Additive manufactured replica foams

Abstract

The Replica technique as a well-established method is limited in terms of pore shape, distribution by its natural or synthetic templates. We combined therefore Replica techniques with additive manufactured (AM) templates to produce foams with a periodic 3D-architecture and modified strut morphologies. Polymeric templates with rectangular/cuboid cells (size = 2.5 × 7.5 mm) were 3D-printed (SLA) with triangular and circular struts and afterwards coated with an alumina slurry. After debinding and sintering, the microstructural properties and mechanical performance were characterized by tomography, SEM, and compression tests compared to a stochastic 30 ppi foam with identical porosity. The AM-derived foams showed a superior compressive strength (>+15%) than the stochastic replica foams. Using barium titanate (BT) AM foams, it has also been observed that the periodic arrangement of the cell structure positively influences the piezoelectric properties and a d33 of 271 pC/N was achieved by a porosity of 59%.

Keywords

• Cellular ceramic
• Replica method
• Additive manufacturing
• Sol-gel coating
• Micro-CT characterization
• Piezoelectric functionalization