Dielectric Properties and Sintering Characteristics of CaTiO3-(Li1/2Nd1/2)TiO3 Ceramics

Abstract

The dielectric properties and the sintering effect upon microstructure of (1 − x) CaTiO 3 -x(Li 1/2 Nd 1/2 )-TiO 3 Ceramics are investigated in this paper. Nd 3+ and Mg 2+ ions co-substitution for Ca 2+ on A site improves the sintering characteristic of CaTiO 3 ceramics with forming orthorhombic perovskite structure. The structure of (1 − x) CaTiO 3 -x(Li 1/2 Nd 1/2 )TiO 3 changes from orthorhombic to tetragonal as (Li 1/2 Nd 1/2 )TiO 3 addition increasing. Limited solubility of (Li 1/2 Nd 1/2 )TiO 3 in CaTiO 3 forming a part solid solution compound achieves the adjustment of τ ε for CaTiO 3 at low sintering temperature. The proper dielectric properties with ε = 78, tan δ = 0.0006, τ ε = +7 ppm/ • C are obtained for 0.8Ca 0.67 (Nd,Mg) 0.22 TiO 3 -0.2(Li 1/2 Nd 1/2 )TiO 3 ceramics.

Calcium titanate ceramics obtained by combustion synthesis and two-step sintering

“…6(a-e)). These results were consistent with previous reports [22,31,38,40] that the charge polarization (or relaxation polarization) of simply processed structurally dense materials with fewer pores produced a lager dielectric constant. In addition, at 200 kHz, the dielectric loss of calcium titanate ceramics sintered in different sintering conditions was low, ranging from 0.02 to 0.06 ( Fig.…”

“…The dielectric constant of the TSS4 sample, produced at T 2 of 1250 °C, was the highest at 110. The dielectric constant of the TSS4 sample at 200 kHz was greater than the ε r (∼83) of a similar ceramic reported in other researches [23,38]. The improved dielectric properties of the sintered ceramics were attributed to increased densification and reductions in porosity [39] (see Fig.…”

Effect of γ-Irradiation on the Dielectric and Conductivity Properties of Nano-Wollastonite

“…The latter plays an important part at higher frequencies. Microstructure difference, morphotropic phase boundary, pores, defects, and so forth are the main sources of the relaxation polarization, but they do not work at higher frequencies [11].…”

Effects of (Li0.5Nd0.5)2+ on the phase evolution, Raman spectra and microwave dielectric properties in CaO–Nd2O3–TiO2 ceramic

“…The OST of samples at x = 0, 0.2, and 0.4 were 1375 • C, 1300 • C and 1250 • C, respectively. On the one hand, the OST of pure Li 0.5 Nd 0.5 TiO 3 ceramic was about 1250 • C [31]. On the other hand, Li 2 CO 3 was suggested as a promising sintering aid for densification at relatively low sintering temperatures [32].…”