Binder Jetting
Binder Jetting is a powder bed based Additive Manufacturing / 3D Printing technology.
A binder is used to bond powder particles in the shape of the cross-sections of the model to be built. Due to a broad range of different materials possible to be processed there is a wide range of applications. For years and years, plaster was most the common build material. Coloured resin is jetted through regular inkjet printer heads to create full-colour models for prototyping applications. In recent years, more and more companies developed processes to produce metal parts in a two to a three-step process.
How does the process work?
A hopper is used to deposit the build material and a thin layer of powder is created on the build platform. Subsequently, a binder is jetted on the powder surface. The binder is jetted only on the cross-section of the model bond the powder particles selectively. The platform is lowered by one layer thickness. The next layer of powder is applied and the binder is dispensed. The binder infuses through the top layer and bonds it with the layer underneath. Layer by layer the part grows.
At the end of the process, the excess powder is extracted for recycling and the part can be removed. See a video of the process here
Materials
Sands
“Sands” summarize materials used for casting patterns and cores.
Zircon and Chromite are natural occurring sands which are being used.
But also synthetic materials such as Tungsten Carbide, Silica-Sand and
Iron-Chrome-Aluminium are commonly used.
Metals
A wide variety of metals, which are usually challenging to process with subtractive technologies, are commercially available. Nickel base alloys (Inconels), Tungsten, Cobalt-chrome, Stainless steels, Titanium…
Ceramics
Ceramic beads can be processed to create high-temperature stable parts.
Others
Plaster is used for high-resolution coloured prints.
Glass can be processed mainly for sculptures and art.
Even sugar can be processed for sweet applications.
Applications
Applications for binder jetting can be found mainly in industry but also in the end-consumer market.
Casting patterns and moulds and cores for foundries, jewelry, as geometrically complex metal parts are typical applications.
See also our blog post about the visit at Digital Metal (Höganäs AB) to learn more about Binder Jetting.