Plate like BNT templates were synthesized from BiT platelets
The TGG method was used to produce the textured piezoceramics. The BNT–BT–AN ceramic powders (50 wt.%) were mixed with 6.5 wt.% binder (polyvinyl alcohol, Butvar B-98, molecular weight 40000–70000, Sigma–Aldrich), 35 wt.% solvents (a mixture of butanone and ethanol with 2:3 weight ratio, Alfa Aesar), 6.5 wt.% plasticizers (polyethylene glycol and dibutyl phthalate with 1:1 weight ratio, Alfa Aesar), and 2.0 wt.% dispersant (triethanolamine, Sigma–Aldrich) in order to produce a slurry. After ultrasonically mixing (UP200S, Hielscher Ultrasonics, Stuttgart, Germany), the BNT templates mixed with corresponding BT and AN starting powders were added to the slurry and mixed by magnetic stirring for 2 h. The resulting slurry was BMS-303141 on plastic tape (Laufenberg GmbH, Krefeld, Germany) by a doctor blade with 200 μm thickness. After drying at room temperature, the green tapes were punched, stacked (around 40 layers) and finally laminated at 60 °C with uniaxial pressure of 50 MPa into disk samples. The green samples were heated to 550 °C with ramping rate of 0.2 K/min and kept for 2 h to burn out the binder. After reptiles the samples were cold-isostatically pressed at 300 MPa (KIP 100 E, Paul-Otto Weber GmbH, Remshalden, Germany) and followed by sintering in air at 1150 °C for 6 h in covered alumina crucibles. To minimize the loss of volatile elements, samples were covered with an atmospheric powder of the same composition. For preparation of randomly oriented counterparts, disk-shaped samples of 10 mm in diameter and 1 mm in thickness were uniaxially compacted by hand, followed by cold isostatic pressing at 300 MPa. Sintering was performed for both textured and untextured samples together. The relative densities for the randomly oriented and textured samples determined by the Archimedes method were 97.3% and 92.6%, respectively.