Microwave dielectric properties and sintering behavior of nano-scaled (α plus θ)-Al2O3 ceramics

被引：18

作者：

Huang, Cheng-Liang ^{[1
]}

Wang, Jun-Jie ^{[1
]}

Yen, Fu-Su ^{[2
]}

Huang, Chi-Yuen ^{[2
]}

机构：

[1] Natl Cheng Kung Univ, Dept Elect Engn, Tainan 70101, Taiwan

[2] Natl Cheng Kung Univ, Dept Resources Engn, Tainan 70101, Taiwan

来源：

MATERIALS RESEARCH BULLETIN | 2008年 / 43卷 / 06期

关键词：

ceramics; oxides; crystal growth; dielectric properties;

D O I：

10.1016/j.materresbull.2007.06.032

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The dielectric properties at microwave frequencies and the microstructures of nano (alpha + theta)-Al2O3 ceramics were investigated. Using the high-purity nano (alpha + theta)-Al2O3 powders can effectively increase the value of the quality factor and lower the sintering temperature of the ceramic samples. Grain growth can be limited with theta-phase Al2O3 addition and high-density alumina ceramics can be obtained with smaller grain size comparing to pure alpha-Al2O3. Relative density of sintered samples can be as high as 99.49% at 1400 degrees C for 8 h. The unloaded quality factors Q x f are strongly dependent on the sintering time. Further improvement of the Q x f value can be achieved by extending the sintering time to 8 h. A dielectric constant (Er) Of 10, a high Q x f value of 634,000 GHz (measured at 14 GHz) and a temperature coefficient of resonant frequency (tau(f)) of -39.88 ppm/degrees C were obtained for specimen sintered at 1400 degrees C for 8 h. Sintered ceramic samples were also characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). (C) 2007 Elsevier Ltd. All rights reserved.

引用

页码：1463 / 1471

页数：9

共 12 条

[1] Sintered alumina with low dielectric loss [J].

Alford, NM ;

Penn, SJ .

JOURNAL OF APPLIED PHYSICS, 1996, 80 (10) :5895-5898

[2] ANALYSIS AND EVALUATION OF A METHOD OF MEASURING COMPLEX PERMITTIVITY AND PERMEABILITY OF MICROWAVE INSULATORS [J].

COURTNEY, WE .

IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, 1970, MT18 (08) :476-&

[3]

Hakki B. W., 1960, IEEE Trans. Microwave Theory Techn, V8, P402, DOI DOI 10.1109/TMTT.1960.1124749

[4]

HIRNO SI, 1991, J AM CERAM SOC, V74, P1320

[5] Sintering behavior and microwave dielectric properties of nano alpha-alumina [J].

Huang, CL ;

Wang, JJ ;

Huang, CY .

MATERIALS LETTERS, 2005, 59 (28) :3746-3749

[6]

KAKADA T, 1994, J AM CERAM SOC, V77, P1909

[7]

KAKADA T, 1994, J AM CERAM SOC, V77, P2485

[8]

NISHIGAKI S, 1987, AM CERAM SOC BULL, V66, P1405

[9]

REED JS, 1995, PRINCIPLES CERAMICS, P219

[10] EFFECT OF GLASS ADDITIONS ON BAO-TIO2-WO3 MICROWAVE CERAMICS [J].

TAKADA, T ;

WANG, SF ;

YOSHIKAWA, S ;

JANG, SJ ;

NEWNHAM, RE .

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 1994, 77 (07) :1909-1916

← 1 2 →