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Best synthetic Mg 2 TiO 4 -based ceramics for the study, research Mg 2 TiO 4 methods and regulation by different additives Mg 2 TiO 4 -based ceramics τ f , to obtain the τ f nearly 0, microwave dielectric ceramics for microwave communication. First, using traditional solid-phase synthesis prepared Mg 2 TiO 4 Research calcining temperature and MgO powder and sintering behavior and microwave dielectric burn after heat treatment at 1100 ℃ electrical performance impact. Optimum calcining temperature of 1190 ℃, the sintered Mg 2 TiO 4 ceramic porous ceramics, and MgO are not heat-treated of Mg 2 TiO 4 activity increased help to lower the sintering temperature and microwave dielectric properties. Not heat-treated MgO, 1190 ℃ synthetic Mg 2 TiO 4 matrix for Mg 2 TiO 4 - CaTiO 3 ceramics sintered difficult as porcelain features by adding the second low melting point oxides ZnNb 2 O 6 explore ZnNb 2 O 6 and CaTiO 3 two additives of Mg 2 TiO 4 ceramic phase component, the impact of the morphology and microwave dielectric properties, and successfully improved ceramic sintering characteristics. The study found that adding a small amount of ZnNb 2 O 6 increase the Mg 2 the the TiO 4 -CaTiO 3 ceramic density, εr and Q × f, and reduce the τ f . Add SrTiO 3 Mg 2 TiO 4 sintering, the adjust τ f but prepared Mg 2 TiO 4 -SrTiO 3 ceramic εr too low, not suitable for practical use. Therefore choose to have a high quality factor and τ f Ca0.8Sr0.2TiO 3 to adjust the Mg 2 the TiO 4 ceramics τ f . 2 the (Mg 0.09 Co 0.01 ) the TiO 4 -Ca0.8Sr0.2TiO 3 system found in Ca / Sr deviate from the 4, close to 3, the reason for the deviation needs to be further explored. And the Mg 2 the TiO 4 grain easily with the increase of the sintering temperature grow rapidly, resulting in system εr increasing at high temperatures, the Q × f value and τ f values ??decline, τ f values ??decline requires further analysis. In Mg 2 TiO 4 adding Co to improve the of Mg 2 of TiO 4 of the base material permittivity, select high quality factor Ca 0.8 Sm 0.4 / 3 TiO 3 to adjust (Mg 0.09 Co 0.01 ) 2 TiO 4 of τ f values. In the presence of (Mg 0.09 Co 0.01 ) 2 TiO 4 , Ca 0.8 Sm 0.4 / 3 TiO 3 , (Mg . 0.09 Co 0.01 ) TiO 3 Three-phase, there are still more pores, but the smaller the grain size of the ceramic, and no (Mg 0.09 Co 0.01 ) 2 TiO 4 phenomenon of grain is easy to grow up, so get a good microwave dielectric properties. At the same time, the system τ f values ??from the sintering temperature impact, with the increase in the sintering temperature, grain growth, porosity decreases, the the εr slow increase of the ceramic, Q × f value increased first and then decreased trend.
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