Gühring, based in Albstadt, Germany, has released a new nozzle, the DIANOZ, equipped with a diamond tip and designed for Material Extrusion (MEX) processes such as Fused Filament Fabrication (FFF). The nozzle is specifically targeted for high-wear applications such as metallic and ceramic-filled materials, PLA, carbon fibres and PEEK.

The nozzle in filament or pellet-based MEX Additive Manufacturing is one of the most wear-prone parts of the machine. However, Gühring aims to overcome this problem with the introduction of this new diamond-tipped nozzle. The nozzle serves as an interface between the AM machine and the component and plays a crucial role in the build quality. The build process and the final product can be negatively impacted by wear and poor thermal conductivity.

Worn nozzles often hinder a smooth manufacturing process; worn nozzle tips lead to poor build results and unclean surfaces with droplet-like excess material. To compensate for wear, the nozzle clearance requires time-consuming adjustment, a process that requires a build to be stopped. This pause is required as it is impossible to continue without quality loss resulting from changing in parameters.

In addition to wear resistance, the thermal conductivity of the nozzle has a significant impact on the build process. Materials such as ruby (corundum) on the nozzle tip are thermally insulating and, therefore, affect build quality and process reliability:

• unclean, rough surfaces due to uneven filament flow
• the set value deviates from the actual temperature on the tip and makes accurate, process-reliable manufacturing difficult
• the insulating effect is compensated by increasing build temperature by up to 15°C and constantly increases energy consumption

As the hardest natural material in the world, diamond offers the best wear protection – including as an insert in the nozzle tip. Additionally, it conducts heat extremely well, resulting in even Material Extrusion and smooth surfaces. Gühring states that no other material can combine these two properties as effectively, which is why its nozzle is reinforced with synthetic diamond. These diamonds – also known as polycrystalline diamonds (PCD) – have the same chemical and physical properties as natural diamonds and are just as hard and thermally conductive.