resumo
An innovative approach for fabricating pillar arrays for ultrasonic transducer applications is disclosed. It involves the preparation of concentrated piezoelectric lead zirconate titanate (PZT) suspensions in aqueous solutions of epoxy resin and its polymerization upon adding a polyamine based hardener. Zeta potential and rheological measurements revealed that 1 wt.% dispersant, 20 wt.% of epoxy resin and a hardener/epoxy resin ratio of 0.275 mL g(-1), were the optimized contents to obtain strong PZT samples with high green strength (35.21 +/- 0.39 MPa). Excellent ellipsoidal and semi-circle shaped pillar arrays presenting lateral dimensions lower than 10 mu m and 100 mu m height were successfully achieved. The organics burning off was conducted at 500 degrees C for 2 h at a heating rate of 1 degrees C min(-1). Sintering was then carried out in the same heating cycle at 1200 degrees C for 1 h. The microstructures of the green and sintered ceramics were homogeneous and no large defects could be detected. (C) 2011 Elsevier Ltd. All rights reserved.
palavras-chave
EPOXY-RESIN; GELLING AGENT; ALUMINA; CERAMICS
categoria
Materials Science
autores
Olhero, SM; Garcia-Gancedo, L; Button, TW; Alves, FJ; Ferreira, JMF
nossos autores
José Maria da Fonte Ferreira
Professor(a) Jubilado(a)
Susana Maria Henriques Olhero
Professor AuxiliarProjectos
Development of microelectromechanical systems by gelcasting - GELMEMS (PTDC/CTM/099489/2008)
agradecimentos
S.M. Olhero wishes to thank to Foundation for Science and Technology of Portugal for the financial support under the grant SFRH/BPD/27013/2006. The authors would also like to thank CICECO for the work at the University of Aveiro and FCT for the financial support under the project PTDC/CTM/099489/2008. The support of EPSRC for the work at the University of Birmingham (and the associated design of the moulded structures by Drs. C. Demore and S. Cochran at the University of Dundee) is also gratefully acknowledged. The authors would also like to thank C. Meggs at the University of Birmingham for his input into the work.