Fabricating geometrically-complex B4C ceramic components by robocasting and pressureless spark plasma sintering

Robocasting and pressureless spark plasma sintering are combined for the first time to fabricate geometrically complex B4C components. It is shown that robocasting allows B4C green pieces to be printed with near-net shape from inks with suitable rheological properties, and that subsequent pressureless spark plasma sintering permits an ultrafast, energy-efficient, solid-state densification that yields B4C parts with adequate mechanical properties. Furthermore, the usefulness of cold-isostatic pressing to improve the densification of the pieces is evaluated, and the benefits of robocasting over conventional dry powder compaction are identified. Finally, the scalability for the production of large B4C pieces is discussed. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.