Voxeljet
Voxeljet has announced the development of a new ceramic material for the 3D printing of investment casting shells and cores in collaboration with AGC Ceramics Co., Ltd (AGCC).
The new Brightborb material was developed by AGCC and qualified in Voxeljet’s Material Certification Lab in Friedberg, Germany. It is expected to be commercial available from July 2021, both for printing systems and via Voxeljet’s on-demand services.
Developed on Voxeljet’s VX1000 platform, Brightborb is applied to the build platforms with average grain sizes of 50μm, layer thicknesses of 100μm and selectively bonded with an inorganic binder. This binder is characterised by its high environmental compatibility as only water vapour is produced during moulding and helps to improve the environmental and working conditions of foundries. To prepare the printed ceramic for its final application, printed parts get impregnated by a silica-based liquid and are then fired in a sintering furnace. Most of the unprinted powder can be reprocessed, recycled and fed back into the printing process.
Brightborb has been developed to produce investment casting cores to enable complex and filigree cavities within castings. Here, filigree cores are combined with conventional wax patters, coated with a ceramic slurry and burned out before casting. A hollow ceramic mould will remain in which the printed core is inserted, before molten metal is poured into the mould. After cooling, the mould and the core are removed.
“We have been noticing a growing demand for increasingly complex component geometries among our customers for a long time,” commented Voxeljet CEO Dr Ingo Ederer. “The great advantage of the geometric freedom of 3D printing is that geometric adjustments can significantly optimise the efficiency and effectiveness of, for example, engines or turbine wheels. It is rare that such complex components can still be produced using conventional moulding processes. Together with AGCC, we have been able to optimise a VX1000 for ceramic powder in close cooperation, so that it is ideally suited for the challenging demands of metal casting. Both in terms of strength and surface quality.”
“Brightborb is a high-performance ceramic that is extremely well suited for metal casting due to its high-chemical stability, heat resistance, thermal conductivity and low thermal expansion,” added AGCC Additive Manufacturing Director Mr Ushimaru. “We were able to optimise the material set in such a way that the shrinkage factor of the printed components during the downstream sintering process at 1,400°C is less than 1%. This means that the components are also suitable for filigree core designs. Thanks to the high fire-resistance, it is possible to cast alloys with melting points beyond 1,600°C. Overall, ceramics will continue to gain importance as a material in the future, and the same applies to 3D printing as a manufacturing technology.”
Want to discuss? Join the conversation on the Additive Manufacturing Global Community Discord.
Get your FREE print subscription to TCT Magazine.
