Premium
Sodium Bismuth Titanate‐Based Lead‐Free Piezoceramics Prepared by Aqueous Gelcasting
Author(s) -
Zhou Dongxiang,
Li Hui,
Gong Shuping,
Hu Yunxiang,
Han Ke
Publication year - 2008
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2008.02511.x
Subject(s) - materials science , aqueous solution , scanning electron microscope , ammonium persulfate , microstructure , ceramic , persulfate , composite material , chemical engineering , micrograph , dielectric , piezoelectricity , nuclear chemistry , mineralogy , chemistry , organic chemistry , engineering , polymerization , polymer , catalysis , optoelectronics
Aqueous gelcasting for 0.94Bi 0.5 Na 0.5 TiO 3 –0.06BaTiO 3 (BNBT6) lead‐free piezoceramics was investigated in this paper. A stable BNBT6 suspension with 50 vol% of solid loading and <1Pa·s of viscosity was successfully prepared when 0.5 wt% of PMAA‐NH 4 was added with the pH value controlled in the range 8–10. Dehydration and desiccation of the gelled parts could be controlled easily through dipping pretreatment with a 5 wt% ammonium persulfate solution for 24 h or with a 10 wt% ammonium persulfate solution for 12 h. Scanning electron microscopy micrographs show that the BNBT6 ceramic prepared by the gelcasting route exhibits a homogeneous microstructure and a high density. Optimal piezoelectric and dielectric properties were obtained: d 33 =132pC/N , , tg δ=0.019, and k p =0.25.