Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Low-temperature sintering near-zero resonance frequency temperature coefficient cadmium tungstate-based composite ceramics and preparation method thereof

A technology of composite ceramics and resonant frequency, applied in the field of near-zero resonant frequency temperature coefficient cadmium tungstate-based composite ceramics and its preparation, can solve the problem of high sintering temperature and achieve excellent microwave dielectric properties

Inactive Publication Date: 2015-11-18
SHAANXI NORMAL UNIV
View PDF1 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, it has a higher sintering temperature (1150°C) and a larger negative τ f value and other shortcomings, thus limiting its further application

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Low-temperature sintering near-zero resonance frequency temperature coefficient cadmium tungstate-based composite ceramics and preparation method thereof
  • Low-temperature sintering near-zero resonance frequency temperature coefficient cadmium tungstate-based composite ceramics and preparation method thereof
  • Low-temperature sintering near-zero resonance frequency temperature coefficient cadmium tungstate-based composite ceramics and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] To prepare cadmium tungstate based composite ceramics 0.80CdWO 4 -0.20TiO 2 For example, the materials used and the preparation method are as follows:

[0021] 1. Preparation of CdWO 4 Burnt powder

[0022] According to CdWO 4 The stoichiometric ratio of raw materials CdO (purity>99.0%) 10.6931g, WO 3 (Purity>99.0%) 19.3069g is put into a tungsten carbide ball mill jar with an inner diameter of 80mm, and then add 2 tungsten carbide balls with a diameter of 20mm, 8 tungsten carbide balls with a diameter of 10mm and several tungsten carbide balls with a diameter of 5mm, the total mass of tungsten carbide balls 450g, using Pulverisette4 planetary high-energy ball mill for ball milling, the revolution speed is 300 revolutions per minute, the rotation speed is 450 revolutions per minute, and the rotation direction is opposite to the revolution direction. Stop cooling for 30 minutes after every 1 hour of ball milling, the total ball milling time is 30 hours, and the mixt...

Embodiment 2

[0028] In step 2 of Example 1, after the green body is kept at 500°C for 2 hours, the temperature is raised to 925°C for 3 hours, and then the temperature is lowered with the furnace. The other steps are the same as in Example 1 to make cadmium tungstate-based composite ceramics .

Embodiment 3

[0030] To prepare cadmium tungstate based composite ceramics 0.79CdWO 4 -0.21TiO 2 For example, the materials used and the preparation method are as follows:

[0031] Prepare CdWO according to step 1 of Example 1 4 Burnt powder. In step 2 of preparing cadmium tungstate-based composite ceramics, according to 0.79CdWO 4 -0.21TiO 2 The stoichiometric ratio of the raw material CdWO was weighed 4 Calcined powder 23.0000g and rutile phase TiO with a particle size of 30-60nm 2 1. 3560g, put into a polytetrafluoroethylene ball mill jar, use absolute ethanol as the ball milling medium, mill with agate balls for 5 hours, then dry at 70-80°C for 10 hours, add 5%-10% of the mass fraction of raw materials It is a 5% polyvinyl alcohol aqueous solution, granulated, passed through a 120 mesh sieve, left to stand at room temperature for 24 hours, and made into a cylindrical raw material with a diameter of 11.5 mm and a thickness of 5 to 6 mm with a powder tablet press under a pressure of...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
particle sizeaaaaaaaaaa
sizeaaaaaaaaaa
particle sizeaaaaaaaaaa
Login to View More

Abstract

The invention discloses low-temperature sintered cadmium tungstate-based composite ceramic with near-zero temperature coefficient of resonance frequency and a preparation method thereof. The composite ceramic is represented by (1-x)CdWO4-xTiO2, wherein in the formula, x is 0.20-0.22. The preparation method comprises the steps of preparing CdWO4 presintering powder with uniform particle size and average size of 200-250nm by using a high-energy ball milling method; and then compounding the CdWO4 presintering powder with 30-60nm of TiO2 to obtain the cadmium tungstate-based composite ceramic. By introducing nanometer TiO2 with a positive temperature coefficient into cadmium tungstate ceramic, the sintering temperature of the cadmium tungstate ceramic is reduced from 1025 DEG to 900-925 DEG C, the temperature coefficient of resonance frequency is near zero, and the Q*f value is high; the ceramic coexists with Ag, and can be widely applied to manufacturing of low-temperature cofiring ceramic systems, GPS antennas, filters for wireless local area networks, microwave devices such as microwave substrates, etc.

Description

technical field [0001] The invention belongs to the technical field of electronic ceramics and its manufacture, and specifically relates to a microwave dielectric material, in particular to a near-zero resonance frequency temperature coefficient cadmium tungstate-based composite ceramic and a preparation method thereof. Background technique [0002] Microwave dielectric ceramics refer to ceramic materials used in microwave frequency band (300MHz ~ 300GHz) circuits as dielectric materials to complete one or more functions, and are the key to the preparation of components such as resonators, filters, and microwave integrated circuit substrates. It is widely used in modern communication technology fields such as mobile communication, wireless local area network and military communication. With the development of modern communication equipment in the direction of miniaturization, integration, high reliability and low cost, multi-layer structure design based on low temperature co...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C04B35/495C04B35/622
CPCC04B35/495C04B2235/3232C04B2235/3258C04B2235/3284C04B2235/5454
Inventor 刘鹏郭保春张怀武
Owner SHAANXI NORMAL UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com