阅读说明：本技术 一种耐高温真空热敏电阻器封装用玻璃陶瓷材料及其制备方法 (Glass ceramic material for packaging high-temperature-resistant vacuum thermistor and preparation method thereof ) 是由 赵岩 赵青 孔雯雯 常爱民 何东林 吴兵 于 2021-01-06 设计创作，主要内容包括：本发明涉及一种耐高温真空热敏电阻器封装用玻璃陶瓷材料及其制备方法,该材料充分利用玻璃陶瓷的性能优势,提升耐高温真空热敏电阻器的高温稳定性和耐热冲击性能,提高耐高温真空热敏电阻器的可靠性和服役寿命。同时,利用玻璃陶瓷的形成机制,可在温度900℃烧结形成玻璃陶瓷的同时实现封装成型,简化了封装工艺,提高封装质量和产品的一致性,对完成航天用户新的需求指标、研制国际先进水平的耐高温真空热敏电阻器有重要的现实意义。(The invention relates to a glass ceramic material for packaging a high-temperature-resistant vacuum thermistor and a preparation method thereof. Meanwhile, by utilizing a forming mechanism of the glass ceramic, the glass ceramic can be formed by sintering at the temperature of 900 ℃ and meanwhile can be packaged and formed, the packaging process is simplified, the packaging quality and the product consistency are improved, and the method has important practical significance for completing new requirement indexes of aerospace users and developing high-temperature-resistant vacuum thermistors of international advanced level.)

1. The glass ceramic material for packaging the high-temperature-resistant vacuum thermistor is characterized in that magnesium oxide, aluminum oxide and silicon dioxide are used as mother phase glass forming materials, barium oxide, a barium oxide and yttrium oxide mixture or a zirconium oxide and yttrium oxide mixture is doped respectively, and the specific operation is carried out according to the following steps:

a. weighing magnesium oxide, aluminum oxide and silicon dioxide according to a molar ratio of 1:1:3, respectively doping barium oxide, a barium oxide and yttrium oxide mixture or a zirconium oxide and yttrium oxide mixture, placing the mixture in a 1L nylon ball milling tank, adding absolute ethyl alcohol, and mixing for 24 hours by an omnibearing planet wheel ball mill at a rotating speed of 370 revolutions per minute to obtain slurry; wherein the magnesium oxide, the aluminum oxide and the silicon dioxide account for 75 percent of the total formula by mol, and the doped barium oxide accounts for 25 percent of the total formula by mol; the molar proportions of barium oxide and yttrium oxide in the total formula are respectively 20% and 5%; the molar proportions of the zirconium oxide and the yttrium oxide in the total formula are respectively 20% and 5%;

b. b, placing the slurry obtained in the step a in an electric heating blowing constant-temperature drying oven at the temperature of 65 ℃ for 24-36 hours, removing ethanol, manually grinding and crushing the dried blocks by using an agate mortar, sieving by using a 200-mesh sieve to obtain powder, and bottling;

c. b, pouring the powder obtained in the step b into an alumina crucible, smelting for 2 hours at 1600 ℃ at a heating speed of 10 ℃/min, and quickly taking out the high-temperature melt to be quenched in cold water to obtain mother-phase glass slag;

d. c, grinding and crushing the mother-phase glass slag obtained in the step c by using an agate mortar, and screening by using a 325-mesh stainless steel screen to obtain glass powder;

e. d, adding the glass powder obtained in the step d into a polyvinyl alcohol aqueous solution with the concentration of 10% according to the volume ratio of 3:1, stirring for 30 minutes by using a glass rod, standing for 1 hour after the glass powder is uniform, and packaging after no bubbles exist to obtain a paste;

f. and e, coating the paste obtained in the step e on the surface of the sensitive ceramic bead body, uniformly distributing and forming the paste on the surface of the bead body by utilizing the surface tension of the sensitive ceramic bead body, and sintering the bead body for 20 minutes at the temperature of 900 ℃ to form the compact glass ceramic material (1).

2. A preparation method of a glass ceramic material for packaging a high-temperature-resistant vacuum thermistor is characterized in that magnesium oxide, aluminum oxide and silicon dioxide are used as mother phase glass forming materials, barium oxide, a barium oxide and yttrium oxide mixture or a zirconium oxide and yttrium oxide mixture is doped respectively, and the specific operation is carried out according to the following steps:

a. weighing magnesium oxide, aluminum oxide and silicon dioxide according to a molar ratio of 1:1:3, respectively doping a barium oxide, barium oxide and yttrium oxide mixture or a zirconium oxide and yttrium oxide mixture, placing the mixture in a 1L nylon ball milling tank, adding ethanol, and mixing for 24 hours by means of an omnibearing planet wheel ball mill at a rotating speed of 370 r/min to obtain slurry, wherein the magnesium oxide, the aluminum oxide and the silicon dioxide account for 75% of the total formula, and the doped barium oxide accounts for 25% of the total formula; the molar proportions of barium oxide and yttrium oxide in the total formula are respectively 20% and 5%;

b. b, placing the slurry obtained in the step a in an electric heating blowing constant-temperature drying oven at the temperature of 65 ℃ for 24-36 hours, removing ethanol, manually grinding and crushing the dried blocks by using an agate mortar, sieving by using a 200-mesh sieve to obtain powder, and bottling;

c. pouring the powder obtained in the step b into an alumina crucible, heating at a speed of 10 ℃/min, smelting at a temperature of 1600 ℃ for 2 hours, quickly taking out the high-temperature melt, and quenching in cold water to obtain mother-phase glass slag;

d. c, grinding and crushing the mother-phase glass slag obtained in the step c by using an agate mortar, and screening by using a 325-mesh stainless steel screen to obtain a glass powder material;

e. d, adding the glass powder obtained in the step d into a polyvinyl alcohol aqueous solution with the concentration of 10% according to the volume ratio of 3:1, stirring for 30 minutes by using a glass rod, standing for 1 hour after the glass powder is uniform, and packaging after no bubbles exist to obtain a paste;

f. and e, coating the paste obtained in the step e on the surface of the sensitive ceramic bead body, uniformly distributing and forming the paste on the surface of the bead body by utilizing the surface tension of the sensitive ceramic bead body, and sintering the bead body for 20 minutes at the temperature of 900 ℃ to form the compact glass ceramic material (1).

Technical Field

The invention belongs to the technical field of electronic component packaging, and particularly relates to a glass ceramic material for packaging a high-temperature-resistant vacuum thermistor and a preparation method thereof.

Background

The high temperature resistant vacuum thermistor required in the domestic aerospace field has been exclusively supplied by Xinjiang physicochemical technical research institute of Chinese academy of sciences. With the rapid development of the aerospace field in recent years, the performance requirements of aerospace users on high-temperature-resistant vacuum thermistor products are gradually improved. The aerospace user requires the high-temperature-resistant vacuum thermistor to be stably in service under the temperature condition of 900 ℃ in vacuum and can resist 1000 times of high-temperature and low-temperature impact in the first three five periods. The analysis result of the reliability blinding test of the thermistor at the temperature of 900 ℃ in vacuum shows that the high-temperature performance of the packaging material and whether the sealing structure of the thermistor can keep high consistency when the thermistor is subjected to thermal shock are key factors influencing the service life of the device besides the self performance of the internal sensitive element and the reliability of the metal lead. At present, a high-temperature-resistant vacuum thermistor is packaged by adopting a cement (outer) -glass (inner) composite structure. Although the structure improves the overall high-temperature tolerance of the thermistor, the external cement is easy to generate higher residual stress in the packaging and forming process to cause the cracking of a cement layer, and simultaneously, the curve goodness of fit of the thermal expansion coefficients between the external cement and the inner layer glass and between the packaging structure and the NTC ceramic and the metal lead wire along with the temperature change is not good, so that the high-low temperature impact resistance of the thermistor can not meet the new technical index requirements, in addition, when the inner layer low-temperature glass is circulated at the temperature of 100-900 ℃, the continuous solidification shrinkage generates repeated acting force on the platinum metal lead wire, the platinum wire is broken and fails, and the service life of elements is influenced.

The glass ceramic is a composite structure material which is obtained by controlling glass crystallization and consists of amorphous phase glass and crystalline phase ceramic, has the performance advantages of the amorphous glass and the ceramic, has wider thermal expansion coefficient adjusting range, higher thermal stability and thermal shock resistance, and is a packaging material with great development potential. The applications of the glass ceramic packaging materials at present can be mainly summarized into two main types: one kind of the lead-containing glass can be used as a substitute for lead-containing glass to meet the requirements of medium and low temperature application; the other type is used as a packaging material of the solid oxide fuel cell (the temperature is less than or equal to 700 ℃). The latter shows the potential of high temperature application of glass ceramic packaging materials, but is not yet applied to the packaging of high temperature resistant thermistors. Therefore, the invention provides a glass ceramic material suitable for packaging a high-temperature-resistant vacuum thermistor product, breaks through the packaging material and the technical bottleneck of the high-temperature-resistant thermistor, and has important practical significance for meeting the continuously improved requirement indexes of aerospace users and developing the high-temperature-resistant vacuum thermistor with international advanced level.

Disclosure of Invention

The invention aims to solve the problems of cracking failure caused by mismatch of thermal expansion coefficients and platinum wire lead breakage failure caused by repeated solidification and shrinkage of inner-layer low-melting-point glass in the existing multilayer composite packaging structure, and provides a glass ceramic material for packaging a high-temperature-resistant vacuum thermistor and a preparation method thereof. Meanwhile, by utilizing a forming mechanism of the glass ceramic, the glass ceramic can be formed by sintering at the temperature of 900 ℃ and meanwhile can be packaged and formed, the packaging process is simplified, the packaging quality and the product consistency are improved, and the method has important practical significance for completing new requirement indexes of aerospace users and developing high-temperature-resistant vacuum thermistors of international advanced level.

The invention relates to a glass ceramic material for packaging a high-temperature-resistant vacuum thermistor, which takes magnesium oxide, aluminum oxide and silicon dioxide as mother phase glass forming materials, and respectively dopes barium oxide, a barium oxide and yttrium oxide mixture or a zirconium oxide and yttrium oxide mixture, and the specific operation is carried out according to the following steps:

a. weighing magnesium oxide, aluminum oxide and silicon dioxide according to a molar ratio of 1:1:3, respectively doping barium oxide, a barium oxide and yttrium oxide mixture or a zirconium oxide and yttrium oxide mixture, placing the mixture in a 1L nylon ball milling tank, adding absolute ethyl alcohol, and mixing for 24 hours by an omnibearing planet wheel ball mill at a rotating speed of 370 revolutions per minute to obtain slurry; wherein the magnesium oxide, the aluminum oxide and the silicon dioxide account for 75 percent of the total formula by mol, and the doped barium oxide accounts for 25 percent of the total formula by mol; the molar proportions of barium oxide and yttrium oxide in the total formula are respectively 20% and 5%; the molar proportions of the zirconium oxide and the yttrium oxide in the total formula are respectively 20% and 5%;

b. b, placing the slurry obtained in the step a in an electric heating blowing constant-temperature drying oven at the temperature of 65 ℃ for 24-36 hours, removing ethanol, manually grinding and crushing the dried blocks by using an agate mortar, sieving by using a 200-mesh sieve to obtain powder, and bottling;

c. b, pouring the powder obtained in the step b into an alumina crucible, smelting for 2 hours at 1600 ℃ at a heating speed of 10 ℃/min, and quickly taking out the high-temperature melt to be quenched in cold water to obtain mother-phase glass slag;

d. c, grinding and crushing the mother-phase glass slag obtained in the step c by using an agate mortar, and screening by using a 325-mesh stainless steel screen to obtain glass powder;

e. d, adding the glass powder obtained in the step d into a polyvinyl alcohol aqueous solution with the concentration of 10% according to the volume ratio of 3:1, stirring for 30 minutes by using a glass rod, standing for 1 hour after the glass powder is uniform, and packaging after no bubbles exist to obtain a paste;

f. and e, coating the paste obtained in the step e on the surface of the sensitive ceramic bead body, uniformly distributing and forming the paste on the surface of the bead body by utilizing the surface tension of the sensitive ceramic bead body, and sintering the bead body for 20 minutes at the temperature of 900 ℃ to form the compact glass ceramic material (1).

A preparation method of a glass ceramic material for packaging a high-temperature-resistant vacuum thermistor comprises the following steps of respectively doping barium oxide, a mixture of barium oxide and yttrium oxide or a mixture of zirconium oxide and yttrium oxide into a mother phase glass forming material comprising magnesium oxide, aluminum oxide and silicon dioxide:

a. weighing magnesium oxide, aluminum oxide and silicon dioxide according to a molar ratio of 1:1:3, respectively doping a barium oxide, barium oxide and yttrium oxide mixture or a zirconium oxide and yttrium oxide mixture, placing the mixture in a 1L nylon ball milling tank, adding ethanol, and mixing for 24 hours by means of an omnibearing planet wheel ball mill at a rotating speed of 370 r/min to obtain slurry, wherein the magnesium oxide, the aluminum oxide and the silicon dioxide account for 75% of the total formula, and the doped barium oxide accounts for 25% of the total formula; the molar proportions of barium oxide and yttrium oxide in the total formula are respectively 20% and 5%;

b. b, placing the slurry obtained in the step a in an electric heating blowing constant-temperature drying oven at the temperature of 65 ℃ for 24-36 hours, removing ethanol, manually grinding and crushing the dried blocks by using an agate mortar, sieving by using a 200-mesh sieve to obtain powder, and bottling;

c. pouring the powder obtained in the step b into an alumina crucible, heating at a speed of 10 ℃/min, smelting at a temperature of 1600 ℃ for 2 hours, quickly taking out the high-temperature melt, and quenching in cold water to obtain mother-phase glass slag;

d. c, grinding and crushing the mother-phase glass slag obtained in the step c by using an agate mortar, and screening by using a 325-mesh stainless steel screen to obtain glass powder;

e. d, adding the glass powder obtained in the step d into a polyvinyl alcohol aqueous solution with the concentration of 10% according to the volume ratio of 3:1, stirring for 30 minutes by using a glass rod, standing for 1 hour after the glass powder is uniform, and packaging after no bubbles exist to obtain a paste;

f. and e, coating the paste obtained in the step e on the surface of the sensitive ceramic bead body, uniformly distributing and forming the paste on the surface of the bead body by utilizing the surface tension of the sensitive ceramic bead body, and sintering the bead body for 20 minutes at the temperature of 900 ℃ to form the compact glass ceramic material (1).

The invention relates to a glass ceramic material for packaging a high-temperature-resistant vacuum thermistor and a preparation method thereof.

The glass ceramic material (1) obtained is used for packaging the periphery of Negative Temperature Coefficient (NTC) sensitive body ceramic (2) embedded with a platinum wire lead (3) to form a packaging structure.

The glass ceramic material for packaging the high-temperature-resistant vacuum thermistor and the preparation method thereof have the advantages that:

1. the mother phase glass is sintered at 900 ℃ to be converted into glass ceramic, and meanwhile, the packaging structure is formed, and the packaging process is greatly simplified through one-step packaging molding, so that the packaging quality and consistency of products are improved.

2. The glass ceramic material has better thermal stability at the temperature of 900 ℃, and solves the problem of breakage and failure of a platinum wire lead caused by repeated solidification and shrinkage of low-melting-point glass in the original packaging structure.

3. The packaged high-temperature-resistant vacuum thermistor can reach the technical index of 1000 times of high-low temperature impact at 100-900 ℃ under vacuum, and meanwhile, the change rate of the zero-power resistance value is less than 20 percent, namely the latest technical index requirement of aerospace users is met.

Drawings

FIG. 1 is a view showing a state of use of the present invention, in which 1-glass ceramic sealing material; 2-NTC sensitive body ceramic; 3-platinum wire lead.

Detailed Description

Example 1

Magnesium oxide, aluminum oxide and silicon dioxide are used as mother phase glass forming materials according to the molar ratio of 1:1:3, the molar ratio of the magnesium oxide, the aluminum oxide and the silicon dioxide accounts for 75 percent of the total formula, and barium oxide accounting for 25 percent of the total formula is doped; the specific operation is carried out according to the following steps:

a. 15MgO-15Al₂O₃-45SiO₂25BaO, namely weighing magnesium oxide, aluminum oxide, silicon dioxide and barium oxide powder with the purity of 99.99 percent respectively, putting the powder into a 1L nylon ball mill tank, adding absolute ethyl alcohol, mixing for 24 hours by means of an omnibearing planet wheel ball mill at the rotating speed of 370 revolutions per minute to obtain slurry, and adding no grinding ball in the mixing process;

b. b, drying the slurry obtained in the step a for 24 hours at a constant temperature of 65 ℃ by electric heating and air blasting, removing ethanol, manually grinding and crushing the dried blocks by using an agate mortar, sieving the crushed blocks by using a 200-mesh sieve to obtain powder, and bottling the powder;

c. b, pouring the powder obtained in the step b into an alumina crucible, smelting for 2 hours at 1600 ℃ at a heating speed of 10 ℃/min, and quickly taking out the high-temperature melt to be quenched in cold water to obtain mother-phase glass slag;

d. c, grinding and crushing the mother phase glass obtained in the step c by using an agate mortar, and screening by using a 325-mesh stainless steel screen to obtain glass powder;

e. d, adding a polyvinyl alcohol (PVA17-88) aqueous solution with the concentration of 10% into the glass powder obtained in the step d according to the volume ratio of 3:1, stirring for 30 minutes by using a glass rod, standing for 1 hour after the glass powder is uniform, and packaging after no bubbles exist to obtain a paste;

f. and e, coating the paste obtained in the step e on the surface of the sensitive ceramic bead body, uniformly distributing and forming the paste on the surface of the bead body by utilizing the surface tension of the sensitive ceramic bead body, and sintering the bead body for 20 minutes at the temperature of 900 ℃ to form the compact Mg-Al-Si-Ba-O glass ceramic material.

The Negative Temperature Coefficient (NTC) sensitive body ceramic 2 with embedded platinum wire lead 3 and the packaging structure formed by the obtained glass ceramic material 1 are superior to 5 multiplied by 10^-3Aging at 900 ℃ for 50h under a vacuum environment of Pa, and performing thermal shock test at 100-900 ℃ to show that: the high-temperature-resistant vacuum thermistor has good thermal stability at the temperature of 900 ℃, can resist 1000 times of high and low temperature impact in vacuum, and has the change rate of the resistance value of the zero-power resistor less than 18.77%.

Example 2

According to the molar ratio of 1:1:3, magnesium oxide, aluminum oxide and silicon dioxide are used as mother phase glass forming materials, the molar ratio of the mother phase glass forming materials accounts for 75 percent of the total formula, barium oxide and yttrium oxide mixtures which account for 20 percent and 5 percent of the total formula are doped, and the specific operation is carried out according to the following steps:

a. 15MgO-15Al₂O₃-45SiO₂-20BaO-5Y₂O₃Weighing magnesium oxide, aluminum oxide, silicon dioxide, barium oxide and yttrium oxide powder with the purity of 99.99 percent, putting the powder into a 1L nylon ball mill, adding ethanol, mixing for 24 hours by an omnibearing planet wheel ball mill at the rotating speed of 370 r/min to obtain slurry, and mixing the slurryGrinding balls are not added in the process;

b. b, drying the slurry obtained in the step a for 30 hours at a constant temperature by electric heating and air blowing at a temperature of 65 ℃, removing ethanol, manually grinding and crushing the dried blocks by using an agate mortar, sieving by using a 200-mesh sieve to obtain powder, and bottling;

c. b, pouring the powder obtained in the step b into an alumina crucible, smelting for 2 hours at 1600 ℃ at a heating speed of 10 ℃/min, and quickly taking out the high-temperature melt to be quenched in cold water to obtain mother-phase glass slag;

d. c, grinding and crushing the mother phase glass obtained in the step c by using an agate mortar, and screening by using a 325-mesh stainless steel screen to obtain glass powder;

e. d, adding a 10% polyvinyl alcohol (PVA17-88) aqueous solution into the powder obtained in the step d according to the volume ratio of 3:1, stirring for 30 minutes by using a glass rod, standing for 1 hour after the mixture is uniform, obtaining a paste after no bubbles exist, and packaging;

f. and e, coating the paste obtained in the step e on the surface of the sensitive ceramic bead body, uniformly distributing and forming the paste on the surface of the bead body by utilizing the surface tension of the sensitive ceramic bead body, and sintering the bead body for 20 minutes at the temperature of 900 ℃ to form the compact Mg-Al-Si-Ba-Y-O glass ceramic material.

The Negative Temperature Coefficient (NTC) sensitive body ceramic 2 with embedded platinum wire lead 3 and the packaging structure formed by the obtained glass ceramic material 1 are superior to 5 multiplied by 10^-3Aging at 900 ℃ for 50h under a vacuum environment of Pa, and performing thermal shock test at 100-900 ℃ to show that: the high-temperature-resistant vacuum thermistor has good thermal stability at the temperature of 900 ℃, can resist high and low temperature impact for 1000 times in vacuum, and has the change rate of the resistance value of the zero-power resistor of less than 8.18 percent.

Example 3

According to the molar ratio of 1:1:3, magnesium oxide, aluminum oxide and silicon dioxide are used as mother phase glass forming materials, the molar ratio of the mother phase glass forming materials accounts for 75 percent of the total formula, zirconium oxide and yttrium oxide mixtures which account for 20 percent and 5 percent of the total formula are doped, and the specific operation is carried out according to the following steps:

a. 15MgO-15Al₂O₃-45SiO₂-20ZrO₂-5Y₂O₃Weighing magnesium oxide, aluminum oxide, silicon dioxide, zirconium oxide and yttrium oxide with the purity of 99.99%, placing the materials into a 1L nylon ball mill, adding ethanol, mixing for 24 hours by means of an omnibearing planet wheel ball mill at the rotating speed of 370 r/min to obtain slurry, and adding no grinding ball in the mixing process;

b. b, drying the slurry obtained in the step a for 36 hours at a constant temperature of 65 ℃ by electric heating and air blasting, removing ethanol, manually grinding and crushing the dried blocks by using an agate mortar, sieving the crushed blocks by using a 200-mesh sieve to obtain powder, and bottling the powder;

c. b, pouring the powder mixture obtained in the step b into an alumina crucible, smelting for 2 hours at 1600 ℃ at a heating speed of 10 ℃/min, and quickly taking out the high-temperature melt to be quenched in cold water to obtain mother-phase glass slag;

d. c, grinding and crushing the mother phase glass obtained in the step c by using an agate mortar, and screening by using a 325-mesh stainless steel screen to obtain glass powder;

e. d, adding a 10% polyvinyl alcohol (PVA17-88) aqueous solution into the powder material obtained in the step d according to the volume ratio of 3:1, stirring for 30 minutes by using a glass rod, standing for 1 hour after the mixture is uniform, and packaging after no bubbles exist;

f. and e, coating the paste obtained in the step e on the surface of the sensitive ceramic bead body, uniformly distributing and forming the paste on the surface of the bead body by utilizing the surface tension of the sensitive ceramic bead body, and sintering the paste at the temperature of 900 ℃ for 20 minutes to form the compact Mg-Al-Si-Zr-Y-O glass ceramic material.

The Negative Temperature Coefficient (NTC) sensitive body ceramic 2 with embedded platinum wire lead 3 and the packaging structure formed by the obtained glass ceramic material 1 are superior to 5 multiplied by 10^-3Aging at 900 ℃ for 50h under a vacuum environment of Pa, and performing thermal shock test at 100-900 ℃ to show that: the high-temperature-resistant vacuum thermistor has good thermal stability at the temperature of 900 ℃, can resist 1000 times of high and low temperature impact in vacuum, and has the change rate of the zero-power resistance value of less than 20%.