3d Print magazine #0

3D metal printing in the manufacturing industry

Many manufacturers of 3D metal printers are currently busy developing their machines for production applications. This is where their future market(s) will be. In a number of aspects they go down the same road; in other aspects their developments differ.

Eric Klemp - director of the DMRC at the University of Paderborn in Germany - expects that, in the near future, 3D metal printers will significantly change in terms of machine design. Traditional machine manufacturers are entering the market; or at least, companies that have their roots in machine construction. They will bring more speed, robustness and stability to the process. "It's going to be 90% machine and 10% additive manufacturing, not the other way round, as is often the case today". Over the last few months, several large players in this market have presented their

vision on this market. Concept Laser may be the most ambitious with the AM Factory of Tomorrow. Essential to this new concept (which the German manufacturer wishes to bring to market at the end of 2016) is the separation of the handling of powder and work piece on the one hand, and 3D printing on the other hand.

Physical separation process steps Concept Laser has chosen for modules. The three key steps in the additive manufacturing process - pre-production, production

and post processing - will be separated. In a separate room, the print job will be prepared in a handling station. This module includes an integrated powder management system, including a sieve for the filter. During preparation, multiple stations can be connected to each other. These handling stations are completely closed, so that operators do not come into contact with the powder. Furthermore, a process module, dosing module and overflow module can also be incorporated, all without directly coupling hoses/tubes and identifiable, using RFID technology. Similar to AGVs, the handling stations automatically drive towards the printing factory, where they connect themselves to the process station, which is equipped with multiple lasers. Once the print job is complete, the module drives towards the post-processing department. "We can automate the AM fabric in many different ways", says Florian Bechmann, head of R&D at Concept Laser. This not only saves a lot of space, but also guarantees a higher productivity. To increase productivity ever further, Concept Laser has developed a new recoater with two axes. These allow the recoater to move back to the starting position while the laser already focuses on the new material layer.

Integrated print line The separation between exposure to a laser and all other operations is also the core of the MetalFAB1, an industrial metal printer developed by Additive Industries in Eindhoven. The Dutch startup chose to separate different steps and to place them in separate modules. At the same time though, it integrates them in a single machine. The transportation of the construction board of, for example, the unit used for printing to the unit used for heat treatment or storage, is done by a robot. The robot moves along a track at the rear of the machine. Unique to this solution is that the MetalFAB1 features up to four print rooms. “The optical system can switch from one room to another”, says Marc Vaes, technology manager at Additive Industries. “This allows us to process multiple materials at the same time." The positioning of the unit is precise enough to do so. Customers can equip the optical unit with 1 to 4 lasers that can reach the entire construction surface. This prevents so-called 'stitching' in the transition areas between the lasers. A second area in which MetalFAB1 differs

from other machines is the integration of a heat treatment oven. The Dutch manufacturer's aim is to be able to remove the completed product from the machine. For the most part, the excess powder is automatically removed and reused, without being discharged from the machine.

Multi laser system Other manufacturers are working to make 3D printers more suitable for manufacturing applications. For example, several years ago EOS introduced the AM 400. The AM 400 has a separate station for the removal of the construction board and semi automatic removal of powder. This multi laser system will be brought to market before the end of this year. Adrian Keppler - sales and marketing director at EOS - says: "Multiple lasers in a single system reduce the processing time. In combination with having the handling of powders and work pieces done outside of the machine, we can reduce the costs per printed work piece. This is the first step towards industrialization." For EOS, it is especially important that the 3D metal printers can easily be integrated

in an existing production environment. Therefore, no Industry 4.0 concept. "There will only be a few AM manufacturers that will be built from a green field", explains Keppler. The way in which EOS allows for the use of multiple lasers opens up many new possibilities. By having different settings in the software, multiple lasers can be used to build multiple products at the same time. For example, a machine with four lasers can print in four quadrants at the same time. This reduces printing time by 75%. The lasers can also simultaneously work on one element. Furthermore, EOS is currently also developing a software package to which not only 3D printers can be connected, but also other types of production printers. "We don't want to offer a single machine, but a complete manufacturing solution", says Keppler.

Software suit required for all manufacturing data Software in machines is of increasing importance. Additive Industries has developed a realtime monitoring and planning system that works independently from the location of

the users. Furthermore, the system is fully open, so that other systems and machines may also be connected. The next step the company wants to take is to use big data to analyze the many process parameters and potentially adapt the process to these data. Furthermore, Additive Industries has integrated automatic calibration in the MetalFAB1. This system calibrates both the focus of the lasers and the position of the laser spot. Marc Vaes:

"For every layer, we check whether the laser is correctly aligned and inspect the position and focus." Because the optical unit positions itself at a micron accuracy, potential deviations due to thermal drift of the machine can be prevented. Customers of the Dutch machine builder may also select the PrintRite3D package of Sigma Labs. Using this package, one can monitor the buildup process in realtime.

Meltpool control EOS has expanded the existing quality monitoring system with Eostate MeltPool process control. The basis of this system comes from checking the laser welding. Together with partner Plasmo Industrietechnik, EOS has adapted the algorithm to the laser melting of the metal powder. Per printed element, the system (two photo diodes and a camera and signal amplifier) detects whether or not the melting process meets the requirements. Users can set up the accuracy per print job.

Q modules For a long time now, Concept Laser offers multiple quality modules for its machines, partly to monitor the state of the powder and gas and the recoating process. QM Meltpool is the most essential module. Concept Laser uses a special camera during the melting process per square mm. This is a highresolution camera with a frequency of 10 Khz. This guarantees lots of data, which are analyzed in realtime. In the future, Concept Laser aims to introduce an adaptive process by having the machine adapt itself to the data made available through various quality systems.

SLM Solutions: multilasers SLM Solutions allows for the manual transport of the construction board to the post-processing location. The North German manufacturer especially focuses on the development of multilaser technologies and process control. SLM Solutions offers a total of four laser sources in a machine. This Qua laser in the SLM 500 HL reduces build-up time by up to 80%. The smaller machines - the SLM 280 HL and SLM 500 HL - can now also be equipped with a 700 W lasers, reducing the printing time in these stand-alone machines.

Additive Industries www.additiveindustries.com Concept Laser www.conceptlaser.de / www.landré.nl EOS www.eos.info / www.benderam.nl SLM Solutions www.stage.slm-solutions.com

Renishaw: integrating 3D printing into the existing product line

This is what a future 3D printer line at a supplier looks like according to Renishaw's vision. The 3D metal printer, used for printing one type of material, is integrated into a row of measuring and milling machines for a complete product line.

On the road towards production applications, Renishaw has taken a different path with its new 3D metal printer: the AM 500. Powder handling and laser melting are integrated into a single machine. However, the machine contains two containers, one for new powder and one for recycled powder (which is automatically recycled in the machine). As a consequence, less powder is required. More importantly, the quality of the work pieces improves because there is a constant stream of new and recycled powder available. As a result, the quality of the material flow remains the same. In doing so, Renishaw also increases the length of time that the machine can actively print. The machine is also equipped with a double filter system, so that the filter can be changed during printing. To increase accuracy, the AM 500 has an optical unit using Renishaw's own technology, such as encoders for accuracy positioning. Renishaw's vision on the step from prototype to AM for production is reflected in the machine concept of the AM 500. Philippe Reinders Folmer, director of Renishaw Benelux says: "We believe in an additive manufacturing line in which the printer is integrated into a row of measuring and post-processing machines. We also expect that companies will choose for a mono material strategy: one material per printer, which ensures optimum production."