Shaping of ceramic by binder jetting
Résumé
Additive Manufacturing by binder jetting is becoming increasingly popular to process ceramics. This layer-by-layer
technique consists in building up a part from powder beds on which a binder is selectively deposited. Such technology is
not only highly productive but also all-material compatible and is one of the few truly “free form” additive technologies.
Unfortunately, it suffers from a series of limitations that are not yet fully resolved. These include the low density of the
sintered parts, which makes them unsuitable for structural use, and the rather rough surface of the parts produced. A
significant research effort is underway to overcome these limitations. The literature is full of attempts to improve this
technology either with extensive work on the powders or with significant hardware modifications.
This presentation reports preliminary results obtained on a new type of hybrid binder jetting equipment used to
manufacture of alumina parts. The system is not only an additive one but also a subtractive one: it comprises an in-situ
mounted laser whose purpose is to refine the contour of each printed layers thus enhancing the overall part resolution
and smoothness.
The presented results describe the optimal operating conditions with two different binders to ensure a maximum
densification after sintering. The benefit of a post-infiltration of parts with a loaded suspension is highlighted. Alumina
parts with densities up to 88% of the theoretical density have been produced.