Temperature-stable high-dielectric-constant dielectric ceramic Ba6Ti3Zr5Nb8O42 and preparation method thereof

Abstract

The invention discloses a temperature-stable high-dielectric-constant dielectric ceramic Ba6Ti3Zr5Nb8O42 and a preparation method thereof. The preparation method comprises the following steps: (1) weighing and proportioning BaCO3, TiO2, ZrO2 and Nb2O5 original powders with the purity of higher than 99.9 wt% according to the composition of the Ba6Ti3Zr5Nb8O42; (2) carrying out wet ball milling mixing on the raw materials in the step (1) for 12 hours by using distilled water as a ball milling medium, drying, and presintering in a 1300-DEG C atmospheric atmosphere for 6 hours; and (3) adding an adhesive into the powder prepared in the step (2), granulating, compacting, and finally, sintering in a 1350-1400-DEG C atmospheric atmosphere for 4 hours, wherein the adhesive adopts a 5 wt% polyvinyl alcohol solution, and the addition amount of the polyvinyl alcohol is 3% of the total mass of the powder. The ceramic has favorable sintering property, the dielectric constant reaches 81.3-83.9, the quality factor Qf value is up to 34000-42000 GHz, the temperature coefficient of resonance frequency is small, and the ceramic has great application value in industry.

Description

technical field [0001] The invention relates to a dielectric ceramic material, in particular to a dielectric ceramic material for manufacturing microwave components such as ceramic substrates, resonators and filters used in microwave frequencies and a preparation method thereof. Background technique [0002] Microwave dielectric ceramics refer to ceramics that are used as dielectric materials in circuits in the microwave frequency band (mainly UHF and SHF bands) and perform one or more functions. They are widely used as resonators, filters, and dielectric substrates in modern communications. Components such as chips and dielectric waveguide circuits are the key basic materials of modern communication technology. They have been used in portable mobile phones, car phones, cordless phones, TV satellite receivers and military radars. They are used in modern communication tools. It is playing an increasingly important role in the process of miniaturization and integration. [00...

AI Technical Summary

Problems solved by technology

[0008] Due to the three performance indicators of microwave dielectric ceramics (ε r with Q f and τ ? ) is a mutual restrictive relationship (see literature: The restrictive relationship between the dielectric properties of microwave dielectric ceramic materials, Zhu Jianhua, Liang Fei, Wang Xiaohong, Lu Wenzhong, Electronic Components and Materials, Issue 3, March 2005), satisfying three There are very few high-dielectric constant microwave dielectric ceramics with individual performance requirements, mainly because their resonant frequency temperature coefficient is usually too large or the quality factor is too low to meet the practical application requirements.

At present, most of the research on microwave dielectric ceramics is a summary of experience obtained through a large number of experiments, but there is no complete theory to explain the relationship between microstructure and dielectric properties. Predict the microwave dielectric properties such as its resonant frequency temperature coefficient and quality factor, explore and develop near-zero resonant frequency temperature coefficient (-10 ppm / ℃≤τ ? ≤+10 ppm / ℃) and a series of high-permittivity microwave dielectric ceramics with higher quality factors are difficult problems that those skilled in the art have been eager to solve but have always been difficult to achieve, which largely limits the development of microwave dielectric ceramics. and device development

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