EOS is the world's leading provider of 3D printing solutions and offers professional 3D printers, materials and software from a single source.
In order to fulfil the different requirements of customers, the solutions have different levels of automation. AZO has been an innovation leader in the field of intelligent and automated powder management solutions for over 75 years and is therefore the ideal partner for EOS.
The world is changing - even in raw material automation and manufacturing processes. The only constant: everything starts with your raw materials as the basis for your quality products. However, the properties of these raw materials could not be more different.
Some are true free spirits, i.e. difficult to control because they are free-flowing, shooting or dusty. Others, on the other hand, are real divas and are considered challenging raw materials - highly flammable or explosive. There are also sensitive raw materials that need to be automated with extreme care as they are fragile or segregate easily. Recalcitrant raw materials are considered to be real stubborn heads due to their properties, such as clumping, sticking, poor flowing, etc. The final member of this illustrious group is the meanie: these raw materials are often very special and pose major challenges for automation. They are often abrasive and toxic and therefore dangerous for the system and the operator.
The polymer powder used in 3D printing also poses some particular challenges. One of the biggest problems is static charging, which is why the conductivity of the powder must be improved. As fine powders are generally explosive, appropriate precautions are also necessary here. In addition, operator protection is particularly important, as the powder can irritate and dry out the mucous membranes. Glass and carbon-reinforced powders often have poor flowability, which makes the production process even more difficult. Some preparations must therefore be made to ensure safe and trouble-free operation.
The collaboration between EOS and AZO began in 2019 with the first series of trials in which functional components such as screening, conveying and mixing were tested. In the following years, both companies carried out further trials, which yielded promising results in terms of throughput rates, homogeneity and the reduction of static charge.
As part of the cooperation, EOS and AZO worked together on various research projects. A significant milestone was reached in 2023 when a successful project was completed at a renowned racing team. Also in 2023, AZO developed a fully automatic powder feed system for the EOS printers. The convincing result of this development ultimately led to the two companies entering into a strategic partnership.
The expectations placed on raw material automation and its functions are manifold:
The AZO powder handling system supplies the customer's printers with new powder or recycled powder. The system consists of a big bag emptying station with a buffer container for feeding new powder and two buffer containers for storing used powder (powder after the unpacking process) and overflow powder. The different powder qualities are dosed into a conveying line via dosing screws at the outlet of the buffer containers. The powder reaches the screening and mixing station with the aid of a vaccum conveying system.
The product delivered from the buffer containers is screened in the cyclone screener and coarse particles that are produced during a print job, for example, are automatically discharged. The screened powder is conveyed into the AZO®MIXOMAT via vacuum conveying. This is a mixing and weighing station with which different recipes can be weighed and mixed in one device. In addition, the AZO®MIXOMAT is conditioned to accelerate the dissipation of static charge. After mixing, the homogeneous powder mixture is emptied into a downstream container so that a new conveying and mixing cycle can be started immediately.
The prepared powder (after the screening/mixing process) is distributed from the mixer hopper to the buffer containers connected to the printers by means of vacuum conveying. The prepared powder can now be fed from the buffer containers to the assigned printers as required. The overflow powder produced during the print job is conveyed from the printer into an AZO intermediate container, where it can cool down for further processing. This container also ensures a clear separation between the printer and the AZO vacuum conveying system. After a predefined cooling time, the overflow powder is conveyed into the corresponding buffer container and is available for the process again. The used powder produced when unpacking the finished component is transferred directly to a vacuum conveying system during the depowdering process and conveyed via a receiver into the assigned buffer container and is thus available for the process again.
To summarise, the AZO-EOS concept offers the following solutions for powder supply in 3D printing:
This concept enables a fully automated and efficient powder supply for 3D printers. It ensures that powder of different qualities is stored, prepared, mixed and reused. Safety and quality requirements are also met by the filter system and the minimisation of static charges.