37 results about "Microwave dielectric properties" patented technology

The invention relates to the technical field of recycled asphalt mixture recovery, in particular to a mixing uniformity monitoring method adaptive to a recycled asphalt mixture, which comprises the following steps: S101, performing time-space fusion on infrared thermal radiation field dynamic capture and microwave dielectric property synchronous monitoring bimodal sensing to jointly perform mixing defect alarm; s102, based on the dynamic sequence of the infrared thermal radiation field, judging the particle motion consistency through the standard deviation of the motion direction angle, integrating the infrared temperature field and microwave dielectric data, constructing a three-dimensional feature vector, comprehensively evaluating the uniformity through a weighting function, judging defects according to the maximum contribution term, and generating an optimization instruction; and S103, setting a grading standard based on the multi-modal features, and feeding back and adjusting the process according to a grading result. According to the invention, infrared thermal radiation and microwave dielectric characteristics are combined, temperature uniformity and material component distribution are evaluated synchronously, and the problem of monitoring that the thermal uniformity of the recycled asphalt is not equal to the component uniformity is solved.

The invention belongs to the field of microwave dielectric ceramic materials, and particularly provides a method for improving the performance of zinc aluminate microwave ceramic based on an LBSCA (Li2O-B2O3-SiO2-CaO-Al2O3) composite sintering aid, so that the prepared zinc aluminate microwave dielectric ceramic material has a low dielectric constant and a high thermal expansion coefficient, and is suitable for manufacturing a ceramic substrate with excellent performance. According to the invention, a Zn < 0.90 > Co < 0.10 > Al < 2 > O < 4 > system is adopted, an LBSCA (Li2O-B2O3-SiO2-CaO-Al2O3) composite sintering aid is introduced, and sintering and dielectric properties are optimized through a plurality of mechanisms. The doping of the LBSCA glass has obvious influence on the microstructure and density of the ceramic, and the microwave dielectric property of the ceramic is further improved. According to the invention, when the sintering temperature is 1175 DEG C and x is equal to 1.5 wt%, the optimal performance is as follows: epsilon r is equal to 5.25, Q * f is equal to 7334 GHz, and tauf is equal to-25.18 ppm / DEG C; the CTE value is the maximum value of 11.18 ppm / DEG C.

The present application belongs to the field of ceramic technology, and in particular relates to a microwave dielectric ceramic material, a preparation method thereof, and an application thereof. The microwave dielectric ceramic material comprises a ceramic solid solution having a chemical formula of xAMoO4‑yLi2MoO4; wherein the A position comprises at least five transition metal elements, the total molar content of the transition metal elements is 100%, 0<x<1, 0<y<1, and x+y=1. Through the combined action of the components in the ceramic solid solution, the sintering temperature of the microwave dielectric ceramic material is reduced to below 700°C, and the material has microwave dielectric properties such as a higher relative dielectric constant and quality factor, and a lower temperature drift coefficient, thereby improving the transmission efficiency of microwave communications, reducing signal loss, and reducing interference. The material can more effectively store and release energy, and the ceramic material is less affected by temperature changes, thereby improving the stability of microwave dielectric properties and service life.

The application discloses a kind of multi-element mineral microwave dielectric ceramic materials and preparation method thereof, multi-element mineral microwave dielectric ceramic materials, by the following weight fraction raw materials sintering is obtained: 192~224 parts black talc, 160~192 parts wollastonite, 8~12 parts MgO, 4~8 parts SnO2, 2~4 parts kaolin tailings.Preparation method includes the following steps: broken fine sieving, obtain black talc powder, wollastonite powder and kaolin tailings powder;Take black talc powder and MgO powder, ball milling is mixed;Add wollastonite powder, continue ball milling;Drying, calcination, heat preservation, with furnace cooling;The obtained powder and proportionally weighed SnO2 powder, kaolin tailings powder, ball milling is uniformly mixed, drying;After powder preparation blank, sintering.The application improves the microwave dielectric properties of ceramic material, selects kaolin tailings powder as sintering additive, reduces sintering temperature under the premise of not reducing ceramic dielectric properties.

A CaO-B2O3-SiO2-CaF2 glass-ceramic and its preparation method and application belong to the technical field of chip-type and integrated passive components. The present invention provides a CaO-B2O3-SiO2-CaF2 glass-ceramic comprising the following components in molar percentage: CaO 40-50mol%, B2O3 3-18mol%, SiO2 35-45mol%, and CaF2 5-18mol%. The particle size D of the CaO-B2O3-SiO2-CaF2 glass-ceramic is 200-3000 nm. 50 The nanostructured CaO-B2O3-SiO2-CaF2 glass-ceramics has a low softening point, a wide sintering window, a high degree of densification, and excellent microwave dielectric properties, and is even better compatible with co-firing electrodes.

The application relates to the field of electronic information functional ceramics and electronic devices, and discloses a kind of ultra-low dielectric constant microwave dielectric ceramic and preparation method thereof, the composition expression of the ultra-low dielectric constant microwave dielectric ceramic is: xMg2SiO4-(1-x)LiAl 0.925 B 0.075 O2+ywt.%MO, MO is sintering aid, wherein: 0.2<=x<=0.4, 0.5<=y<=1, the sintering temperature of the ultra-low dielectric constant microwave dielectric ceramic is 1000~1100 DEG C, the dielectric constant of the microwave dielectric ceramic prepared by the application can reach 4.9~5.8, Qxf value can reach 51539~60754 GHz, frequency temperature coefficient Tf can reach-16.2~-11.3ppm / DEG C, the ultra-low dielectric constant microwave dielectric ceramic can be prepared at lower sintering temperature, meanwhile Qxf value is high, better microwave dielectric performance can be obtained, and the resonant frequency temperature coefficient is low, and temperature stability is good.

The present invention discloses a low-loss temperature-stable celsian-based microwave dielectric ceramic material and a preparation method thereof. The low-loss temperature-stable celsian-based microwave dielectric ceramic material is sintered from raw materials in the following weight parts: 265-272 parts of graphite tailings, 160-165 parts of BaCO3, 104-112 parts of Al2O3, 5-8 parts of TiO2, and 1-2 parts of CuO. The preparation method includes the following steps: crushing, grinding, and sieving the graphite tailings, calcining and cooling to obtain graphite tailings powder; weighing the raw materials, ball-milling and mixing; drying, calcining, and cooling with the furnace; performing secondary ball-milling and drying; preparing a blank and sintering. The present invention realizes the in-situ synthesis of a CaTiO3 performance enhancement phase, improves the temperature drift characteristics of the celsian-based ceramic material, the temperature coefficient of resonant frequency can be controlled within ±2 ppm / °C, comprehensively improves the microwave dielectric properties of the ceramic material, and enables it to meet the application requirements of millimeter-wave communication devices.

The application discloses a preparation method of low-dielectric-loss high Q × f value lithium titanate-based microwave dielectric ceramic material and a product thereof.The application takes Li2CO3, TiO2, Sc2O3 and Nb2O5 as raw materials, substitutes Ti in Li2TiO3 with (Sc 1 / 2Nb 1 / 2 ) 4+ , forms a lithium titanate-based microwave dielectric ceramic material with a chemical formula of Li2Ti 4+ (Sc 1‑x Nb 1 / 2 ) 1 / 2 x O3, effectively adjusts the phase structure of the microwave dielectric ceramic, optimizes the temperature frequency characteristics and dielectric loss, and obtains excellent comprehensive microwave dielectric performance with moderate dielectric constant, super high Q × f value and near-zero resonance frequency temperature coefficient, so that the lithium titanate-based microwave dielectric ceramic material has great application potential in the fields of next-generation mobile communication and satellite communication.

The invention discloses a low-temperature sintering temperature-stable oxyfluoride nanocrystalline ceramic and a preparation method thereof, the chemical formula of the nanocrystalline ceramic is Li3Mg2SbO5. 8F0.4, the crystal structure of the nanocrystalline ceramic is composed of an orthorhombic-phase primary crystal phase and a cubic-phase secondary crystal phase, and the average grain size is 220-240 nm. A proper amount of MgF2 is introduced into Li3Mg2SbO6 to serve as a magnesium source, so that the Li3Mg2SbO6-based ceramic crystal structure and the grain size are changed, and meanwhile, the Li3Mg2SbO6-based ceramic has low-temperature sintering (1t, 900 DEG C) and good microwave dielectric properties: tau f is-13.1 to-9.5 ppm / DEG C, Q * f is 33300 to 56600 GHz, and epsilon r is 9.8 to 10.4. The ceramic material is simple in preparation process, rich in raw materials, low in cost and beneficial to industrial production, and can be widely applied to manufacturing of low-temperature co-fired ceramic systems, dielectric resonators, dielectric antennas and other electronic components.

This invention relates to the field of dielectric ceramics technology, specifically to a low-dielectric-high-entropy microwave dielectric ceramic with a garnet structure and its preparation method. The chemical composition formula of the low-dielectric-high-entropy microwave dielectric ceramic with a garnet structure is Ca. 3 (Co 0.2 Cu 0.2 Mg 0.2 Zn 0.2 Ni 0.2 ) 2 SiV 2 O 12 By introducing the high-entropy effect into the garnet structure and optimizing the sintering temperature, a Ca with a garnet structure was successfully synthesized. 3 (Co 0.2 Cu 0.2 Mg 0.2 Zn 0.2 Ni 0.2 ) 2 SiV 2 O 12 Pure-phase low-dielectric-high-entropy microwave dielectric ceramics. They exhibit a dielectric constant of 6.5–10.4, a quality factor of 12490–62440 GHz, and a temperature coefficient of resonant frequency of -9.2–-7.4 ppm / ℃. These ceramics possess excellent microwave dielectric properties and have significant practical application value.

The present invention discloses a low-temperature sintered modified molybdenum-based microwave dielectric ceramic and a preparation method thereof, belonging to the production technology field of microwave dielectric ceramics. The raw materials of the modified molybdenum-based microwave dielectric ceramic are Al2O3, MoO3, MnCO3 and TiO2, and its chemical formula is Al2Mo 3‑x (MnTi) x O 12 , wherein x = 0.01 to 0.02; a method for preparing a modified molybdenum-based microwave dielectric ceramic, comprising the following steps: batching; ball milling, drying, screening, pre-sintering; re-ball milling, drying, granulation; pressing, debinding, and heat preservation to obtain a low-temperature sintered modified molybdenum-based microwave dielectric ceramic, the chemical formula of which is Al2Mo 3‑x (MnTi) x O 12 , wherein x = 0.01 to 0.02. The present invention utilizes (MnTi) 6+ The composite ions partially replace the lattice position of Mo, and with the help of the low melting point of MnCO3, the Al2Mo3O 12 The crystal structure was improved and its optimal sintering temperature was lowered. Finally, the system achieved excellent microwave dielectric properties at a lower sintering temperature (725℃).

The invention discloses a microwave-energy storage integrated dielectric ceramic material with a multiphase structure as well as a preparation method and application thereof, and the method comprises the following steps: 1, weighing Ca2CO3, MgO and TiO2, mixing, and sequentially carrying out ball milling, drying and calcining to obtain Ca0. 8Mg0. 2TiO3 powder; 2, weighing Sm2O3 and Al2O3, mixing the Sm2O3 and the Al2O3, and sequentially carrying out ball milling, drying and calcining on the Sm2O3 and the Al2O3 to obtain SmAlO3 powder; 3, weighing Ca0. 8Mg0. 2TiO3 powder and SmAlO3 powder according to a stoichiometric formula (1-x) Ca0. 8Mg0. 2TiO3-xSmAlO3, x is greater than or equal to 0.28 and less than or equal to 0.40, mixing the Ca0. 8Mg0. 2TiO3 powder and the SmAlO3 powder, and sequentially carrying out ball milling, drying, grinding and sieving to obtain a sieved material; 4, the sieved material is subjected to compression molding and calcination, the microwave-energy storage integrated dielectric ceramic material with the multiphase structure is obtained, the dielectric constant epsilon r of the microwave-energy storage integrated dielectric ceramic material is 35-85, the breakdown electric field intensity Eb is 300-700 kV / cm, the energy storage density U is 1.5-3.5 J / cm < 3 >, the Qf is 23000-34000 GHz, in the temperature range of-150-350 DEG C, the variation delta epsilon r of the dielectric constant is smaller than or equal to + / -5%, the loss tangent tan delta is smaller than or equal to 5 * 10 <-3 >, and the microwave-energy storage integrated dielectric ceramic material with the multiphase structure is obtained. The microwave dielectric property and the energy storage property are excellent.

The invention discloses a preparation method of Li3Mg2SbO6 ceramic with improved sintering characteristic and microwave dielectric property, which comprises the following steps: weighing Li2CO3, MgO and Sb2O5 according to the stoichiometric ratio of the general chemical formula Li3Mg2SbO6, mixing, ball-milling until the materials are uniformly mixed, drying and sieving to obtain a primary ball-milled material; the primary ball-milled material is placed in a box-type furnace for high-temperature presintering, the presintering temperature is 800-1000 DEG C, the presintering time is 2-6 hours, and secondary ball-milled material is obtained after ball milling, drying and sieving are conducted again; performing cold isostatic pressing on the secondary ball-milled material to obtain a ceramic green body; the ceramic green body is placed in a box-type furnace for high-temperature sintering, the sintering temperature ranges from 1350 DEG C to 1500 DEG C, the sintering time ranges from 2 hours to 6 hours, and the Li3Mg2SbO6 microwave dielectric ceramic is obtained. The preparation process is simple, the sintering characteristic of the ceramic is improved, the obtained microwave dielectric ceramic is a pure phase, the density is relatively high, and the commercialization of Li3Mg2SbO6 ceramic is favorably realized.

The invention discloses an Mg3TiO5 microwave dielectric material and a preparation method thereof, and belongs to the field of microwave dielectric materials, the chemical formula of the microwave dielectric material is Mg3TiO5, the Q * f of the microwave dielectric material is 198000GHz, and the fluctuation of the microwave dielectric property within the range of-50 DEG C to 200 DEG C is less than or equal to 5%; the preparation method comprises the following steps: (1) proportioning MgO or basic magnesium carbonate with the purity of more than 99% and the particle size of 400-600nm and TiO2 according to product element composition to obtain initial powder; (2) carrying out ball milling, drying, sieving and presintering on the initial powder obtained in the step (1), and then carrying out secondary ball milling, drying and sieving; and (3) adding a polyvinyl alcohol solution into the powder obtained in the step (2) for granulation, then carrying out compression molding, and sintering the obtained green body in the air atmosphere of 1320-1440 DEG C to obtain the Mg3TiO5 microwave dielectric material.

The invention discloses a high-entropy perovskite microwave dielectric ceramic with medium and high dielectric constants and a preparation method and application thereof, the stoichiometric formula of the high-entropy perovskite microwave dielectric ceramic is (Ca < 0.2 > Li < 0.2 > Sm < 0.2 > Mg < 0.2 > Me < 0.2 >) TiO3, Me is Zn, Ba or Sr; the microwave dielectric constant of the microwave dielectric ceramic is 50-115, the quality factor is 2000-11000 GHz, and the temperature coefficient of resonance frequency is 40-140 ppm / DEG C. The high-entropy perovskite microwave dielectric ceramic with excellent microwave dielectric properties is prepared through a simple, green and environment-friendly process, and the sintering temperature is effectively reduced under the condition that a sintering aid is not added; the method has important significance in promoting the application of the perovskite structure microwave dielectric ceramic in microwave antennas and 6G base stations in the field of mobile communication.

The application discloses a non-metallic mineral matter cordierite type microwave dielectric ceramic material, which is sintered from the following raw materials: black talc powder, coal-based kaolin ore powder, bauxite powder and Sm-Mn composite sintering additives, wherein the Sm-Mn composite sintering additives are prepared by pre-sintering Sm2O3 and Mn(NO3)2.4H2O, and the mass percentage of each raw material in the total amount of black talc powder, coal-based kaolin ore powder, bauxite powder, Sm2O3 and Mn(NO3)2.4H2O is as follows: the black talc powder accounts for 46-49%, the coal-based kaolin ore powder accounts for 15-19%, the bauxite powder accounts for 27-31%, the Sm2O3 accounts for 0.5-1.5%, and the Mn(NO3)2.4H2O accounts for 4.5-5.5%, and the main phase of the non-metallic mineral matter cordierite type microwave dielectric ceramic material is cordierite Mg2Al4Si5O 18 12, the secondary phase is SmMn2O5 and MnO2. The application further discloses a preparation method, wherein the Sm-Mn composite sintering additives are sintered first, and then mixed with the mineral raw materials in proportion to prepare by a solid phase sintering method. The non-metallic mineral matter microwave dielectric ceramic material prepared by the application solves the problem of microwave dielectric performance deterioration caused by impurities in the mineral raw materials.

The invention relates to the field of electronic information functional ceramics and electronic devices, and discloses a low-temperature sintered microwave dielectric material and a preparation method thereof.The composition expression of the microwave dielectric material is xLi [Mg0. 98 (Li2 / 3Sn1 / 3) 0.02] 3TiO6-(1-x) Ca0. 8Sm0. 4 / 3TiO3 + ywt.% MO, MO is a sintering aid, x is larger than or equal to 0.1 and smaller than or equal to 0.5, y is larger than or equal to 0.4 and smaller than or equal to 1, y is larger than or equal to 0.4 and smaller than or equal to 1, and y is larger than or equal to 1 and smaller than or equal to 1. A microwave dielectric ceramic material prepared from the prepared microwave dielectric material at the sintering temperature of 1100-1250 DEG C has excellent microwave dielectric properties, the dielectric constant can reach 40-55, the Q * f value can reach 45000-60000 GHz, and the frequency temperature coefficient tau f can reach 0.8-4.9 ppm / DEG C.

The invention belongs to the technical field of microwave dielectric ceramic materials, and particularly relates to a magnesium and tungsten ion substituted ZnTiNb2O8 microwave dielectric ceramic material and a preparation method thereof, the material uses (Mg0. 5W0. 5) 4 + ions to replace Ti sites in ZnTiNb2O8 crystals, the chemical formula is Zn (Ti1-x (Mg0. 5W0. 5) x) Nb2O8, 0.03 < = x < = 0.15, the dielectric constant of the microwave dielectric ceramic material is 28-34, the quality factor is 29000-39300 GHz, and the temperature coefficient of resonance frequency is-73.5--47.1 ppm / DEG C. The microwave dielectric property of the original ceramic can be improved by replacing Ti site with (Mg0. 5W0. 5) 4 < + > ions, and the microwave dielectric ceramic is suitable for being used as a substrate material for microwave resonators, antennas and related electronic circuits. The temperature coefficient of resonance frequency and the quality factor of the ceramic are improved, the improvement of the temperature coefficient of resonance frequency can ensure the environmental stability of a device, and the high quality factor ensures the low loss and the low heat effect of the device in work.

The invention discloses a single-phase La-Bi-B-based microwave dielectric ceramic material and a preparation method thereof, and belongs to the technical field of functional ceramic materials, the molecular formula is La1-xBixBO3, and x is greater than or equal to 0 and less than or equal to 0.12; the preparation method comprises the following steps: taking La2O3, B2O3 and Bi2O3 as raw materials, carrying out ball milling in water, and drying to obtain raw material powder; heating the raw material powder to 930-960 DEG C for calcining, then ball-milling and uniformly mixing in water, and drying to obtain a pre-sintered material; mixing and granulating the pre-sintered material and an adhesive to obtain green body particles, and carrying out compression molding on the green body particles to obtain a green body; and calcining the green body under the condition of 1050-1100 DEG C, thereby obtaining the product. Pure phase replacement of La < 3 + > by Bi < 3 + > is realized in a LaBO3 ceramic system, excellent microwave dielectric properties are maintained at the sintering temperature lower than the melting point of a copper electrode, and the material can be used as a high-quality substrate material of a leakage mode dielectric resonant cavity antenna in a microwave frequency band.

The present application relates to a kind of low dielectric loss and low temperature coefficient microwave dielectric ceramic and its preparation method, the preparation method includes the following steps: after mixing zinc lanthanum titanate, strontium source and auxiliary raw material, sequentially forming and sintering, the low dielectric loss and low temperature coefficient microwave dielectric ceramic is prepared;The auxiliary raw material includes any one or combination of at least two of calcium carbonate, manganese dioxide or barium carbonate.The present application selects zinc lanthanum titanate and strontium titanate with good microwave dielectric properties as basic raw material to ensure the basic performance of ceramic;Introduce appropriate amount of calcium carbonate, manganese dioxide and barium carbonate, effectively reduce the dielectric loss of ceramic, and improve its temperature characteristics;The present application reduces production cost and technical difficulty by solid phase reaction method, while ensuring the uniformity and stability of ceramic, effectively reduces the dielectric loss of microwave dielectric ceramic, and improves its temperature characteristics, further improves the performance of ceramic.

The application relates to an environment-friendly scheelite high-entropy microwave dielectric ceramic material and a preparation method thereof. 0.5 (LaPrNdX) 0.5 / N MoO4, wherein X is at least two selected from Bi, Ce, Sm, Eu and Y, N is the sum of the element types of La, Pr, Nd and X. The ceramic material simultaneously has at least five elements of La, Pr, Nd and X in one element position, realizes high-entropy component design, can direct design of dielectric properties of the material through component selection, effectively reduces the sintering temperature of the material under the condition that no sintering aid is added, has reasonable dielectric constant, high quality factor and near-zero resonance frequency temperature coefficient, and exhibits excellent microwave dielectric properties.

The invention relates to the technical field of ceramic materials, in particular to microwave dielectric property wide-range adjustment of europium niobate-based microwave dielectric ceramics and a preparation method of the europium niobate-based microwave dielectric ceramics, according to the method, three performance parameters of EuNbO4 are regulated and controlled through the cooperation of A / B site regulation, ratling effect and compact effect, the chemical formula of the europium niobate-based microwave dielectric ceramics is Eu1-xCaxNb1-xMoxO4 (0 < = x < = 0.38), Nb2O5, Eu2O3, CaCO3 and MoO3 are used as raw materials, and the europium niobate-based microwave dielectric ceramics are prepared through a one-step method. The europium niobate-based microwave dielectric ceramic is prepared by the processes of ball milling, sintering and the like, the prepared europium niobate-based microwave dielectric ceramic realizes wide-range adjustment of dielectric constant, quality factor and resonant frequency temperature coefficient, and the europium niobate-based microwave dielectric ceramic has the advantages of improving selectivity of working frequency of a device, simplifying heat dissipation design and the like when being made into a substrate integrated resonant antenna.

The application relates to the field of electronic information functional ceramics and electronic devices, and discloses a low-temperature sintering microwave dielectric material and a preparation method thereof. 0.98 (Li 2 / 3 Sn 1 / 3 ) 0.02 ]3TiO6‑(1‑x)Ca 0.8 Sm 0.4 / 3 TiO3+ywt.%MO, the MO being a sintering aid, wherein 0.1<=x<=0.5 and 0.4<=y<=1; the microwave dielectric material prepared by the application has excellent microwave dielectric properties: the dielectric constant can reach 40-55, the Qxf value can reach 45000-60000 GHz, and the frequency temperature coefficient tauf can reach 0.8-4.9 ppm / degree Celsius.

The invention relates to the technical field of ceramic materials, in particular to low-dielectric molybdenum-based microwave dielectric ceramic with adjustable wide-range microwave dielectric property and a preparation method thereof, the chemical formula of the low-dielectric molybdenum-based microwave dielectric ceramic is Ca1-xEuxMo1-xNbxO4 (x is greater than or equal to 0.1 and less than or equal to 0.6), and the preparation method of the low-dielectric molybdenum-based microwave dielectric ceramic comprises the following steps: taking Nb2O5, Eu2O3, CaCO3 and MoO3 as raw materials, and carrying out primary ball milling, pre-sintering, drying, secondary ball milling, drying, granulating, developing, forming and sintering to prepare the low-dielectric molybdenum-based microwave dielectric ceramic. The molybdenum-based microwave dielectric ceramic material has the advantages that the molybdenum-based microwave dielectric ceramic material is prepared from Ca0. 4Eu0. 6Mo0. 4Nb0. 6O4 and Ca0. 4Eu0. 6Mo0. 4Nb0. 6O4, the regulation range of the molybdenum-based microwave dielectric ceramic material is widened in a process temperature and component doping coordinated regulation mode, the quality factor (Q * f) value of the Ca0. 4Eu0. 6Mo0. 4Nb0. 6O4 prepared at the sintering temperature of 1400 DEG C is 82930 GHz, the dielectric constant (epsilon r) is 15.6, and the temperature coefficient of resonance Meanwhile, a substrate integrated resonant antenna is designed, the gain at the center resonant frequency (3.69 GHz) is 6.1 dBi, and the gain is S11lt; and the radiation efficiency at a-10dB region reaches 90% or more, and the operation requirement of the 5G communication technology is met.

The invention discloses a preparation method of a lithium titanate-based microwave dielectric ceramic material with low dielectric loss and high Q * f value and a product thereof, Li2CO3, TiO2, Sc2O3 and Nb2O5 are used as raw materials, Ti < 4 + > in Li2TiO3 is replaced by (Sc1 / 2Nb1 / 2) < 4 + >, the lithium titanate-based microwave dielectric ceramic material with the chemical formula of Li2Ti1-x (Sc1 / 2Nb1 / 2) xO3 is formed, and the phase structure of the microwave dielectric ceramic is effectively adjusted, so that the temperature frequency characteristic and dielectric loss of the microwave dielectric ceramic are optimized, and the dielectric property of the microwave dielectric ceramic is improved. The microwave dielectric ceramic prepared by the method has the advantages of moderate dielectric constant, ultrahigh Q * f value and excellent comprehensive microwave dielectric property with near-zero resonant frequency temperature coefficient, so that the microwave dielectric ceramic has huge application potential in the fields of next-generation mobile communication, satellite communication and the like.

This invention discloses a modified molybdenum-based microwave dielectric ceramic sintered at ultra-low temperatures and its preparation method, belonging to the field of microwave dielectric ceramic production technology. The raw materials for the modified molybdenum-based microwave dielectric ceramic are Al2O3, MoO3, Li2CO3, and V2O5, and its chemical formula is xAl2Mo3O 12 A method for preparing modified molybdenum-based microwave dielectric ceramics using the formula (-(1-x)LiMoVO6), where x = 0.01–0.02, includes the following steps: batching; ball milling, drying, sieving, and pre-firing; batching again, ball milling, drying, and granulation; pressing, debinding, and heat preservation to obtain ultra-low temperature sintered modified molybdenum-based microwave dielectric ceramics. This invention introduces Al2Mo3O into the raw material powder of the LiMoVO6 system. 12 The raw material powders of the system form a two-phase coexistence system, which significantly reduces the temperature stability of the resonant frequency while improving the temperature stability of Al2Mo3O. 12 The sintering temperature of the base ceramic was adjusted, and the system ultimately achieved excellent microwave dielectric properties at a lower sintering temperature (600℃).

Providing a dielectric ceramic composition, a method for making the dielectric ceramic composition and related devices. The dielectric ceramic composition includes the following elements: Mg, Ca, Si, Ti, and O. When the dielectric ceramic composition is expressed in terms of oxide form, molar amounts satisfy: 50 mol%≤ MgO ≤ 65 mol%, 3 mol%≤ CaO ≤ 6 mol%, 22 mol%≤ SiO 2≤ 35 mol%, 0.5 mol%≤ La 2O 3 ≤ 1.5 mol%, and 4 mol%≤ TiO 2 ≤ 14 mol%, where MgO+ CaO+ SiO 2 +La 2O 3 + TiO 2 = 100 mol%. The dielectric ceramic composition shows a good combination of microwave dielectric properties.

The invention relates to the field of electronic information functional ceramics and electronic devices, and discloses an ultralow-dielectric-constant microwave dielectric ceramic and a preparation method thereof.The composition expression of the ultralow-dielectric-constant microwave dielectric ceramic is xMg2SiO4-(1-x) LiAl0. 025 B0. 075 O2 + ywt.% MO, MO is a sintering aid, 0.2 < = x < = 0.4, 0.5 < = y < = 1, the sintering temperature of the ultralow-dielectric-constant microwave dielectric ceramic is 1000-1100 DEG C, and the sintering time of the ultralow-dielectric-constant microwave dielectric ceramic is 0.5-1 h. The dielectric constant of the prepared microwave dielectric ceramic can reach 4.9-5.8, the Q * f value can reach 51539-60754 GHz, the frequency temperature coefficient tau f can reach-16.2 to-11.3 ppm / DEG C, the microwave dielectric ceramic with the ultralow dielectric constant can be prepared at the low sintering temperature, meanwhile, the Q * f value is high, good microwave dielectric performance can be obtained, the resonant frequency temperature coefficient is low, and the temperature stability is good.

The invention discloses a low-temperature sintered microwave dielectric ceramic and a preparation method thereof, and the preparation method comprises the following steps: pre-sintered ceramic powder is subjected to wet sanding until the particle size D50 is 0.60-0.68 [mu] m to obtain ceramic slurry; under the condition of high-speed stirring, adding an acid solution into the ceramic slurry, and adjusting the pH value of the system to 9-10; sequentially adding an organic additive system containing a binder, a plasticizer, a dispersant, a lubricant, a defoaming agent and a surface modifier into the ceramic slurry; the obtained mixed slurry is sequentially subjected to drying, granulation, sieving, compression molding, glue discharging and sintering, and the microwave dielectric ceramic is obtained. By optimizing the powder pretreatment and organic additive introduction process, the method realizes full densification sintering of the ceramic at a low temperature of 1150-1250 DEG C, and successfully prepares the microwave dielectric ceramic with high density, excellent microwave dielectric properties and good surface quality.

The present invention relates to a low-dielectric-low-loss LTCC material, a preparation method thereof, and a green ceramic tape. The low-dielectric-low-loss LTCC material is prepared by mixing a ceramic filling phase and a glass low-sintering aid, wherein the ceramic filling phase is a lanthanum borosilicate microwave dielectric ceramic LaBSiO5, and the glass low-sintering aid is La2O3-B2O3 glass. The low-dielectric-low-loss LTCC material of the present invention uses a lanthanum borosilicate microwave dielectric ceramic with low dielectric and low loss characteristics and a low sintering temperature (<1200°C) as the ceramic filling phase, and uses La2O3-B2O3 glass as the glass low-sintering aid. This reduces the loss of the ceramic-glass system and the sintering temperature of the low-dielectric-low-loss LTCC material, allowing the LaBSiO5 material to be sintered within a temperature range below 900°C and having excellent microwave dielectric properties. This allows the LTCC substrate material prepared using the LTCC green ceramic tape to have a low dielectric constant and dielectric loss.