33results about How to "High Qf value" patented technology

Provided is a composite multilayer ceramic electronic component which is provided with a co-fired low-permittivity ceramic layer and high-permittivity ceramic layer and in which respectively befitting properties are obtained in the low-permittivity ceramic layer and high-permittivity ceramic layer. The low-permittivity ceramic layer (3) and the high-permittivity ceramic layer (4) are constituted of glass ceramics including: a first ceramic comprising MgAl2O4 and / or Mg2SiO4; a second ceramic comprising BaO, RE2O3 (RE being a rare earth element), and TiO2; glass each including 44.0-69.0 wt% of RO (where R is an alkaline earth metal), 14.2-30.0 wt% of SiO2, 10.0-20.0 wt% of B2O3, 0.5-4.0 wt% of Al2O3, 0.3-7.5 wt% of Li2O, and 0.1-5.5 wt% of MgO; and MnO; the content ratios of the glass and the like in the low-permittivity ceramic layer (3) and the high-dielectric constant ceramic layer (4) being different from each other.

The invention discloses a microwave dielectric ceramic with middle permittivity and ultralow dielectric loss, and a preparation method and application thereof. The microwave dielectric ceramic is characterized in that the chemical expression formula is Sr2(Ti1-xZrx)O4, wherein x is more than 0 and less than 0.1. The preparation method of the microwave dielectric ceramic comprises the following steps: preparing SrCO3, TiO2 and ZrO2 on the basis of the stoichiometric ratio in the chemical expression formula; performing continuous ball milling for 24h; then drying; screening; roasting the prepared powder for 1-3h under the temperature of 1200-1250; performing secondary ball milling; screening; pressing the prepared powder into a blank; and roasting for 1-3h under the temperature of 1475 to 1550 DEG C to obtain a ceramic block. According to the preparation method, the outstanding permittivity and quality factor combination of the prepared Sr2(Ti0.975Zr0.025)O4 ceramic is superior to thoseof other microwave dielectric material systems, so that the microwave dielectric ceramic can be widely applied to elements of wireless communication equipment, such as a microwave resonator and a microwave filter; and the microwave dielectric ceramic is extremely high in application value in the fields of base station communication and satellite communication.

The invention belongs to the field of electronic ceramics and its manufacture, and in particular relates to a low-temperature sintered composite microwave dielectric ceramic material and a preparation method thereof. The material is composed of BaO‑ZnO‑TiO with a mass percentage of 91% to 99%. 2 The material and the fever reducer are composed of 1% to 9% by mass, and the material of the invention can be obtained through solid phase reaction. BaO‑ZnO‑TiO 2 The composition of the material is BaZn 2 Ti 4 o 11 ‑xTiO 2 (x=1wt%-10wt%); The manufacture raw material of fever reducer is: Li 2 CO 3 , SiO 2 , B 2 o 3 , ZnO, La 2 o 3 , MnCO 3 、BaCO 3 . Its sintering temperature is 850 ℃ ~ 900 ℃, and the dielectric constant is adjustable from 24 to 26, the quality factor Qf is high > 30000 GHz, and the loss is low ≤ 10 ‑4 , The temperature coefficient of resonant frequency is stable near zero-5ppm / ℃~5ppm / ℃, and does not react with silver paste. It is suitable for low-temperature and high-permittivity microwave dielectric core materials in microwave devices such as dielectric resonators, filters, and oscillators in LTCC systems and satellite communications.

The present invention discloses a preparation method of low-temperature synthetic single-phase nano CaTiO3 ceramic powder body by using sol-gel process. Said method includes the following steps: dissolving inorganic salt of calcium in anhydrous ethyl alcohol; dissolving butyl titanate in the mixed solution of anhydrous ethyl alcohol and acetic acid; drop-adding nitric acid and acrylic acid to regulate pH value; according to mole ratio of 1:1 of calcium: titanium mixing the above-mentioned two solutions, adding proper quantity of dispersing agent; uniformly stirring the obtained solution, sealing and standing still to obtain gel, drying and grinding said gel, calcining so as to obtain the invented nano ceramic powder body.

The invention provides a ZMAT series microwave ceramic material and a preparation method thereof, which relate to the field of information functional materials. The ceramic material includes a main crystal phase and modified additives, and the main crystal phase includes a main material and an auxiliary material. The general chemical formula of the main crystal phase is Mg 2 sn x Si 5+2x Al 4‑ 4x o 18 ·aZr 1‑3y La 4y TiO 4 , where 0.05 <x<0.1，0.1<y<0.3，0.01<a<0.05。其中mg2Sn x Si 5+2x al 4‑4x o 18 The general chemical formula of the main material, Zr 1‑3y La 4y TiO 4 The general chemical formula of the auxiliary material. The mass fraction of the main crystal phase in the ceramic material is 98-99.5 wt%, and the mass fraction of the modification additive in the ceramic material is 0.5-2 wt%. Modified additives are selected from SrCO 3 、BaCO 3 、TiO 2 , Nb 2 o 5 , Sb 2 o 3 and MnCO 3 One or more mixtures of these. Ceramic material of the present invention is a kind of lead-free environment-friendly material, and it adopts solid phase method to synthesize main material Mg 2 sn x Si 5+2x al 4‑4x o 18 and auxiliary material Zr 1‑3y La 4y TiO 4 , to prepare a uniform powder ceramic material. After the powder is sintered, the room temperature dielectric constant is between 5 and 8, the Qf value is ≥60000GHz, and the temperature coefficient τf (-40~85℃): ±10ppm / ℃ microwave ceramics The material meets the relevant microwave performance requirements of microwave devices.