研究了Nd3+离子A位置换改性(Pb0.5Ca0.5)(Fe0.5Nb0.5)O3陶瓷的微波介电性能.[(Pb0.5Ca0.5)1-xNdx](Fe0.5Nb0.5)O3(PCNFN)陶瓷的微波介电性能得到改善是由于少量过剩的Nd3+与(Pb,Ca)2+的固溶能够消除氧空位.当x=0.02时,能够形成单相的钙钛矿相,随着Nd3+置换量的增加,过剩的Nd3+将导致第二相焦绿石的形成,焦绿石会恶化PCNFN的微波介电性能.PCNFN介电性能随x的增加而下降是由于焦绿石相随x增加的结果.当x=0.02-0.05,PCNFN陶瓷有很好的微波介电性能,介电常数K>100,Qf值为5385-5797GHz,频率温度系数TCF随Nd3+含量的增加从正的变为负的.
Microwave dielectric properties of A-site substitution by Nd3+ in (Pb0.5Ca0.5)(Fe0.5Nb0.5)O3 system were investigated.
Microwave dielectric properties of [(Pb0.5Ca0.5)1-xNdx](Fe0.5Nb0.5)O3 (PCNFN) were improved because the solid solution of small amount of surplus Nd3+
with (Pb,Ca)2+ could eliminate oxygen vacancies. A single perovskite phase was formed when x=0.02. Surplus Nd3+ resulted in the formation of secondary
phase (pyrochlore), which can deteriorate to the microwave dielectric properties of PCNFN ceramics. The decreasing of dielectric properties with x content was
mainly caused by the formation of pyrochlore. Dielectric constant was above 100 and quality factor Qf values were 5385～5797GHz as x=0.02～0.05. Temperature
coefficient of resonant frequency (TCF) was changed from positive to negative with the increase of x content.
参考文献
| [1] | Kato J, Kagata H, Nichimoto K. Jpn. J. Appl. Phys., 1991, 30: 2343--2346. [2] Kato J, Kagata H, Nichimoto K. Jpn. J. Appl. Phys., 1992, 31: 3144--3147. [3] Kagata H, Kato J, Nichimoto K, et al. Jpn. J. Appl. Phys., 1993, 32: 4332--4334. [4] Kucheiko S, Choi J W, Kim H J, et al. J. Am. Ceram. Soc., 1997, 80(11): 2937--2940. [5] Kim I S, Jung W H, Inaguma Y, et al. Mater. Res. Bull., 1995, 30(3): 307--316. [6] Yoshida M, Hara N, Takada T, et al. Jpn. J. Appl. Phys., 1997, 36: 6816--6823. [7] Kim W S, Kim E S, Yoon K H. J. Am. Ceram. Soc., 1999, 82(8): 2111--2115. [8] 杨秋红, 金应秀, 徐军(Yang Qiu-Hong, et al). 硅酸盐学报(Journal of the Chinese Ceramic Society), 2002, 30(5): 554--558. [9] Michiura N, Tatekawa T, Higuchi Y, et al. J. Am. Ceram. Soc., 1995, 78(3): 793--796. [10] Shannon R D. J. Appl. Phys., 1993, 73(1): 348--366. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%