Sintering transforms a brown part into a fully metal part. To do this, the temperature is ramped up slowly to burn away the trace amounts of remaining binding material. As the temperature ramps up closer to the melting point of the material, the metal particles fuse together to create a strong metal part.
The Markforged Sinter-2 is a furnace designed for mid-volume production runs and larger printed parts. The Sinter-2 and other Markforged sintering furnaces use a carbon-free retort to ensure part quality and alloy composition standards are met for finished pieces.
Each run takes about a day and can be monitored remotely using the Eiger software. Once a run is complete, the setter tray with finished metal pieces can be removed from the furnace. Once removed from the raft, these parts are ready for use.
In the furnace, the layer of printed release material between supports, rafts, and your printer part turns to powder. This allows the structure to be tacked to the raft to better control shrinking and accuracy throughout the process, but also an easy release after sintering.
At this stage, your part is fully sintered and ready to be used. It can be post machined, polished or otherwise processed as necessary for the final application, but in many uses the accuracy and strength of the part after this process means its ready for installation.
Through this process, you can see how metal 3D printing provides a safe and cost-effective method of metal additive manufacturing. These processes are already driving innovation in lean manufacturing.
This is manufacturing redefined!