AIM3D, based in Rostock, Germany, has announced that it has been granted fundamental European and US patents for its compact, decentralised pellet extruder and Material Extrusion (MEX) Additive Manufacturing with high-temperature materials. The US patents also include Fused Deposition Modelling (FDM) AM for high-temperature applications and high-flow hot ends.

“We now believe more than ever in our CEM technology,” stated Dr-Ing Vincent Morrison, CEO. “The granted patents reflect our impressive achievements in research and development as pioneers in 3D pellet printing. These patents secure our know-how for 3D pellet printers. At the same time, we are open to establishing licensing partnerships.”

Since 2017, AIM3D, a spin-off from the University of Rostock, has been consistently focused on pellet-based Additive Manufacturing rather than those that process filaments. Significantly lower material acquisition costs for pellets and the inline recycling of reclaimed material form the basis for the high cost-effectiveness of this AM production strategy. The development work on pellet Additive Manufacturing technology was reflected in four patent applications between 2016 and 2018, which have now been granted in 2023. The patents protect both the topology of the AM extruder as a whole and the detailed technical solutions in the area of pellet processing

Published patents

The patents granted are published as EP3463799B1, EP3648946B1, US11541593B2 and US11597118B2.

• EP3463799B1 (application: May 27, 2016) – ‘System for the additive manufacture of metal parts’
• EP3648946B1 (application: June 26, 2018) – ‘Compact extruder and extrusion of thermomechanically deformable pellets’
• Patent US11541593B2 (application May 27, 2016) – ‘Extruder for a system for the additive manufacture of metal parts using the composite extrusion modeling (CEM) method’
• The US patent US11597118B2 (application: June 26, 2018) – ‘Device and method for the extrusion of thermo-mechanically deformable materials in bulk form, and compact screw extruder’

Significance

The thermal separation of the housing and the division into an actively cooled and a heated area of AIM3D’s Composite Extrusion Modelling (CEM) lead to a short melting zone and uniform extrusion at high build rates (based on nozzle sizes of 0.3-0.6 mm).

This becomes particularly evident in the processing of ULTEM 9085, a material that is of great importance in the aerospace sector, which can be processed by AIM3D’s patented pellet extruders in a material-friendly and reliable manner with high build rates and very good surface quality. The design of the extruder is said to guarantee a short melting zone, which prevents degradation of the material inevitably leading to process fluctuations and weak points in the components. In combination with the active filling of the extruder’s feed area, it enables a uniform static and dynamic pressure in the extruder, which in turn leads to uniform extrusion widths and, therefore, a high component quality.

Beyond the processing of metal-filled composites (as mentioned by name in the patents), the system-specific patent claims to also extend to the processing of thermoplastic polymers, as long as the system-specific elements are found in the systems and the processing of metal-filled composites (for example, MIM material) cannot be technically excluded.

The US patent US11541593B2 — ‘Extruder for a system for the additive manufacture of metal parts using the composite extrusion modeling (CEM) method’ — describes the topology of the thermal separation. In addition to the use of pellets, which are fed into the melting unit via a screw, it expressly includes the use of sticks or filaments, which are advanced via drive wheels. In principle, the protection of the US patent thus also applies to hot ends and extruders of filament or stick-based systems that use thermal separation in the melting unit, for example, in order to achieve higher flow rates or for the processing of high-temperature materials.