CN105801112A - Nd and Al co-doped substituted Ba0.4Sr0.6TiO3 giant dielectric ceramic and preparation method thereof - Google Patents

Abstract

The invention discloses an Nd and Al co-doped substituted Ba0.4Sr0.6TiO3 giant dielectric ceramic and a preparation method thereof. Al is substituted for Ti at a low valence, Nd is substituted for Ba at a high valence, and the Nd and Al co-doped substituted Ba0.4Sr0.6TiO3 giant dielectric ceramic is expressed as the formula xNd2O3-yAl2O3-Ba0.4Sr0.6TiO3, wherein in the formula, 0.005<=x<=0.01, and 0.005<=y<=0.01. The Nd and Al co-doped substituted Ba0.4Sr0.6TiO3 giant dielectric ceramic is obtained by performing heat preservation sintering on a ceramic body at 1360-1400 DEG C, wherein the ceramic body is prepared by mixing Ba0.4Sr0.6TiO3, Nd2O3 and Al2O3 at the stoichiometric ratio of 1:x:y. The Nd and Al co-doped substituted Ba0.4Sr0.6TiO3 giant dielectric ceramic is high in dielectric constant, good in dielectric constant temperature stability and capable of keeping a giant dielectric constant within a very wide frequency range; the preparation method is simple, good in repeatability and high in yield, no additional atmosphere is needed for assisting in sintering, and production is easy.

Description

Nd, Al codope replaces Ba0.4Sr0.6TiO3Giant dielectric pottery and preparation method thereof

Technical field

The invention belongs to dielectric ceramic material technical field, be specifically related to a kind of Nd, Al codope and replace Ba_0.4Sr_0.6TiO₃Huge Jie Electroceramics and preparation method thereof.

Background technology

Along with electronic devices and components miniaturization, demands integrated, intelligentized such as the fast development of microelectronic industry, ceramic capacitors Improving constantly.Improve the memory density of dynamic RAM (DRAM), it is ensured that signal can be stored in less On area, it is necessary to use the dielectric constant dielectric substance relatively low compared with lossy to ensure reducing the size of dielectric substance simultaneously, Not affecting capacitance and leakage current, therefore the research of the dielectric substance of high-k, low-dielectric loss is increasingly by people Concern.How to prepare that dielectric constant is high, dielectric loss is low and dielectric properties temperature and the good electrolyte of frequency stability Material also becomes one of the important topic in new material research field.It is normal that CCTO material was just found to have giant dielectric before very early Number, but owing to too high dielectric loss is difficult to apply in the electronic devices and components that capacitor, memorizer etc. need high-k. Have a lot with SrTiO afterwards₃It is that main matrix studies huge dielectric constant, the dielectric substance of low-dielectric loss.xNd₂O₃-SrTiO₃ Pottery there will be giant dielectric phenomenon, but dielectric constant is the most on the low side in 20～340 DEG C of temperature ranges, in 20～160 DEG C of temperature ranges Dielectric constant is less than 500, and temperature end dielectric constant is less than 16000, and the narrow range of dielectric constant temperature stability, In 0.04～300kHz frequency range, the frequency stability of dielectric constant is poor, and in this frequency range, dielectric loss is generally higher than 0.8, Even there is the loss of up to 4.0.Consider stoichiometrically doping preparation Nd_xSr_1-xTi_1-x/4O₃, room temperature dielectric constant obtains bigger Raising, in terms of temperature, frequency stability, there is no improvement clearly.The rear-earth-doped SrTiO of nitrogen assisted sintering₃, increase Adding the Lacking oxygen in system, it is possible to have the highest dielectric constant in room temperature, dielectric loss also can reach the lowest numerical value, but Dielectric properties are affected very big by atmosphere, tube furnace, and the best meeting of tube furnace sealing makes dielectric loss under room temperature the highest.Also Have and pass through Nd₂O₃Doping Ba_0.3Sr_0.7TiO₃Obtain giant dielectric pottery, dielectric constant～when 10000, dielectric loss～0.1,1kHz Under frequency, temperature range is 25～500 DEG C, and dielectric constant is respectively less than 8000.

Ba_0.4Sr_0.6TiO₃Pottery belongs to BST based material, is in paraelectric state (Tc ≈-70 DEG C), has high-k under room temperature The advantages such as (ε r ≈ 1000), low-dielectric loss (tg δ ≈ 0.005), frequency and temperature stability are good, are widely used in electron trade In the components and parts such as capacitor, phase shifter.Rear-earth-doped is to improve a kind of effective means of media ceramic dielectric constant, but again can Improve dielectric loss in various degree, in order to reach relatively low dielectric loss while keeping very high-k, need to mix difference Element replace the diverse location in perovskite structure, donor doping acts on jointly with acceptor doping, the polarizability of enhancing system Suppress electronic conductance by charge compensation, reduce dielectric loss.

Summary of the invention

Present invention aim at providing a kind of huge dielectric constant, relatively low-dielectric loss and good temperature stability and frequency stable Property Nd, Al codope replace Ba_0.4Sr_0.6TiO₃Giant dielectric pottery and preparation method thereof.

For solving above-mentioned technical problem the technical solution adopted in the present invention it is:

A kind of Nd, Al codope replaces Ba_0.4Sr_0.6TiO₃Giant dielectric pottery, is replaced Ti at a low price, Nd high price replaces by Al Ba, uses xNd₂O₃-yAl₂O₃-Ba_0.4Sr_0.6TiO₃Represent, 0.005≤x≤0.01 in formula, 0.005≤y≤0.01.

By such scheme, described Nd, Al codope replaces Ba_0.4Sr_0.6TiO₃Giant dielectric ceramic material is by Ba_0.4Sr_0.6TiO₃、 Nd₂O₃、Al₂O₃By xNd₂O₃-yAl₂O₃-Ba_0.4Sr_0.6TiO₃The ceramic body that is mixed of stoichiometric proportion 1:x:y in 1360～1400 DEG C of heat preservation sinterings and obtain.

Above-mentioned Nd, Al codope replaces Ba_0.4Sr_0.6TiO₃The preparation method of giant dielectric pottery, comprises the following steps:

1) by Ba_0.4Sr_0.6TiO₃、Nd₂O₃And Al₂O₃Mixing, adds ball milling after dispersant, obtains composite granule after drying；

2) composite granule is added binding agent pelletize and sieve, molding, then binder removal obtains ceramic body；

3) by ceramic body heat preservation sintering 1～4h at 1360～1400 DEG C, with stove natural cooling.

Being dehydrated alcohol by dispersant in such scheme, step 1, ball-milling medium is zirconium ball；Wherein compound: dehydrated alcohol: Zirconium ball is in mass ratio for 1:(4～5): (10～14) carry out ball milling.

Sticking with glue agent by pelletize in such scheme, step 2 is poly-vinyl alcohol solution.

As follows by molding in such scheme, step 2:

Under the pressure of 10～12MPa, the composite granule adding binding agent is pressed into a diameter of 12mm, thickness 1～1.5mm Disk.

By such scheme, described Ba_0.4Sr_0.6TiO₃It is prepared as follows:

By Ba_0.4Sr_0.6TiO₃Stoichiometric proportion be equipped with raw material, weigh oxalic acid dihydrate, add ethanol and deionized water, configure 1 Number solution, C₄H₆BaO₄、C₄H₆O₄Sr·1/2H₂O, deionized water and PEG6000 configure No. 2 solution；

No. 1 solution adds C₁₆H₃₆O₄Ti and C₅H₈O₂Configuration titanium oxyoxalate acid solution, is uniformly mixed at 55 DEG C, then Uniformly mixing with No. 2 solution, regulation pH is 3.00 ± 0.05, insulated and stirred reaction 2h；

By product sucking filtration, clean, dry after levigate obtain presoma, obtain nanometer in 850～900 DEG C of pre-burnings 2～3h Ba_0.4Sr_0.6TiO₃Superfine powder.

The invention has the beneficial effects as follows:

The present invention is by Ba_0.4Sr_0.6TiO₃Carry out diverse location micro ion replacement, Al replace Ti at a low price, by Nd high price Replace Ba, make pottery be internally formed the strongest interfacial polarization, produce giant dielectric phenomenon, simultaneously donor doping and the phase of acceptor doping Under interaction, limit the motion of electronics to a certain extent, reduce the high loss individually mixing different ions and produce, obtain Huge dielectric constant Ba_0.4Sr_0.6TiO₃Ceramic material (test scope the temperature range of-57～450 DEG C, 2 × 10^-5～1MHz Frequency range).

Nd, Al codope that the present invention provides replaces Ba_0.4Sr_0.6TiO₃Giant dielectric ceramic dielectric constant is high, dielectric constant temperature Degree good stability, keeps huge dielectric constant in the widest frequency range, and preparation method is simple, reproducible, and yield rate is high, Need not extra atmosphere assisted sintering, it is easy to produce.If the value of x is 0.005, when the value of y is 0.005, pottery material Material dielectric constant under 1kHz when room temperature (25 DEG C) is 34904, and dielectric loss is 0.08667, and dielectric constant is the widest Within the temperature range of vary less, simultaneously dielectric loss within the scope of the widest temperature≤0.05.By changing the difference of Nd, Al Doping content, can regulate and control the dielectric properties of this material system.

Accompanying drawing explanation

The XRD figure spectrum of Fig. 1: embodiment 1 product；

The scanning electron microscope collection of illustrative plates of Fig. 2: embodiment 1 product；

The grain size distribution figure of Fig. 3: embodiment 1 product；

The complex impedance collection of illustrative plates of Fig. 4: embodiment 1 product；

The dielectric and magnetic figure of Fig. 5: embodiment 1 product；

Dielectric constant with temperature change curve during Fig. 6: embodiment 1 product 1kHz, 10kHz, 100kHz, 1MHz；

During Fig. 7: embodiment 1 product 1kHz, 10kHz, 100kHz, 1MHz, dielectric loss varies with temperature curve；

The dielectric relaxation frequency of Fig. 8: embodiment 1 product and the Arrhenius matching collection of illustrative plates of temperature relation；

The dielectric thermogram of Fig. 9: comparative example 1 product；

The dielectric thermogram of Figure 10: comparative example 2 product.

Detailed description of the invention

In order to be more fully understood that the present invention, it is further elucidated with present disclosure below in conjunction with embodiment and accompanying drawing, but the present invention Content is not limited solely to the following examples.

Embodiment 1

0.005Nd₂O₃-0.005Al₂O₃-Ba_0.4Sr_0.6TiO₃The preparation method of represented ceramic material, specifically comprises the following steps that

1) Ba is prepared_0.4Sr_0.6TiO₃Nano-powder

By Ba_0.4Sr_0.6TiO₃Stoichiometric proportion be equipped with raw material, weigh oxalic acid dihydrate, add ethanol and deionized water, configure 1# Solution, C₄H₆BaO₄、C₄H₆O₄Sr·1/2H₂O, deionized water and PEG6000 configure 2# solution, add in 1# solution C₁₆H₃₆O₄Ti and C₅H₈O₂Configuration titanium oxyoxalate acid solution, stirring in water bath at 55 DEG C, more uniformly mix with 2# solution, adjust Solution PH processed is 3.00 ± 0.05, and heating in water bath also stirs 2h, afterwards mixed solution is carried out sucking filtration, and clear with deionized water Wash 3～5 times, levigate after drying obtain presoma, obtain nano ultrafine powders body at 900 DEG C of pre-burning 2h.

2) ceramic composite powder is prepared

Weigh Ba_0.4Sr_0.6TiO₃Nano-powder 10g, weighs Nd by proportioning₂O₃And Al₂O₃, raw mixture is loaded ball grinder In, adding zirconium ball and dehydrated alcohol, compound, dehydrated alcohol, the mass ratio of zirconium ball are 1:5:14.After ball milling 24 hours, point From zirconium ball, being put in drying baker by mixture slurry and dry, drying baker temperature is set to 100 DEG C and is dried 12 hours.

3) ceramic body is prepared

Add binding agent through the dried composite granule of ball milling carry out pelletize and sieve, obtain the spherical powder with certain particle size grating Grain.The specifically comprising the following steps that of this process use the poly-vinyl alcohol solution that concentration is 5% for preparing as binding agent, according to 1g Powder adds the ratio of 2 binding agents and is ground in three times, and the powder after grinding obtains having certain grain after crossing the sieve of 80 mesh The spherical powder of degree grating.

Weigh 0.4g granulation powder every time, put in mould, obtain a diameter of 12mm, thickness 1～1.5mm through dry-pressing formed Disk.Ceramic body after molding need to get rid of polyvinyl alcohol colloid before sintering, and the actual temp system of binder removal is as follows: in Muffle Stove rise to 600 DEG C according to the heating rate of 1 DEG C/min and is incubated 120min, naturally cooling to room temperature.

4) high temperature sintering

The ceramic body being drained through glue is placed in high temperature furnace the process that is sintered, it is not necessary to special atmosphere assisted sintering.The tool of sintering Temperature system is: is first warming up to 1000 DEG C with the heating rate of 3 DEG C/min, is then warming up to the heating rate of 2 DEG C/min 1360 DEG C and be incubated 1 hour, naturally cool to room temperature with stove.

The XRD figure of the present embodiment product is as shown in Figure 1.As seen from Figure 1, the principal crystalline phase of the ceramics sample of sintering is cube , there is not dephasign in perovskite structure, illustrates that a cube Ba is entered in Nd and Al solid solution completely_0.4Sr_0.6TiO₃In crystal.

The scanning electron microscope collection of illustrative plates of the present embodiment product is as shown in Figure 2.Fig. 3 is the crystal grain chi of corresponding huge dielectric constant ceramic material Very little scattergram, crystal grain distribution fine uniform, utilizing Image Pro plus computed in software to go out average grain size is 1.28 μm.

The complex impedance collection of illustrative plates of the present embodiment product is as shown in Figure 4.It can be seen that carry out with two different size of impedance circles Matching, the response process of little impedance circle correspondence crystal grain, the response process of big impedance circle correspondence crystal boundary, can make pottery with side light Ceramic material crystal grain is widely different with the electrology characteristic of crystal boundary.

The dielectric and magnetic figure of the present embodiment product is as shown in Figure 5.As seen from the figure, ceramics sample is in 0.02～100kHz frequency In the range of dielectric constant be all higher than 15000,100 DEG C, 150 DEG C, 200 DEG C time be situated between frequency stability preferable.

The dielectric temperature collection of illustrative plates of the present embodiment product is as shown in Figure 6 and Figure 7.Ceramics sample is in the range of-57～450 DEG C, and dielectric is normal Number > 22000, wherein when room temperature (25 DEG C), the dielectric constant under 1kHz is 34904, and dielectric loss is 0.08667.Fig. 6 Region represented by middle dotted line is 102～426 DEG C, when frequency is 1kHz, and dielectric constant with temperature in the range of 102～426 DEG C Rate of change is less than ± 15%, the temperature that is situated between good stability；In Fig. 7, the region represented by dotted line is 57～188 DEG C, when frequency is 1kHz, In the range of 57～188 DEG C, dielectric loss is less than 0.005.

The present embodiment product the dielectric relaxation frequency and temperature relation Arrhenius matching collection of illustrative plates as shown in Figure 8.Fig. 8 is root Calculating gained numeric renderings according to the loss peak of Fig. 7 to form, being calculated conductivity activation energy is 0.482eV.

Embodiment 2

The present embodiment provides 0.005Nd₂O₃-0.01Al₂O₃-Ba_0.4Sr_0.6TiO₃The preparation method of represented ceramic material, removes down Stating outside difference, remaining step is same as in Example 1:

Step 1 in embodiment 1) in, after oxalate coprecipitation method prepares presoma, obtain nanometer at 850 DEG C of pre-burning 2.5h Superfine powder.

Step 2 in embodiment 1) in, weigh Ba_0.4Sr_0.6TiO₃Nano-powder 10g, weighs Nd by proportioning₂O₃And Al₂O₃。 During wet ball-milling, compound, dehydrated alcohol, the mass ratio of zirconium ball are 1:5:10, and ball milling is after 25 hours, and separating zirconium ball, by mixing Thing slurry is put in drying baker and is dried, and drying baker temperature is set to 100 DEG C and is dried 15 hours.

Step 4 in embodiment 1) in, sintering temperature is set to 1400 DEG C and is incubated 1 hour.

The SNT of preparation_0.006Ceramics sample, has huge dielectric constant and low-dielectric loss, and when 25 DEG C, the dielectric under 1kHz is normal Number and dielectric loss are respectively 35479 and 0.09005.

Embodiment 3

The present embodiment provides 0.005Nd₂O₃-0.005Al₂O₃-Ba_0.4Sr_0.6TiO₃The preparation method of represented ceramic material, removes down Stating outside difference, remaining step is same as in Example 1:

Step 1 in embodiment 1) in, after oxalate coprecipitation method prepares presoma, obtain nanometer at 850 DEG C of pre-burning 3h and surpass Fine powder body.

Step 2 in embodiment 1) in, weigh Ba_0.4Sr_0.6TiO₃Nano-powder 10g, weighs Nd by proportioning₂O₃And Al₂O₃。 During wet ball-milling, compound, dehydrated alcohol, the mass ratio of zirconium ball are 1:4:12, and ball milling is after 30 hours, and separating zirconium ball, by mixing Thing slurry is put in drying baker and is dried, and drying baker temperature is set to 100 DEG C and is dried 12 hours.

Step 4 in embodiment 1) in, sintering temperature is set to 1360 DEG C and is incubated 4 hours.

The 0.005Nd of preparation₂O₃-0.005Al₂O₃-Ba_0.4Sr_0.6TiO₃Ceramics sample, has huge dielectric constant and low-dielectric loss, When 25 DEG C, the dielectric constant under 1kHz and dielectric loss are respectively 29419 and 0.0973.

Comparative example 1

Step 1 by embodiment 1) prepare Ba_0.4Sr_0.6TiO₃Nano-powder, by Ba_0.4Sr_0.6TiO₃And Nd₂O₃According to 0.005Nd₂O₃-Ba_0.4Sr_0.6TiO₃Proportioning mixing, with dehydrated alcohol as dispersant, by wet ball-milling method mixing and ball milling post-drying, Add 5% poly-vinyl alcohol solution pelletize and sieve.The pottery that a diameter of 12mm, thickness are 1～1.5mm is prepared through dry-pressing formed Base substrate.By its in high temperature furnace 1360 DEG C be incubated 4 hours, obtain sintering 0.005Nd₂O₃-Ba_0.4Sr_0.6TiO₃Ceramic material, In whole preparation process, NM part is all identical with the condition of embodiment 1.To preparation 0.005Nd₂O₃-Ba_0.4Sr_0.6TiO₃Pottery carries out dielectric properties test, its dielectric temperature compose as it is shown in figure 9, obtained by figure: 25 DEG C, Under the conditions of 1kHz, its dielectric constant and dielectric loss are respectively 3788 and 0.224, and dielectric properties are significantly lower than of the present invention Nd, Al codope replaces Ba_0.4Sr_0.6TiO₃Giant dielectric ceramic material.

Comparative example 2

Step 1 by embodiment 1) prepare Ba_0.4Sr_0.6TiO₃Nano-powder, by Ba_0.4Sr_0.6TiO₃And Al₂O₃According to 0.005 Al₂O₃-Ba_0.4Sr_0.6TiO₃Proportioning mixing, with dehydrated alcohol as dispersant, by wet ball-milling method mixing and ball milling post-drying, add 5% poly-vinyl alcohol solution pelletize is also sieved.The ceramic body that a diameter of 12mm, thickness are 1～1.5mm is prepared through dry-pressing formed. By its in high temperature furnace 1360 DEG C be incubated 4 hours, obtain sintering 0.005Nd₂O₃-Ba_0.4Sr_0.6TiO₃Ceramic material, whole In preparation process, NM part is all identical with the condition of embodiment 1.0.005Nd to preparation₂O₃-Ba_0.4Sr_0.6TiO₃Pottery Carrying out dielectric properties test, its dielectric temperature is composed as shown in Figure 10.25 DEG C, under the conditions of 1kHz, its dielectric constant and dielectric are damaged Consumption is respectively 665 and 0.01211, and dielectric constant replaces Ba significantly lower than Nd, Al codope of the present invention_0.4Sr_0.6TiO₃Huge Dielectric ceramic material.

Comparative example 3

By Ba_0.4Sr_0.6TiO₃、Nd₂O₃、Al₂O₃According to 0.005Nd₂O₃-0.005Al₂O₃-Ba_0.4Sr_0.6TiO₃Stoichiometric proportion Proportioning mixes, and with dehydrated alcohol as dispersant, by wet ball-milling method mixing and ball milling post-drying, adds 5% poly-vinyl alcohol solution pelletize And sieve.The ceramic body that a diameter of 12mm, thickness are 1～1.5mm is prepared through dry-pressing formed.By its in high temperature furnace 1360 DEG C It is incubated 8 hours, obtains the 0.005Nd of sintering₂O₃-0.005Al₂O₃-Ba_0.4Sr_0.6TiO₃Ceramic material, in whole preparation process NM part is all identical with the condition of embodiment 1.To preparation ceramics sample carry out dielectric properties test, obtain: 25 DEG C, Under the conditions of 1kHz, its dielectric constant and dielectric loss are respectively 26605 and 0.1243, dielectric constant less than Nd of the present invention, Al codope replaces Ba_0.4Sr_0.6TiO₃Giant dielectric ceramic material, dielectric loss replaces higher than Nd, Al codope of the present invention Ba_0.4Sr_0.6TiO₃Giant dielectric ceramic material.Further experimental exploration can obtain, along with temperature retention time during sintering more than 4h, Nd, Al codope replaces Ba_0.4Sr_0.6TiO₃The dielectric constant of ceramic material has obvious reduction trend, and dielectric loss exceedes 0.1。

Comparative example 4

By Ba_0.4Sr_0.6TiO₃、Nd₂O₃、Al₂O₃According to 0.005Nd₂O₃-0.0025Al₂O₃-Ba_0.4Sr_0.6TiO₃Stoichiometry Mix than proportioning, with dehydrated alcohol as dispersant, by wet ball-milling method mixing and ball milling post-drying, add 5% poly-vinyl alcohol solution and make Grain also sieves.The ceramic body that a diameter of 12mm, thickness are 1～1.5mm is prepared through dry-pressing formed.By it in high temperature furnace 1360 DEG C of insulation 1h, sintering obtains 0.005Nd₂O₃-0.0025Al₂O₃-Ba_0.4Sr_0.6TiO₃Ceramic material, in whole preparation process In NM part all identical with the condition of embodiment 1.The ceramics sample of preparation is carried out dielectric properties test, obtains: 25 DEG C, under the conditions of 1kHz, its dielectric constant and dielectric loss are respectively 16731 and 0.2824, and dielectric constant is significantly lower than this Invent described Nd, Al codope and replace Ba_0.4Sr_0.6TiO₃Giant dielectric ceramic material, dielectric loss is apparently higher than of the present invention Nd, Al codope replaces Ba_0.4Sr_0.6TiO₃Giant dielectric ceramic material.Further experimental exploration can obtain, and works as Al₂O₃Mole When volume is less than 0.005, Nd, Al codope replaces Ba_0.4Sr_0.6TiO₃The dielectric constant of ceramic material occurs in that reduction drastically, Significantly increasing occurs in dielectric loss.

Detailed description of the invention is to by whether be doped, and uses different component doping, the difference of temperature retention time, the pottery of preparation Ceramic material has carried out the investigation of electrical property, and experimental result contrast shows: Nd, Al codope of the present invention replaces Ba_0.4Sr_0.6TiO₃ The ceramics sample that the most available dielectric properties of pottery sintering in atmosphere are excellent.

Claims (7)

1. Nd, Al codope replaces Ba_0.4Sr_0.6TiO₃Giant dielectric pottery, it is characterised in that replaced Ti by Al at a low price, Replaced Ba by Nd high price, use xNd₂O₃-yAl₂O₃-Ba_0.4Sr_0.6TiO₃Represent, 0.005≤x≤0.01 in formula, 0.005≤y≤0.01.

2. Nd, Al codope replaces Ba as claimed in claim 1_0.4Sr_0.6TiO₃Giant dielectric pottery, it is characterised in that described Nd, Al codope replaces Ba_0.4Sr_0.6TiO₃Giant dielectric ceramic material is by Ba_0.4Sr_0.6TiO₃、Nd₂O₃、Al₂O₃Press xNd₂O₃-yAl₂O₃-Ba_0.4Sr_0.6TiO₃The ceramic body that is mixed of stoichiometric proportion 1:x:y in 1360～1400 DEG C of insulations Sinter and obtain.

3. Nd, Al codope described in claim 1 replaces Ba_0.4Sr_0.6TiO₃The preparation method of giant dielectric pottery, its feature exists In comprising the following steps:

1) by Ba_0.4Sr_0.6TiO₃、Nd₂O₃And Al₂O₃Mixing, adds ball milling after dispersant, obtains composite granule after drying；

2) composite granule is added binding agent pelletize and sieve, molding, then binder removal obtains ceramic body；

3) by ceramic body heat preservation sintering 1～4h at 1360～1400 DEG C, with stove natural cooling.

4. Nd, Al codope replaces Ba as claimed in claim 3_0.4Sr_0.6TiO₃The preparation method of giant dielectric pottery, its feature Being in step 1 that dispersant is dehydrated alcohol, ball-milling medium is zirconium ball；Wherein compound: dehydrated alcohol: zirconium ball is in mass ratio For 1:(4～5): (10～14) carry out ball milling.

5. Nd, Al codope replaces Ba as claimed in claim 3_0.4Sr_0.6TiO₃The preparation method of giant dielectric pottery, its feature Being in step 2 that pelletize sticks with glue agent is poly-vinyl alcohol solution.

6. Nd, Al codope replaces Ba as claimed in claim 3_0.4Sr_0.6TiO₃The preparation method of giant dielectric pottery, its feature It is in step 2 that molding is as follows:

Under the pressure of 10～12MPa, the composite granule adding binding agent is pressed into a diameter of 12mm, thickness 1～1.5mm Disk.

7. Nd, Al codope replaces Ba as claimed in claim 3_0.4Sr_0.6TiO₃The preparation method of giant dielectric pottery, its feature It is described Ba_0.4Sr_0.6TiO₃It is prepared as follows:

By Ba_0.4Sr_0.6TiO₃Stoichiometric proportion be equipped with raw material, weigh oxalic acid dihydrate, add ethanol and deionized water, configure 1 Number solution, C₄H₆BaO₄、C₄H₆O₄Sr·1/2H₂O, deionized water and PEG6000 configure No. 2 solution；

No. 1 solution adds C₁₆H₃₆O₄Ti and C₅H₈O₂Configuration titanium oxyoxalate acid solution, is uniformly mixed at 55 DEG C, then Uniformly mixing with No. 2 solution, regulation pH is 3.00 ± 0.05, insulated and stirred reaction 2h；

By product sucking filtration, clean, dry after levigate obtain presoma, obtain nanometer in 850～900 DEG C of pre-burnings 2～3h Ba_0.4Sr_0.6TiO₃Superfine powder.