44results about How to "High quality factor Qf" patented technology

The invention discloses temperature-stable type ultralow-dielectric-constant dielectric ceramic InAlMg6O9 and a preparation method thereof. The preparation method comprises: (1) weighing original powders of In2O3, Al2O3 and MgO with the purity of 99.9 wt% or more according to the formula of InAlMg6O9 and proportioning; (2) performing wet-type ball milling mixing on the raw materials of the step (1) for 12 h by selecting distilled water as a ball milling medium, baking and pre-burning at 1300 DEG C in atmosphere for 6 h; and (3) adding a binder into the powder prepared in the step (2) and granulating, then performing compression molding, and finally sintering at 1350-1400 DEG C in atmosphere for 4 h, wherein the binder employs a polyvinyl alcohol solution with the mass concentration of 5% and the addition amount of polyvinyl alcohol is 3% by mass of the total powder. The prepared ceramic has good sintering, has the dielectric constant up to 6.9-7.5, has the quality factor Qf up to 149000-194000 GHz, has a small resonant-frequency temperature coefficient, and has extremely great application value in industry.

The invention discloses ultralow dielectric constant microwave dielectric ceramic Li3BiW8O27 capable of performing low-temperature sintering and a preparation method of the ultralow dielectric constant microwave dielectric ceramic Li3BiW8O27. The preparation method comprises the following steps: (1) weighing and dosing the original powder, having the purity more than 99.9wt%, of Li2CO3, Bi2O3 and WO3 according to the composition of Li3BiW8O27; (2) performing wet ball-milling on the raw material in the step (1), mixing for 12 hours, wherein the ball-milling medium is distilled water, and pre-sintering in the atmosphere at the temperature of 650 DEG C after drying; and (3) adding an adhesive into the powder prepared in the step (2), granulating, performing compression molding, and finally sintering in the atmosphere at the temperature of 700-730 DEG C, wherein the adhesive refers to 5% polyvinyl alcohol solution, and the addition amount of polyvinyl alcohol accounts for 3 percent of the total mass of the powder. The ceramic prepared by the invention has high sintering property at the temperature of 700-730 DEG C and has extremely high application values in the industry, the dielectric constant of the ceramic is 7.6-8.3, the quality factor Qf value reaches 54000-71000GHz, and the resonant frequency temperature coefficient is low.

The invention discloses temperature stable ultra-low dielectric constant microwave dielectric ceramic BaBi2W6O22 which can be sintered at low temperature and a preparation method thereof. The method comprises the following steps: (1) weighing the following original powder with purity of over 99.9wt%: BaCO3, Bi2O3 and WO3 according to the composition of BaBi2W6O22; (2) mixing the raw materials in the step (1) by wet grinding for 12 hours by adopting distilled water as the grinding medium, baking, and pre-burning in the atmosphere at 700 DEG C for 6 hours; (3) adding a binder into the powder prepared in the step (2), granulating, pressing and forming, and sintering in the atmosphere at 750-780 DEG C for 4 hours, wherein the binder is prepared from polyvinyl alcohol solution with mass concentration of 5 percent, and the additive amount of polyvinyl alcohol is 3 percent of the total mass of the powder. The ceramic prepared by the method is well sintered at 750-780 DEG C, has the dielectric constant being 17.8-18.4 and the quality factor Qf value being up to 55000-67000GHz, has a small temperature coefficient of resonance frequency, and has a great application value in the industry.

The invention discloses a low-temperature sintering temperature-stable microwave dielectric ceramic ZnY3VO8 with an ultralow dielectric constant and a preparation method of the microwave dielectric ceramic ZnY3VO8. The preparation method comprises the following steps of (1) weighing initial powder of ZnO, Y2O3 and V2O5 according to the composition of ZnY3VO8, and proportioning, wherein the purities of ZnO, Y2O3 and V2O5 are larger than 99.9wt%; (2) carrying out wet-type ball milling on the raw materials in the step (1) by virtue of distilled water serving as a ball milling medium, mixing for 12 hours, and presintering in an atmospheric environment with the temperature of 900 DEG C for 6 hours after drying; and (3) adding an adhesive in the powder prepared in the step (2), granulating, then, carrying out compression molding, and finally, sintering in an atmospheric environment with the temperature of 950-990 DEG C for 4 hours, wherein the adhesive is a polyvinyl alcohol solution with the mass concentration of 5%, and the additive amount of polyvinyl alcohol accounts for 3% of the total mass of the powder. The ceramic prepared by using the preparation method can be favorably sintered at the temperature of 950-990 DEG C, has the dielectric constant of 7.3-7.9 and is high in quality factor Qf value up to 73000-96000GHz and small in temperature coefficient of resonance frequency so as to have an extremely high application value in industry.

The invention discloses low-temperature sinterable temperature-stable type microwave dielectric ceramic Ca3Y4V2O14 having a low dielectric constant and a preparing method thereof. The method includes: (1) weighing original powder having purity higher than 99.9% (that is a weight percentage) of CaCO3, Y2O3 and V2O5 according to constitution of the Ca3Y4V2O14 and blending; (2) subjecting the raw materials in the step (1) to wet ball milling and mixing for 12 h, with a ball milling medium being distilled water, drying, and pre-sintering at 820 DEG C in an atmosphere of air for 6 h; and (3) adding an adhesive into the powder prepared in the step (2), granulating, performing compression moulding, and sintering at 870-920 DEG C in the atmosphere of air for 4 h, wherein the adhesive adopts a polyvinyl alcohol solution having a mass concentration of 5%, and the adding amount of the polyvinyl alcohol is 3% of the total mass of the powder. The ceramic prepared by the method is good in sintering performance at 870-920 DEG C, the dielectric constant of the ceramic is 25.4-26.3, the quality factor Qf of the ceramic is 49000-63000 GHz, and the temperature coefficient of resonance frequency of the ceramic is small. The ceramic has high application value in the industry.