How does bronze infusion works?

#1

Hi, I would like to learn more about the bronze infusion process in steel printed items. I can imagine a machine creating layers of steel powder with a binding agent but what happens after? How does bronze powder replaces the binding agent? It’s not similar to bronze casting? Thx, Koen

#2

Hello Koen,

Thank you for contacting us.

Materials such as steel and high-detail stainless steel also rely on powder but are not laser sintered. Instead, a binder is used to “glue” parts together. We refer to this technology as “Powder- & Binder-based 3D Printing”.

The starting process of this technology is quite similar to laser sintering: a roller puts a thin layer of powder on a platform. However, instead of a laser beam, a special print head places a binding agent at specific points, printing a thin layer of your model that is able to bind to subsequent layers. This process is then repeated over and over again until your model is complete.

Since your model was only “glued” together, some post-processing is necessary with this 3D printing technology. The exact post-processing steps heavily depend on the material: Steel models are additionally infused with bronze for extra strength.

Models made of steel are printed in 420 stainless steel and infused with bronze (Cu 90%/Sn 10%). The chemical composition of the final 3D-printed product will be 60% steel and 40% bronze.

#3

Hi Koen,
some additional wording upon the post-processing.
When the model is printed, it is in a so called green-state. It is still fragile as the glue holds the steel particles together,
The model is placed in a vacuumoven together with bronze.
The oven is heated up to the meltingpoint of the bronze,
The glue burns and the bronze is sucked into the model, replacing the glue and preventing the model from shrinking too much.

Hopes this explained sheds some light upon the post-process.
Wim

#4

Ok Wim thanks , I hope to see this whole process live one day