TY - JOUR
T1 - Properties of Y2Ti2O7 based microwave dielectric ceramics doped with lead titanate
AU - Ding, Jiayu
AU - Xiao, Yuan
AU - Zhang, Qitu
PY - 2010/11
Y1 - 2010/11
N2 - A new kind of Y2Ti2O7 microwave dielectric ceramics with middle dielectric constant was studied with an addition of lead titanate. The properties were characterized and measured by X-ray diffraction, scanning electron microscopy, network analyzer and impedance analyzer. The phase composition and dielectric properties of ceramics doped with PbTiO3 were investigated. The results showed that the main phase of PbTiO3 doped ceramics did not change and still exhibited a kind of pyrochlore structure. It could be speculated that PbTiO3 came into the Y2Ti2O7 crystal lattice. Pb2+ was incorporated into Y3+ site on the A site of pyrochlore structure, which also lead to the formation of a new kind of vacancy defects. The lattice diffusion rates increased due to the breaking of order in the structure, so the sintering temperature was effectively decreased. As a small amount of Pb elements was added, the lattice constant increased, the volume of unit cell became larger, the Ti4+ ions had more space to move, the total polarization of the materials increased, thereby the dielectric properties were enhanced, in particular, the value of dielectric constant slightly increased. When the amount of lead titanate was 2%, Y2Ti2O7 ceramics sintered at 1345°C, exhibited better dielectrical properties: εr=56.4, tan δ=1.21×10-3, Q×f=4776 GHz.
AB - A new kind of Y2Ti2O7 microwave dielectric ceramics with middle dielectric constant was studied with an addition of lead titanate. The properties were characterized and measured by X-ray diffraction, scanning electron microscopy, network analyzer and impedance analyzer. The phase composition and dielectric properties of ceramics doped with PbTiO3 were investigated. The results showed that the main phase of PbTiO3 doped ceramics did not change and still exhibited a kind of pyrochlore structure. It could be speculated that PbTiO3 came into the Y2Ti2O7 crystal lattice. Pb2+ was incorporated into Y3+ site on the A site of pyrochlore structure, which also lead to the formation of a new kind of vacancy defects. The lattice diffusion rates increased due to the breaking of order in the structure, so the sintering temperature was effectively decreased. As a small amount of Pb elements was added, the lattice constant increased, the volume of unit cell became larger, the Ti4+ ions had more space to move, the total polarization of the materials increased, thereby the dielectric properties were enhanced, in particular, the value of dielectric constant slightly increased. When the amount of lead titanate was 2%, Y2Ti2O7 ceramics sintered at 1345°C, exhibited better dielectrical properties: εr=56.4, tan δ=1.21×10-3, Q×f=4776 GHz.
KW - Doping
KW - Lead titanate
KW - Microwave dielectric ceramics
KW - Pyrochlore structure
UR - http://www.scopus.com/inward/record.url?scp=78650563011&partnerID=8YFLogxK
U2 - 10.3969/j.issn.0258-7076.2010.06.017
DO - 10.3969/j.issn.0258-7076.2010.06.017
M3 - 文章
AN - SCOPUS:78650563011
SN - 0258-7076
VL - 34
SP - 875
EP - 879
JO - Xiyou Jinshu/Chinese Journal of Rare Metals
JF - Xiyou Jinshu/Chinese Journal of Rare Metals
IS - 6
ER -