The shrinking process and microwave dielectric properties of BaCu(B2O5)-added 0.85BaTi4O9–0.15BaZn2Ti4O11 ceramics
2015; Elsevier BV; Volume: 66; Linguagem: Inglês
10.1016/j.materresbull.2015.02.023
ISSN1873-4227
AutoresBin Tang, Guodong Xia, Shengquan Yu, Zixuan Fang, Shuren Zhang,
Tópico(s)Advanced ceramic materials synthesis
ResumoThe effect of BaCu(B2O5) (BCB2) addition on the shrinking process and microwave dielectric properties of 0.85BaTi4O9–0.15BaZn2Ti4O11 (BZT) ceramics were investigated by the conventional solid-state ceramic route. Adding BaCu(B2O5) into 0.85BaTi4O9–0.15BaZn2Ti4O11 ceramics led to the formation of two new phases: Ba4Ti13O30 and BaTi(BO3)2. The densification of the 5–15 wt% BaCu(B2O5) + BaTi4O9–BaZn2Ti4O11 ceramics sintered at approximate 900 °C for 2 h was attributed to the liquid phase sintering mechanism formed by the meltdown of BaCu(B2O5). The addition of BaCu(B2O5) also increased the shrinkage rate and promoted the grain growth. Because of the improved densification, the dielectric constant of the samples sintered at 900 °C was increased from 29.5 to 32.2 with increasing BCB2 from 5 wt% to 15 wt%. However, the Q × f value decreased sharply from 27,600 GHz to 15,900 GHz due to the progressively increased Ba4Ti13O30 as well as the whisker glass phase. At last, good microwave dielectric properties with values of ϵr = 30.9, Q × f = 20,200 GHz and τf = +11.7 ppm/°C were obtained in the BZT ceramics with 11 wt% BCB2 sintered at 900 °C for 2 h. It was suitable for the low temperature co-fired ceramics (LTCC) applications.
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