Compositional Design of Zirconium Titanate Solid Solution for Microwave Dielectric Material and Low Expansive Material
Grant-in-Aid for General Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Tokyo Institute of Technology|
FUKUNAGA Osamu Tokyo Institute of Technology, Faculty of Engineering, Professor, 工学部, 教授 (20199251)
URABE Kazuyori Ryukoku University, Faculty of Material Chemistry, Professor, 理工学部, 教授 (50016383)
IKAWA Hiroki Tokyo Institute of Technology, Faculty of Engineering, Associate Professor, 工学部, 助教授 (30016612)
|Project Period (FY)
1989 – 1990
Completed(Fiscal Year 1990)
|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1990 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1989 : ¥1,500,000 (Direct Cost : ¥1,500,000)
|Keywords||Microwave dielectric material / Paraelectric / Zirconium titanate / alpha-PbO_2 structure / Thermal expansion / Compositional design / ZrTiO_4 / HfTiO_4 / α-PbO_2型化合物 / 低熱膨張 / 高周波用誘電体|
1. Dielectric Property of Solid Solutions in the ZrTiO_4-HfTiO_4 System
Well sintered pellets of end compositions and solid solutions were suffered from either of the following two heat treatment. Those two were quenching in air after heating at 1300^ﾟC (abbreviated as quenched sample) and slow furnace cooling to 900^ﾟC after heating at 1200^ﾟ (abbreviated as cooled sample). Dielectric properties -- relative permittivity (K') at 1 kHz and GHz, temperature coefficient of capacitance (TCC), coefficient of dielectric loss (tan delta), and temperature coefficient of resonance frequency (TCR) -- of quenched and cooled samples were measured. Results are summarized as follow.
(1) Realative permittivity of the quenched sample decreased almost linearly with increasing Hf content.
(2) The composition vs. K' relation of the cooled sample was different significantly from that of the quenched sample taking a peak value of K' at Zr_<0.75>Hf_<0.25>TiO_4.
(3) The composition vs. TCC relations of the quenc
hed and cooled samples were similar to those written in (1) and (2), respectively.
2. Dielectric Property of Solid Solutions in the ZrTiO_4-SnO_2 System
A research analogical to that mentioned in 1. was made to this system also, and resembling respective relations to (1), (2), and (3) were found. These coincidence is that predicted by the working hypothesis on this compound. Accordingly, a new composition of microwave dielectric resonator was presented. Further, the hypothesis which is powerful to predict the phase transformation and thermal expansion, has been revealed might be effective to explain dielectric properties of these compounds.
3. Design of Low Expansive Composition by the Working Hypothesis
Phase transformations and thermal expansion properties were investigated for compounds in systems ZrTiO_4-In_2O_3-Sb_2O_5 and ZrTiO_4-In_2O_3-Ta_2O_5. The thermal expansions of ZrTi_<0.2>In_<0.4>Ta_<0.4>O_4 and ZrTi0.1In0.45Ta0.4504 were found smaller than that of HfTi04. Further, the fact was that predicted by the hypothesis. Less
Research Output (16results)