CN103496978A

CN103496978A - Low-temperature sinterable microwave dielectric ceramic Ba2BiV3O11 and its preparation method

Info

Publication number: CN103496978A
Application number: CN201310434742.0A
Authority: CN
Inventors: 苏聪学; 邓婧; 方亮
Original assignee: Guilin University of Technology
Current assignee: Yancheng Xiangguo Technology Co ltd
Priority date: 2013-09-23
Filing date: 2013-09-23
Publication date: 2014-01-08
Anticipated expiration: 2033-09-23
Also published as: CN103496978B

Abstract

本发明公开了一种可低温烧结的微波介电陶瓷Ba₂BiV₃O₁₁及其制备方法。可低温烧结的微波介电陶瓷的组成为Ba₂BiV₃O₁₁。（1）将纯度为99.9%以上的BaCO₃、Bi₂O₃和V₂O₅的原始粉末按Ba₂BiV₃O₁₁化学式称量配料。（2）将步骤（1）原料混合湿式球磨12小时，溶剂为蒸馏水，烘干后在700℃大气气氛中预烧6小时。（3）在步骤（2）制得的粉末中添加粘结剂并造粒后，再压制成型，最后在800~830℃大气气氛中烧结4小时；所述的粘结剂采用质量浓度为5%的聚乙烯醇溶液，剂量占粉末总质量的3%。本发明制备的陶瓷在800-830℃烧结良好，其介电常数达到15～16，品质因数Qf值高达84000-94000GHz，谐振频率温度系数小，在工业上有着极大的应用价值。The invention discloses a low-temperature sinterable microwave dielectric ceramic Ba ₂ BiV ₃ O ₁₁ and a preparation method thereof. The composition of the low-temperature sinterable microwave dielectric ceramic is Ba ₂ BiV ₃ O ₁₁ . (1) The raw powders of BaCO ₃ , Bi ₂ O ₃ and V ₂ O ₅ with a purity of more than 99.9% are weighed according to the chemical formula of Ba ₂ BiV ₃ O ₁₁ . (2) The raw materials in step (1) were mixed and wet-type ball milled for 12 hours, the solvent was distilled water, and after drying, pre-calcined in an atmosphere at 700°C for 6 hours. (3) Add a binder to the powder prepared in step (2) and granulate it, then press it into shape, and finally sinter it in the air atmosphere at 800-830°C for 4 hours; the binder is used at a mass concentration of 5 % polyvinyl alcohol solution, the dosage accounts for 3% of the total mass of the powder. The ceramic prepared by the invention is well sintered at 800-830 DEG C, its dielectric constant reaches 15-16, its quality factor Qf value is as high as 84000-94000 GHz, the temperature coefficient of resonance frequency is small, and it has great application value in industry.

Description

Low temperature sintering microwave dielectric ceramic Ba 2biV 3o 11and preparation method thereof

Technical field

The present invention relates to dielectric ceramic material, particularly relate to microwave dielectric ceramic material of the microwave devices such as medium substrate, resonator and wave filter that use in microwave frequency and preparation method thereof.

Background technology

Microwave dielectric ceramic refers to and is applied in microwave frequency band (being mainly UHF, SHF frequency range) circuit as dielectric material and completes the pottery of one or more functions, be widely used as the components and parts such as resonator, wave filter, dielectric substrate and medium guided wave loop in modern communication, it is the key foundation material of modern communication technology, at aspects such as portable mobile phone, automobile telephone, cordless telephone, telestar susceptor and military radars, very important application is arranged, in the miniaturization of modern communication instrument, integrated process, just bringing into play increasing effect.

Be applied to the dielectric ceramic of microwave frequency band, should meet the requirement of following dielectric characteristics: (1) seriation DIELECTRIC CONSTANT ε _rto adapt to the requirement of different frequency and different application occasion; (2) high quality factor q value or dielectric loss tan δ are to reduce noise, general requirement Qf>=3000 GHz; (3) the temperature factor τ of resonant frequency _?the as far as possible little thermostability to guarantee that device has had, general requirement-10/ ℃≤τ _?≤+10 ppm/ ℃.From late 1930s, just someone attempts dielectric substance is applied to microwave technology in the world.

According to relative permittivity ε _rsize from use the different of frequency range, usually the microwave dielectric ceramic be developed He developing can be divided into to 4 classes.

(1) ultralow dielectric microwave dielectric ceramic, main representative is Al ₂o ₃-TiO ₂, Y ₂baCuO ₅, MgAl ₂o ₄and Mg ₂siO ₄deng, its ε _r≤ 20, quality factor q * f>=50000GHz, τ _?≤ 10 ppm/ ° C.Be mainly used in microwave base plate and high-end microwave device.

(2) low ε _rwith the microwave dielectric ceramic of high Q value, be mainly BaO-MgO-Ta ₂o ₅, BaO-ZnO-Ta ₂o ₅or BaO-MgO-Nb ₂o ₅, BaO-ZnO-Nb ₂o ₅system or the composite system MWDC material between them.Its ε _r=25～30, Q=(1～2) * 10 ⁴(under f>=10 GHz), τ _?≈ 0.Be mainly used in the microwave communication equipments such as direct broadcasting satellite of f >=8 GHz as the dielectric resonance device.

(3) medium ε _rwith the microwave dielectric ceramic of Q value, be mainly with BaTi ₄o ₉, Ba ₂ti ₉o ₂₀(Zr, Sn) TiO ₄deng the MWDC material that is base, its ε _r=35 ~ 40, Q=(6～9) * 10 ³(f=3～-4GHz under), τ _?≤ 5 ppm/ ° C.Be mainly used in the interior microwave military radar of 4～8 GHz range of frequency and communication system as the dielectric resonance device.

(4) high ε _rand the lower microwave dielectric ceramic of Q value is mainly used in civilian mobile communcations system in 0.8～4GHz range of frequency, this is also the emphasis of microwave dielectric ceramic research.Since the eighties, the people such as Kolar, Kato find and have studied perovskite-like tungsten bronze type BaO-Ln in succession ₂o ₃-TiO ₂series (Ln=La, Sm, Nd or Pr etc. are called for short BLT system), complex perovskite structure CaO-Li ₂o-Ln ₂o ₃-TiO ₂series, lead base series material, Ca _1-xln _2x/3tiO ₃be contour ε _rmicrowave dielectric ceramic, the wherein BaO-Nd of BLT system ₂o ₃-TiO ₂material dielectric constant reaches 90, lead base series (Pb, Ca) ZrO ₃specific inductivity reaches 105.

The sintering temperature of above these material systems is generally higher than 1300 ° of C, can not be directly and the low melting point metals such as Ag and Cu burn altogether the formation laminated ceramic capacitor.In recent years, along with LTCC Technology (Low Temperature Co-fired Ceramics, the requirement of development LTCC) and the development of microwave multilayer device, researchist both domestic and external has carried out exploring widely and studying to some low fever's system materials, mainly to adopt devitrified glass or glass-ceramic composite system, because low melting glass has relatively high dielectric loss mutually, the existence of glassy phase has improved the dielectric loss of material greatly.Therefore development is the emphasis of current research without the low temperature sintering microwave dielectric ceramic of glassy phase.

Summary of the invention

The purpose of this invention is to provide a kind of have low-loss and good thermostability, microwave dielectric ceramic that sintering temperature is low simultaneously and preparation method thereof.

The chemical constitution of the low temperature sintering microwave dielectric ceramic the present invention relates to is: Ba ₂biV ₃o ₁₁.

Preparation method's concrete steps of described low temperature sintering microwave dielectric ceramic are:

(1) by purity, be the BaCO more than 99.9% ₃, Bi ₂o ₃and V ₂o ₅starting powder press Ba ₂biV ₃o ₁₁the chemical formula weigh batching.

(2) by step (1) raw material mixing wet ball-milling 12 hours, solvent was distilled water, pre-burning 6 hours in 700 ℃ of air atmosphere after oven dry.

(3) after adding binding agent granulation in the powder made in step (2), then compression moulding, last sintering 4 hours in 800 ~ 830 ℃ of air atmosphere; Described binding agent adopts the polyvinyl alcohol solution that mass concentration is 5%, and dosage accounts for 3% of powder total mass.

Pottery prepared by the present invention is good at 800-830 ℃ of sintering, and its specific inductivity reaches 15～16, and quality factor q f value is up to 84000-94000GHz, and temperature coefficient of resonance frequency is little, industrial great using value is arranged.

Embodiment

Embodiment:

Table 1 shows 4 specific embodiments and the microwave dielectric property thereof that forms different sintering temperatures of the present invention.Its preparation method as mentioned above, carries out the evaluation of microwave dielectric property by the cylindrical dielectric resonator method.

The present invention never is limited to above embodiment.The bound of sintering temperature, interval value can realize the present invention, at this, do not enumerate embodiment.

This pottery can be widely used in the manufacture of the microwave devices such as various medium substrates, resonator and wave filter, can meet the Technology Need of the systems such as mobile communication, satellite communications.

Table 1:

Figure 2013104347420100002DEST_PATH_IMAGE002

Claims

1. The application of a vanadate as a low-temperature sinterable microwave dielectric ceramic, characterized in that the chemical composition formula of the vanadate is: Ba ₂ BiV ₃ O ₁₁ ;

The concrete steps of the preparation method of described vanadate are:

(1) Weigh the raw powders of BaCO ₃ , Bi ₂ O ₃ and V ₂ O ₅ with a purity of more than 99.9% according to the chemical formula of Ba ₂ BiV ₃ O ₁₁ ;

(2) Mix the raw materials of step (1) with wet ball milling for 12 hours, the solvent is distilled water, and after drying, pre-fire in the atmosphere at 700°C for 6 hours;

(3) Add a binder to the powder prepared in step (2) and granulate it, then press it into shape, and finally sinter it in the air atmosphere at 800-830°C for 4 hours; the binder is used at a mass concentration of 5 % polyvinyl alcohol solution, the dosage accounts for 3% of the total mass of the powder.