[go: up one dir, main page]

CN118930245A - A ZnBiMnGeO-based varistor ceramic material and preparation method thereof - Google Patents

A ZnBiMnGeO-based varistor ceramic material and preparation method thereof Download PDF

Info

Publication number
CN118930245A
CN118930245A CN202411066278.9A CN202411066278A CN118930245A CN 118930245 A CN118930245 A CN 118930245A CN 202411066278 A CN202411066278 A CN 202411066278A CN 118930245 A CN118930245 A CN 118930245A
Authority
CN
China
Prior art keywords
ceramic material
znbimngeo
zno
green body
varistor ceramic
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202411066278.9A
Other languages
Chinese (zh)
Inventor
赵鸣
陈苗苗
刘卓承
崔承昊
陈华
杜永胜
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Inner Mongolia University of Science and Technology
Original Assignee
Inner Mongolia University of Science and Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Inner Mongolia University of Science and Technology filed Critical Inner Mongolia University of Science and Technology
Priority to CN202411066278.9A priority Critical patent/CN118930245A/en
Publication of CN118930245A publication Critical patent/CN118930245A/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/453—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zinc, tin, or bismuth oxides or solid solutions thereof with other oxides, e.g. zincates, stannates or bismuthates
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/638—Removal thereof
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3262—Manganese oxides, manganates, rhenium oxides or oxide-forming salts thereof, e.g. MnO
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3287—Germanium oxides, germanates or oxide forming salts thereof, e.g. copper germanate
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3298—Bismuth oxides, bismuthates or oxide forming salts thereof, e.g. zinc bismuthate
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/60—Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
    • C04B2235/602—Making the green bodies or pre-forms by moulding
    • C04B2235/6025—Tape casting, e.g. with a doctor blade
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
    • C04B2235/6562—Heating rate
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
    • C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
    • C04B2235/6567—Treatment time
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/74—Physical characteristics
    • C04B2235/78—Grain sizes and shapes, product microstructures, e.g. acicular grains, equiaxed grains, platelet-structures
    • C04B2235/786—Micrometer sized grains, i.e. from 1 to 100 micron

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Compositions Of Oxide Ceramics (AREA)
  • Thermistors And Varistors (AREA)

Abstract

本发明涉及一种ZnBiMnGeO基压敏陶瓷材料及制备方法。该材料由O、Zn、Bi、Mn和Ge五种元素组成，在Zn、Bi、Mn和Ge四种元素总摩尔数为100％的条件下，Bi、Mn和Ge三种元素的摩尔百分比分别为：0.5～5％、1～4％、0.05～0.5％，其余为Zn元素。制备时采用传统固相烧结工艺，烧结温度875～1000℃，保温时间1～6小时，得到的材料压敏电压为120V/mm～340V/mm，非线性系数α大于40，漏电流密度JL小于10μA/cm2。本发明的ZnO基压敏陶瓷，组分简单，性能良好，漏电流小，可减少ZnO基压敏电阻在使用过程中的无功损耗，有利于降低ZnO基压敏电阻的生产及应用成本。

The present invention relates to a ZnBiMnGeO-based varistor ceramic material and a preparation method thereof. The material is composed of five elements, O, Zn, Bi, Mn and Ge. Under the condition that the total molar number of the four elements Zn, Bi, Mn and Ge is 100%, the molar percentages of the three elements Bi, Mn and Ge are respectively 0.5-5%, 1-4%, 0.05-0.5%, and the rest is Zn element. The traditional solid phase sintering process is adopted in the preparation, the sintering temperature is 875-1000°C, the holding time is 1-6 hours, and the obtained material has a varistor voltage of 120V/mm-340V/mm, a nonlinear coefficient α greater than 40, and a leakage current density J L less than 10μA/cm 2. The ZnO-based varistor ceramic of the present invention has simple components, good performance, small leakage current, can reduce the reactive power loss of the ZnO-based varistor during use, and is conducive to reducing the production and application costs of the ZnO-based varistor.

Description

ZnBiMnGeO-based pressure-sensitive ceramic material and preparation method thereof
Technical Field
The invention relates to the technical field of ceramic preparation, in particular to ZnBiMnGeO-base pressure-sensitive ceramic material and a preparation method thereof.
Background
The ZnO-based voltage-sensitive ceramic is a nonlinear resistance material with internal resistance which can repeatedly change suddenly according to the voltage applied relative to a certain critical voltage (namely, the voltage-sensitive voltage). When the applied voltage is lower than the voltage-sensitive voltage, the internal electrode of the ZnO-based voltage-sensitive ceramic is very large, similar to an insulating state body; when the high applied voltage is higher than the voltage sensitive voltage, the internal resistance thereof is instantaneously reduced to an approximately conductive state. Based on the characteristic, a ZnO-based varistor made of ZnO voltage-sensitive ceramic is often connected into a circuit in parallel with a protected circuit or device to prevent damage to the protected circuit or device by abnormal surge voltage. At present, the application range of the ZnO-based piezoresistor already covers almost all electronic and electric fields such as low voltage, medium voltage and high voltage, and becomes an abnormal voltage surge protection device with the largest worldwide consumption.
All ZnO-based pressure-sensitive ceramics take ZnO powder as a main raw material. On the basis, Bi2O3、V2O5、Pr2O3(Pr6O11)、Cr2O3、Sb2O3、MnO2、Co2O3、Nb2O5、CaO, and various dopants such as various rare earth oxides are further added into the common high-performance ZnO-based pressure-sensitive ceramics, so that most of the components of the high-performance ZnO-based pressure-sensitive ceramics are often up to 6 or more. This multicomponent nature of ZnO based pressure sensitive ceramics undoubtedly aggravates the impact of the entire varistor industry on increasingly scarce natural resources.
Whatever process is adopted for preparation, the ZnO powder and various doping can be changed into pressure-sensitive ceramics only through a high-temperature sintering process. Most high performance ZnO based pressure sensitive ceramics have sintering temperatures above 1000 ℃, and some even higher, up to 1200 ℃. To meet such high sintering temperatures, electronics factories producing piezoresistors are not only more costly high-temperature sintering equipment, but also necessarily consume more electrical energy during production. In the process of producing the low-voltage sheet type piezoresistor by adopting a laminated cofiring process, the inner electrode must adopt alloys with high noble metal content such as Pt or Pd, but cannot adopt low-melting-point base metals such as Cu (melting point 1083 ℃), and the cost is higher. These factors are the main reasons for hindering energy conservation and consumption reduction of the whole ZnO-based pressure-sensitive ceramic industry and realizing green production.
In addition, when the ZnO-based piezoresistor is applied to an actual electronic circuit as an abnormal voltage surge protection device, even if the external field voltage born by the ZnO-based piezoresistor is smaller than the voltage-sensitive voltage of the ZnO-based piezoresistor, certain current can flow in the ZnO-based piezoresistor. Such a current is called leakage current, which is simply referred to as leakage current, and its magnitude is expressed by leakage current density. Therefore, the leakage current is a main cause of reactive power loss of the ZnO-based varistor in practical application. In order to reduce reactive power loss of the ZnO-based varistor in the practical application process, znO-based voltage-sensitive ceramics with as low leakage current as possible are required to be adopted.
Disclosure of Invention
Aiming at the existing problems, the invention provides a ZnBiMnGeO pressure-sensitive ceramic material taking GeO 2 as a main doping modification substance and a preparation method thereof.
The technical scheme of the invention is as follows:
ZnBiMnGeO simple-component pressure-sensitive ceramic comprises the following components in percentage by mole under the condition that the total molar content of four elements of Zn, bi, mn and Ge is 100 percent: bi is 0.5-5%, mn is 1-4%, ge is 0.05-0.5%.
The raw materials are oxides of four metal elements Zn, bi, mn and Ge, or compounds such as carbonate, nitrate, acetate or hydroxide which can be decomposed into the metal oxides, or pre-synthesized products which take the oxides of the four elements or other compounds as raw materials, for example Bi 2O3·2Mn2O3 or 6Bi 2O3·GeO2 type oxide solid solutions synthesized by the pre-heating reaction of Bi 2O3 and Mn 2O3 or GeO 2.
The preparation method of the ZnBiMnGeO-based pressure-sensitive ceramic material comprises the following steps:
(1) Weighing ZnO, bi 2O3、MnCO3 and GeO 2 raw materials according to the molar ratio of Zn, bi, mn and Ge in the pressure-sensitive ceramic material, and preparing a ceramic green body by adopting a traditional solid phase process;
(2) Sintering the biscuit body after glue discharging to 875-1000 ℃ at a heating rate of 2-15 ℃/min, preserving heat for 1-6 hours, and finally naturally cooling to room temperature along with a furnace to obtain the pressure-sensitive ceramic material.
Preferably, the green body after glue discharging is heated to 975 ℃ at a heating rate of 4 ℃/min, sintered and kept for 3 hours.
The pressure sensitive ceramic can also adopt the existing ceramic synthesis process by casting molding method.
The invention has the beneficial effects that:
(1) The pressure-sensitive ceramic material disclosed by the invention takes ZnO as a main component, wherein the ZnO content is more than 90%, and only three doping components Bi, mn and Ge are added on the basis of ZnO, so that the ZnBiMnGeO-based pressure-sensitive ceramic material is obtained.
(2) The invention adopts the traditional solid phase synthesis process, geO 2 and Bi 2O3 in the raw materials can start to form eutectic liquid phase at about 882 ℃, thereby improving the liquid phase generation amount in the sintering process and enabling the ceramic to be sintered at the low temperature of 975 ℃. The sintering temperature (975 ℃) is significantly lower than the melting point 1083℃of Cu. The low-temperature sintering characteristic can reduce the sintering cost in the preparation process of the single ZnO-based piezoresistor, and can also lead manufacturers to prepare the low-voltage laminated ZnO-based piezoresistor by taking ZnBiMnGeO-based pressure-sensitive ceramic of the invention as a raw material and using Cu and other base metals to replace Pt or Ag-Pd alloy with higher melting point and price as an inner electrode.
(3) The cooling after sintering adopts a natural cooling method, and the slow cooling can not only release the stress on the crystal boundary in the ZnO-based pressure-sensitive ceramic, but also ensure that the doped ions dissolved into ZnO crystal grains and the eutectic liquid phase at high temperature are desolventized to the ZnO crystal boundary for a longer time, so that the obtained ZnO-based ceramic has better pressure-sensitive characteristic.
(4) According to the invention, the Ge is doped on the ZnO crystal boundary to form donor doping and zinc vacancy defects to strengthen the crystal boundary potential barrier, so that the performance of ZnBiMnGeO pressure-sensitive ceramic is optimized;
(5) The ZnBiMnGeO pressure-sensitive ceramic has excellent electrical performance, the pressure-sensitive voltage is 120-340V/mm, the nonlinear coefficient alpha is more than 40, and the leakage current density J L<10μA/cm2.
(6) Under the situation that natural resources and energy resources are increasingly deficient at present, the invention provides the ZnO-based pressure-sensitive material which simultaneously meets the requirements of three aspects of component simplification, sintering low temperature and leakage current low value, and provides a new idea for the green sustainable development of the whole piezoresistor industry.
(7) The novel pressure-sensitive ceramic material is not only suitable for the split ZnO-based piezoresistor in the high-medium voltage field, but also suitable for the chip type laminated ZnO-based piezoresistor in the low-voltage application field, and is an ideal substitute for the ZnO piezoresistor ceramic material of various systems with the sintering temperature higher than 1000 ℃. The related products can be used as high-voltage power transmission and lightning arresters, overvoltage protectors of medium-voltage automobiles, overvoltage protectors of integrated circuits in the low-voltage field and the like, and have very wide market prospect.
Drawings
FIG. 1 is an E-J curve of ZnBiMnGeO pressure sensitive ceramics according to example 1;
FIG. 2 is an E-J curve of ZnBiMnGeO pressure sensitive ceramics according to example 2;
FIG. 3 is an E-J curve of ZnBiMnGeO pressure sensitive ceramics according to example 3.
Detailed Description
The invention is further illustrated by the following examples, which are not intended to be limiting.
Table 1 ceramic powder formulations (mol%) for the examples
Raw materials ZnO Bi2O3 MnCO3 GeO2
Example 1 97.44 0.50 2.00 0.06
Example 2 97.40 0.50 2.00 0.10
Example 3 97.35 0.50 2.00 0.15
Example 1: a preparation method of ZnBiMnGeO-based high-performance pressure-sensitive ceramic material comprises the following steps:
(1) Accurately weighing according to the formula of the ceramic powder, wherein the mole percentages of the raw materials are as follows: znO 97.44, bi 2O30.5、MnCO3 2 and GeO 2 0.06.06;
The ceramic green body is prepared by adopting the traditional solid phase process, and the specific process is as follows: ball milling all raw materials for 12h by adopting a planetary ball mill and adopting zirconia balls and absolute ethyl alcohol as ball milling media; putting the ball-milled raw material slurry into an oven at 80 ℃ for drying for 24 hours; mixing the dried raw materials with a proper amount of polyvinyl alcohol with the concentration of 5%, granulating, and compressing into a green body with the diameter of 12mm and the thickness of about 1.2 mm; heating the green body to 500 ℃ at a heating rate of 1 ℃/min, and preserving heat for 1 hour to perform glue discharging (namely discharging polyvinyl alcohol);
(2) Sintering the green body after glue discharging to 975 ℃ at a heating rate of 4 ℃/min, preserving heat for 3 hours, and naturally cooling to room temperature along with a furnace to obtain the zinc oxide-based pressure-sensitive ceramic sample.
The upper and lower surfaces of the sintered sample were polished to prepare silver electrodes, and the E-J curves were measured, as shown in FIG. 1. FIG. 1 shows that the nonlinear transition of the E-J curve of the sample from the low current density region to the high current density region exhibits a "knee" trend that is typical of piezoresistors; whereas the "knee" has been approximated by a right angle, indicating that the sample has good nonlinear electrical properties. Based on this, the nonlinear coefficient α, the voltage-sensitive voltage E b, and the leakage current density J L of the sample to be measured were calculated, respectively, and the results are shown in table 2.
TABLE 2 Performance index of pressure sensitive ceramics of example 1
Table 2 shows that the product of example 1 has a nonlinear coefficient α as high as 48.62, a voltage-sensitive voltage of 338.10V/mm and an average grain diameter of 7.47 μm; meanwhile, the leakage current density was only 6.09. Mu.A/cm 2.
Example 2: a preparation method of ZnBiMnGeO-based pressure-sensitive ceramic material comprises the following steps:
(1) Accurately weighing according to the formula of the ceramic powder, wherein the mole percentages of the raw materials are as follows: : znO 97.40, bi 2O30.5、MnCO3 2, and GeO 2 0.1.1;
Adopting a traditional solid-phase process to prepare a ceramic green body, specifically adopting a planetary ball mill, ball milling zirconia balls and absolute ethyl alcohol as ball milling media, and ball milling all raw materials for 12 hours; putting the ball-milled raw material slurry into an oven at 80 ℃ for drying for 24 hours; mixing the dried raw materials with a proper amount of polyvinyl alcohol with the concentration of 5%, granulating, and compressing into a green body with the diameter of 12mm and the thickness of about 1.2 mm; heating the green body to 500 ℃ at a heating rate of 1 ℃/min, and preserving heat for 1 hour to perform glue discharging (namely discharging polyvinyl alcohol);
(2) Sintering the green body after glue discharging to 975 ℃ at a heating rate of 4 ℃/min, preserving heat for 3 hours, and naturally cooling to room temperature along with a furnace; obtaining the zinc oxide-based pressure sensitive ceramic.
The upper and lower surfaces of the sintered sample were polished to prepare silver electrodes, and the E-J curves were measured as shown in FIG. 2. FIG. 2 shows that the non-linear transition of the E-J curve of the sample from the low current density region to the high current density region also exhibits a "knee" trend that is typical of piezoresistors; whereas the "knee" has been approximated by a right angle, indicating that the sample has good nonlinear electrical properties. Based on the above, the nonlinear coefficient alpha, the voltage-sensitive voltage E b and the leakage current density J L of the tested sample are calculated respectively, and the results are summarized in Table 3.
TABLE 3 Performance index of pressure sensitive ceramics of example 2
The data in Table 3 shows that as the GeO 2 doping level increases, the average grain size increases to 7.63 μm and the pressure sensitive voltage drops to 201.61V/mm; the nonlinear coefficient is slightly reduced and still greater than 40; the leakage current density was at a low level of 7.28. Mu.A/cm 2.
Example 3: a preparation method of ZnBiMnGeO-based pressure-sensitive ceramic material comprises the following steps:
(1) Accurately weighing according to the formula of the ceramic powder, wherein the mole percentages of the raw materials are as follows: : znO 97.35, bi 2O30.5、MnCO3 2 and GeO 2 0.15.15;
The ceramic green body is prepared by adopting the traditional solid phase process, and the specific process is as follows: ball milling all raw materials for 12h by adopting a planetary ball mill and adopting zirconia balls and absolute ethyl alcohol as ball milling media; putting the ball-milled raw material slurry into an oven at 80 ℃ for drying for 24 hours; mixing the dried raw materials with a proper amount of polyvinyl alcohol with the concentration of 5%, granulating, and compressing into a green body with the diameter of 12mm and the thickness of about 1.2 mm; heating the green body to 500 ℃ at a heating rate of 1 ℃/min, and preserving heat for 1 hour to perform glue discharging (namely discharging polyvinyl alcohol);
(2) Sintering the green body after glue discharging to 975 ℃ at a heating rate of 4 ℃/min, preserving heat for 3 hours, and naturally cooling to room temperature along with a furnace; obtaining the zinc oxide-based pressure sensitive ceramic.
The upper and lower surfaces of the sintered sample were polished to prepare silver electrodes, and the E-J curves were measured, as shown in FIG. 3. FIG. 3 shows that the non-linear transition of the E-J curve of the sample from the low current density region to the high current density region also exhibits a "knee" trend that is typical of piezoresistors; whereas the "knee" has been approximated by a right angle, indicating that the sample has good nonlinear electrical properties. Based on this, the nonlinear coefficient α, the voltage-sensitive voltage E b, and the leakage current density J L of the sample to be measured were calculated, respectively, and the results are summarized in table 4.
TABLE 4 Performance index of pressure sensitive ceramics of example 3
Table 4 shows that as the GeO2 doping amount increases, the average grain size increases to 7.80 μm and the pressure sensitive voltage decreases to 129.24V/mm. The non-linear coefficient alpha can still be maintained at a higher level than 40. The leakage current density was only 8.55. Mu.A/cm 2.
The ZnO-based pressure-sensitive ceramic is prepared by adopting a solid-phase sintering process, and can be completely sintered at a low temperature of 975 ℃. The high-performance pressure-sensitive ceramic with the nonlinear coefficient of more than 40, the pressure-sensitive voltage of 100-400V/mm and the leakage current density of less than 10 mu A/cm < 2 > can be prepared by adding a very small amount of GeO2 (0.05-0.5 percent by mole percent).
The sintering temperature (975 ℃) of the process is obviously lower than the melting point 1083 ℃ of Cu. The low-temperature sintering characteristic can reduce the sintering cost in the preparation process of the ZnO-based piezoresistor, and can also enable manufacturers to prepare the low-voltage laminated ZnO-based piezoresistor by taking ZnBiMnGeO-based pressure-sensitive ceramic of the invention as a raw material and using Cu and other base metals to replace Pt or Ag-Pd alloy with higher melting point and price as an inner electrode. In summary, the high-performance ZnBiMnGeO pressure-sensitive ceramic provides a new idea for low-cost green production and application of ZnO-based piezoresistors.

Claims (5)

1.一种ZnBiMnGeO基压敏陶瓷材料，其特征在于，该材料由O、Zn、Bi、Mn和Ge五种元素组成，在Zn、Bi、Mn和Ge四种元素总摩尔含量为100％的条件下，Bi、Mn和Ge三种元素的摩尔百分比分别为：0.5～5％、1～4％、0.05～0.5％，其余为Zn元素。1. A ZnBiMnGeO-based varistor ceramic material, characterized in that the material is composed of five elements: O, Zn, Bi, Mn and Ge. Under the condition that the total molar content of the four elements Zn, Bi, Mn and Ge is 100%, the molar percentages of the three elements Bi, Mn and Ge are: 0.5-5%, 1-4%, 0.05-0.5%, respectively, and the rest is Zn element. 2.根据权利要求1所述的ZnBiMnGeO基压敏陶瓷材料，其特征在于，所述的压敏陶瓷材料的原料为Zn、Bi、Mn、Ge四种金属元素的氧化物、碳酸盐、硝酸盐、醋酸盐或氢氧化物。2. The ZnBiMnGeO-based varistor ceramic material according to claim 1 is characterized in that the raw materials of the varistor ceramic material are oxides, carbonates, nitrates, acetates or hydroxides of four metal elements: Zn, Bi, Mn and Ge. 3.一种权利要求1所述的的ZnBiMnGeO基压敏陶瓷材料的制备方法，其特征在于，按压敏陶瓷材料中Zn、Bi、Mn和Ge四种元素的摩尔比称取ZnO、Bi2O3、MnCO3和GeO2原料，然后采用传统固相工艺制备陶瓷素坯体；3. A method for preparing the ZnBiMnGeO-based varistor ceramic material according to claim 1, characterized in that ZnO, Bi2O3 , MnCO3 and GeO2 raw materials are weighed according to the molar ratio of the four elements Zn, Bi, Mn and Ge in the varistor ceramic material, and then a ceramic green body is prepared by a conventional solid phase process ; 将排胶后的素坯体以2～15℃/min的升温速率烧结至875～1000℃，并保温1-6小时，最后随炉自然冷却至室温得到压敏陶瓷材料。The debinding green body is sintered to 875-1000°C at a heating rate of 2-15°C/min, and kept at the temperature for 1-6 hours. Finally, the green body is naturally cooled to room temperature in the furnace to obtain a varistor ceramic material. 4.根据权利要求3所述的ZnBiMnGeO基压敏陶瓷材料的制备方法，其特征在于，所述的传统固相工艺制备陶瓷素坯体的方法是：将原料混合后，加入行星式球磨机，球磨12h得到粉料；将粉料放入80℃烘箱干燥24h，将粉料与适量聚乙烯醇混合，造粒，并压缩成直径为12mm的素坯体；将素坯体以1℃/min的升温速率加热至500℃，保温1小时，进行排胶。4. The method for preparing the ZnBiMnGeO-based varistor ceramic material according to claim 3 is characterized in that the method for preparing the ceramic green body by the traditional solid phase process is: after mixing the raw materials, adding them into a planetary ball mill and ball milling them for 12 hours to obtain a powder; putting the powder into an 80°C oven and drying it for 24 hours, mixing the powder with an appropriate amount of polyvinyl alcohol, granulating, and compressing it into a green body with a diameter of 12 mm; heating the green body to 500°C at a heating rate of 1°C/min, keeping it warm for 1 hour, and debinding. 5.根据权利要求3所述的ZnBiMnGeO基压敏陶瓷材料的制备方法，其特征在于，将排胶后的素坯体以4℃/min的升温速率升温至975℃，进行烧结，保温3小时。5. The method for preparing the ZnBiMnGeO-based varistor ceramic material according to claim 3, characterized in that the green body after debinding is heated to 975°C at a heating rate of 4°C/min, sintered, and kept warm for 3 hours.
CN202411066278.9A 2024-08-05 2024-08-05 A ZnBiMnGeO-based varistor ceramic material and preparation method thereof Pending CN118930245A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202411066278.9A CN118930245A (en) 2024-08-05 2024-08-05 A ZnBiMnGeO-based varistor ceramic material and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202411066278.9A CN118930245A (en) 2024-08-05 2024-08-05 A ZnBiMnGeO-based varistor ceramic material and preparation method thereof

Publications (1)

Publication Number Publication Date
CN118930245A true CN118930245A (en) 2024-11-12

Family

ID=93344190

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202411066278.9A Pending CN118930245A (en) 2024-08-05 2024-08-05 A ZnBiMnGeO-based varistor ceramic material and preparation method thereof

Country Status (1)

Country Link
CN (1) CN118930245A (en)

Similar Documents

Publication Publication Date Title
CN102020463B (en) Zinc oxide piezoresistor material and preparing method thereof
CN100412029C (en) Zinc oxide-based high potential gradient varistor ceramic material and its preparation method and application
CN101786874B (en) A process for preparing low residual voltage ZnO varistor ceramics
CN101239819B (en) Preparation method of chip type multilayer zinc oxide piezoresistor ceramic powder
CN104944935A (en) ZnO varister ceramic and preparation method thereof
CN105272208B (en) A kind of zinc oxide varistor dielectric material and preparation method thereof
CN101613199B (en) High-performance zinc oxide composite ceramic voltage dependent resistor material and preparation method
CN105859278A (en) Varistor ceramic preparation method reducing ZnO grain resistivity
CN102167579B (en) A low-temperature sintered ZnO-Bi2O3-B2O3 series varistor material and its preparation method
CN104003709A (en) Zinc oxide-based pressure-sensitive ceramic material for lightning arrester as well as preparation method and application of material
CN111029071A (en) Preparation method of medium-voltage gradient zinc oxide piezoresistor MOV chip
CN102617126A (en) Low-temperature sintered zinc oxide voltage dependent resistance material and preparation method thereof
CN102633498A (en) Low-temperature sintered zinc oxide voltage-sensitive ceramic material and preparation method thereof
CN101759431B (en) Zinc oxide piezoresistor material with low electric potential gradient and preparation method thereof
CN110372335A (en) A kind of manganese nickel aluminium cobalt-based NTC thermistor material and preparation method thereof
CN103183508A (en) NTC thermistor material as well as preparation method and application in electronic device
CN105837201A (en) Making method of low-residual voltage piezoresistor of low-resistivity ZnO crystal grains
CN110423110B (en) A kind of ultra-high nonlinear ZnO-Bi2O3 based varistor ceramics and preparation method thereof
CN118930245A (en) A ZnBiMnGeO-based varistor ceramic material and preparation method thereof
CN103910524B (en) Tin ash piezoresistive material of a kind of rare-earth oxide modified and preparation method thereof
CN110317045A (en) A kind of manganese ferronickel cobalt-based NTC thermistor material and preparation method thereof
CN110304905A (en) A kind of copper samarium is the NTC thermistor material and preparation method thereof of semiconducting
CN103387389A (en) Five-membered ZnO voltage-sensitive ceramic material having low leak current and sintering method thereof
CN100595849C (en) A low voltage/high nonlinear index chip varistor and its manufacturing method
CN106946561B (en) Y3+、Nb5+Composite donor doped ZnO pressure-sensitive ceramic and preparation method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination