The AIM3D process
The patent pending CEM process (Composite Extrusion Modeling) is the core element of the AIM3D printers. It combines the well-established metal injection moulding process with the innovative additive manufacturing techniques.
The result is a simple process that is based on cost-efficient and readily available injection moulding pellets and offers the freedom of additive manufacturing processes without the need for moulds.
The CEM process considerably reduces both material and machine costs. Furthermore, known issues in metal manufacturing, such as residual stresses, are significantly reduced with the CEM process.
During the 3D printing process, only the plastic component of the MIM pellets is melted. The metal powder, which is bound by the plastic, then forms a so-called green part, which is still quite fragile.
In the next stage of the process, the plastic is first debinded, which means that the binder is chemically or thermally dissolved. Finally, the temperature is raised in a sintering furnace to just below the melting point of the metal. The metal particles then bond on a molecular level and form a stable metal part.
Due to this process, the sintered part shrinks. This shrinkage is largely homogeneous in all three spatial directions and depends on the printed material. It can thus be taken into account by simply scaling the desired geometry of the part before it is printed.
FAQ about the CEM process
Can any type of pellets or granulates be used?
Can any type of pellets or granulates be used?
Our ExAM printers are open material systems. Hence, customers can usually use their own existing materials. In the end, the chosen material dictates the minimum nozzle size and the general printability.
Can I use commercially available MIM feedstock?
Can I use commercially available MIM feedstock?
Yes, you can. It is not even relevant which binder is used. The ExAM printers support all common debinding methods (thermal, water-soluble, solvable and catalytic).
Does the entire production process of the metal component take place in the printer?
Does the entire production process of the metal component take place in the printer?
No. After the 3D printing process is completed, an additional debinding step is needed to remove the plastic and a sinter oven is needed to seal the component in an additional sintering step. AIM3D‘s open materials system allows you to keep using your already existing debinding and sintering systems.
Can I debind and sinter my 3D printed parts together with the parts produced by metal injection moulding?
Can I debind and sinter my 3D printed parts together with the parts produced by metal injection moulding?
According to customer feedback, this works very well. Hence, you can save time and money by not having to include separate sintering steps for the parts produced by additive manufacturing.
What are the mechanical properties?
What are the mechanical properties?
In general, the spec sheet values of the MIM material can be achieved, because the mechanical properties of the final component are mainly dependent on the sintering step. This is, in particular, also the case for the z-direction of the component.