekeeping data from the printer—about temperature, how far along the print is, etc.—from the debinding station and from the sintering furnace. All the information from them is collected and turned into reports.”
“For example, if you make a part you will get a report saying what the print parameters were, what the conditions for the acetone were and what type of heat treatment was used,” he elaborates. “So if the printed part breaks after years of use and you want to analyze why it broke, you can look at the report for full details. The control unit also offers advantages from the point of view of repeatability in that you can input an existing print profile.”
Going to market
“The Fusion Factory, if I’m not mistaken, is one of the first of its kind in Europe,” Tiwari reveals. “I don’t think there is an integrated solution like the Fusion Factory in Europe with this technology. You have some machines in North America, like Desktop Metal and Markforged, which are doing similar things, but they have much more funding than we do.
“Our aim is to be able to sell the complete factory to manufacturers. Since the Fusion Factory is built on a modular concept, certain modules can be removed. For example, if somebody already has a printer and wants the debinding station and furnace then we can take out the printing module.”
When I ask about the level of automation of the system, Tiwari explains that currently some manual work is needed to move parts from one unit to the next, but that XERION plans to add more automation in the form of an enclosed, conveyor belt system.
“The Fusion Factory is not an R&D project anymore,” Tiwari emphasizes. “It’s a mature technology. It’s ready to enter the market. So it’s not an R&D project that we promise clients they will get in two years time if they preorder. It’s a machine that is ready to be used.
“We hope to receive some purchases and order requests soon. At this stage, clients are mostly interested in the technology for prototyping and research. Since our machine is very flexible and customized, it’s great for research institutions that are exploring AM or who want to test and produce electronics.
The XERION team presented the Fusion Factory publicly for the first time at Formnext 2018 earlier this month along with sample parts printed on the machine.
“This was the first public presentation of the machine since it’s conception and it was very well received by the 3D printing community,” Tiwari concludes. “With over 25,000 visitors attending Formnext and numerous B2B meetings carried out during the course of the fair, XERION is confident that the fair will serve as a launchpad for future collaborations as well as sale of the Fusion Factory, and more importantly further enhance filament based printing’s reputation as something which can do more than just produce plastic showpieces.”