Sinterability improvement of Ba(Mg1/3Ta2/3)O3 dielectric ceramics

The sinterability of Ba(Mg_1/3Ta_2/3)O₃ ceramics synthesized by solid-state-reaction methods was investigated. The poor sinterability of the present ceramics was found to be primarily due to the presence of satellite secondary phases of Ba₅Ta₄O₁₅ and Ba₄Ta₂O₉, and the nearly complete densification of Ba(Mg_1/3Ta_2/3)O₃ ceramics was accomplished successfully by controlling the phase constitution of the calcined powders. For this purpose, enhanced ball-milling processes were found to be extremely effective. Moreover, excellent microwave dielectric characteristics (_r = 24.5–24.7, Q = 26 000 at 9.8 GHz, and _f = 1.7 p.p.m. C^–1) were attained in the dense Ba(Mg_1/3Ta_2/3)O₃ ceramics without additives.