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Abstract: A low‐permittivity dielectric ceramic Li2GeO3 was prepared by the solid‐state reaction route. Single‐phase Li2GeO3 crystallized in an orthorhombic structure. Dense ceramics with high relative density and homogeneous microstructure were obtained as sintered at 1000‐1100°C. The optimum microwave dielectric properties were achieved in the sample sintered at 1080°C with a high relative density ~ 96%, a relative permittivity εr ~ 6.36, a quality factor Q × f ~ 29 000 GHz (at 14.5 GHz), and a temperature coefficient of resonance frequency τf ~ −72 ppm/°C. The sintering temperature of Li2GeO3 was successfully lowered via the appropriate addition of B2O3. Only 2 wt.% B2O3 addition contributed to a 21.2% decrease in sintering temperature to 850°C without deteriorating the dielectric properties. The temperature dependence of the resonance frequency was successfully suppressed by the addition of TiO2 to form Li2TiO3 with a positive τf value. These results demonstrate potential applications of Li2GeO3 in low‐temperature cofiring ceramics technology. [ABSTRACT FROM AUTHOR]

Pure ZrB2 powder was Flash sintered in an SPS furnace ( FSPS). The samples were densified up to 95.0% in 35 s under an applied pressure of 16 MPa. Compared to Conventional SPS ( CSPS), the newly developed FSPS technique resulted in an unprecedented energy and time savings of about 95% and 98% respectively. ZrB2 monoliths obtained by CSPS and FSPS were compared with respect to microstructures, densification behavior, and grain growth. The developed methodology might find application to a wide range of highly conductive ceramics as such refractory borides and carbides. [ABSTRACT FROM AUTHOR]

Pure ZrB2 powder was Flash sintered in an SPS furnace ( FSPS). The samples were densified up to 95.0% in 35 s under an applied pressure of 16 MPa. Compared to Conventional SPS ( CSPS), the newly developed FSPS technique resulted in an unprecedented energy and time savings of about 95% and 98% respectively. ZrB2 monoliths obtained by CSPS and FSPS were compared with respect to microstructures, densification behavior, and grain growth. The developed methodology might find application to a wide range of highly conductive ceramics as such refractory borides and carbides. [ABSTRACT FROM AUTHOR]