High-temperature-resistant platinum slurry and preparation method thereof
By using 85-95% platinum powder, 0-3% lead-free glass powder and 5-20% organic carrier platinum slurry, the problem that traditional technology is difficult to maintain the performance of sensors and optical components in high temperature environments is solved, and a platinum layer with high bond strength and long life is achieved on complex structures, which is suitable for high temperature environments of 1000℃ to 1200℃.
Patent Information
- Application Number
- CN202411763075.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-03
- Publication Date
- 2025-04-15
AI Technical Summary
The prior art is difficult to maintain the performance and accuracy of sensors and optical components in high temperature environments, especially under conditions above 1000°C, and traditional coating processes are difficult to form a uniform, high bonding strength high-temperature anti-heat film layer on complex structures.
A platinum slurry with a fineness of ≤10μm is prepared by a spherical micron platinum powder of 85 to 95%, 0 to 3% lead-free glass powder and 5 to 20% organic carrier by multiple rolling and defoaming treatments, and a platinum layer with high bonding strength is formed on the device by spraying or brushing.
Under a high temperature environment of 1000°C to 1200°C, the platinum layer can maintain long-term stability and repeated measurement properties, forming a uniform and smooth platinum layer with high adhesion and long service life. It is suitable for complex structural devices, reducing maintenance costs and extending the service life of the equipment.
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Figure CN119819919A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of electronic paste preparation, and in particular to a high temperature resistant platinum paste for sensor devices and a preparation method thereof. Technical Background
[0002] In the fields of aviation, aerospace, metrology, etc., there is an urgent need for sensors, optical components and other devices to be able to operate stably in extremely high temperature environments. In high temperature environments, the oxidation resistance, optical properties and service life of sensors, optical components and other devices will be significantly affected. In order to ensure the performance of the device, a layer of excellent performance film is prepared on the surface of the device to achieve the purpose of changing its high temperature resistance, optical properties and life.
[0003] The film materials on the surface of the device include various metal or non-metal materials such as platinum, gold, silver, copper, chromium, aluminum, fluoride, etc. The selection of these materials depends on the specific application requirements. According to the specific application requirements, single-layer or multi-layer film layers can also be selected to achieve special effects. General film materials do not have the characteristics of high temperature resistance and oxidation resistance and cannot serve above 1000°C. In addition, in practical applications, some devices have complex structures, such as inner curved surface structures, which makes it difficult to perform coating processes on the inner curved surfaces. Traditional electroplating, chemical plating, sputtering and other methods cannot form a uniform, smooth, high-bonding strength and long-life high-temperature resistant film layer on such structures.
[0004] The performance and accuracy of sensors, optical elements and other devices in the existing technology are limited when faced with high temperature environments exceeding 1000°C, which restricts their application in aviation, aerospace, metrology and other fields. Summary of the invention
[0005] In view of the shortcomings of the prior art, the present invention provides a high temperature resistant platinum slurry and a preparation method thereof. The platinum slurry can be used stably for a long time at 1000°C to 1200°C, and can form a high temperature resistant platinum layer with high bonding strength on a device with a complex structure, and the platinum layer can maintain long-term stability and repeatability in a high temperature environment.
[0006] To solve the above problems, the technical solution adopted by the present invention is as follows:
[0007] A high temperature resistant platinum slurry comprises platinum powder, lead-free glass powder and an organic carrier. The components thereof are calculated by mass percentage as follows: 85-95% of platinum powder, 0-3% of lead-free glass powder and 5-20% of the organic carrier.
[0008] The platinum powder is a spherical micron platinum powder with an average particle size of 1.1 to 1.4 μm and a tap density of 9.3 to 10.7 g / cm 3 .
[0009] The lead-free glass powder is of SiO2-CaO-B2O3 system, with an average particle size of ≤2μm, and its components are as follows by mass percentage: 20% to 45% CaO, 5% to 30% B2O3, 1% to 15% Al2O3, 0% to 8% MgO, and the balance is SiO2.
[0010] The components of the organic carrier are calculated by mass percentage as follows: 1% to 20% of a thickener, 0% to 10% of a surfactant, and the balance is an organic solvent.
[0011] The organic solvent is one or more of diethylene glycol butyl ether, butyl carbitol acetate, terpineol, and tributyl citrate.
[0012] The thickener is one or more of ethyl cellulose, methyl cellulose and nitro cellulose.
[0013] The surfactant is one or more of Span 85, lecithin, toluene and ethanol.
[0014] The method for preparing the platinum slurry comprises the following steps:
[0015] 1) Preparation of organic carrier
[0016] Take an organic solvent, a thickener, and a surfactant according to the ratio of claim 4, keep warm at 90° C. and stir until the thickener is completely dissolved, and cool at room temperature to form a uniform organic carrier without precipitation;
[0017] 2) Preparation of lead-free glass powder
[0018] Take lead-free raw materials according to the ratio of claim 3, ball mill, wet grind and mix, dry, melt the uniformly mixed lead-free raw materials at 1300° C., keep warm for 2 hours, obtain glass liquid after melting, quench the glass liquid with water to obtain bulk glass slag, ball mill the glass slag, dry, and pass through a 300-mesh sieve to obtain lead-free glass powder with an average particle size of ≤2 μm;
[0019] 3) Preparation of platinum slurry
[0020] Take platinum powder according to the ratio of claim 1, take the organic carrier and lead-free glass powder prepared in steps 2) and 3), preliminarily mix them, and then roll and degasse them for multiple times to obtain a high-temperature resistant platinum slurry for devices, the fineness of which is ≤10μm.
[0021] The specific rolling method of step 3) is to use a precision ceramic three-roller mill to repeatedly roll 3 to 5 times.
[0022] Step 3) The degassing method is to first use ultrasound to treat the slurry for 3 to 5 minutes, and finally use a vacuum degassing mixer to degas for 3 to 5 minutes.
[0023] The beneficial effects of the present invention are:
[0024] The present invention adopts an organic carrier prepared by ethyl cellulose, pineol, Sban 85 or ethyl cellulose, pineol, diethylene glycol butyl ether, and Sban 85. The carrier has good wettability with platinum powder and lead-free glass powder, and can meet the demand for slurry with a high solid content of ≥ 90%. By regulating the composition of the organic carrier, the obtained slurry system exhibits excellent rheological properties and thixotropic properties, ensuring its process adaptability in different applications, and can be used for different processes such as spraying, brushing, and screen printing.
[0025] The platinum slurry prepared by the invention can form a uniform, smooth and high-bonding-strength platinum layer on a device with an inner curved surface structure, and the preparation process is simple, the cost is low and the platinum slurry is suitable for large-scale production.
[0026] The platinum slurry prepared by the method of the present invention can form a uniform, smooth, high-bonding-strength and long-life platinum layer on a device with an inner curved surface structure through a spraying or brushing process. The platinum layer can work continuously for more than 8 weeks at 1000°C to 1200°C without falling off, has excellent high temperature resistance and stability, can work repeatedly, reduces maintenance costs and extends the service life of the equipment. The present invention not only improves the application range of platinum materials under extreme temperature conditions, but also ensures its good bonding performance on complex structure devices, providing a material selection and technical support for the development of high-performance device film preparation technology.
[0027] The platinum slurry of the present invention is used as a key material for functional devices, sensors, etc., and has potential application value in other applications in extreme high temperature environments due to its unique formula and preparation process. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Figure 1 This is an electron microscope image of the spherical micron platinum powder of the platinum slurry described in the present invention.
[0029] Figure 2 This is an optical photograph of the platinum coating prepared in the present invention. DETAILED DESCRIPTION
[0030] In order to better demonstrate the technical solutions, objectives and advantages of the present invention, the present invention will be described in more detail below in conjunction with specific embodiments, but the contents of the present invention are not limited thereby.
[0031] Example 1
[0032] The high temperature resistant platinum paste for devices is composed of spherical platinum powder, lead-free glass powder and organic carrier, and the components thereof are calculated by mass percentage as follows: 89% of spherical platinum powder, 1% of lead-free glass powder and 10% of organic carrier.
[0033] Specific preparation method:
[0034] 1. Preparation of organic carrier: Weigh 0.4 g of ethyl cellulose, 17.6 g of terpineol, and 2 g of Span 85 into a beaker, place the beaker in a constant temperature water bath at 90°C and stir until the additives are completely dissolved, and cool at room temperature to form a uniform organic carrier without precipitation.
[0035] 2. Preparation of lead-free glass powder: Weigh 9.6g of SiO2, 8.4g of B2O3, 7.5g of CaO, 3g of Al2O3, and 1.5g of MgO, and place each raw material in a ball mill for mixing and drying. Put the evenly mixed lead-free raw materials into an alumina crucible and melt them in a high-temperature furnace at 1300°C and keep them warm for 2h. After melting, glass liquid is obtained. The glass liquid is quenched with water to obtain bulk glass slag. The glass slag is then ball-milled, dried, and passed through a 300-mesh sieve to obtain lead-free glass powder with an average particle size of 1.82μm for later use.
[0036] 3. Preparation of platinum slurry: Weigh 26.7 g of spherical platinum powder, the platinum powder is spherical micron platinum powder, the average particle size is 1.1-1.4 μm, and the tap density is 9.3-10.7 g / cm 3 (See Figure 1 ), 0.3 g of lead-free glass powder and 3 g of an organic carrier were placed in a mortar for preliminary mixing, then rolled 5 times using a ceramic three-roll mill, and finally degassed to obtain a high-temperature resistant platinum slurry for devices with a fineness of ≤10 μm.
[0037] Device film preparation: The prepared platinum slurry was brushed on the inner surface of the device, left to level, then dried at 150°C for 10 min, and finally sintered at 1100°C for 10 min to obtain a platinum layer with a thickness of 11.6 μm, a roughness of Ra = 0.25 μm, and an adhesion of 45.N / mm 2 The coating is as Figure 2 described.
[0038] Example 2
[0039] The high temperature resistant platinum paste for devices is composed of spherical platinum powder and organic carrier, and the components thereof are calculated by mass percentage: 90% of spherical platinum powder and 10% of organic carrier.
[0040] Specific preparation method:
[0041] 1. Preparation of organic carrier: Weigh 0.4 g of ethyl cellulose, 13.6 g of pinene alcohol, 4 g of diethylene glycol butyl ether, and 2 g of Span 85 into a beaker, place the beaker in a constant temperature water bath at 90°C and stir until the additives are completely dissolved, and cool at room temperature to form a uniform organic carrier without precipitation.
[0042] 2. Preparation of platinum slurry: Weigh 27 g of spherical platinum powder, the platinum powder is spherical micron platinum powder, the average particle size is 1.1-1.4 μm, and the tap density is 9.3-10.7 g / cm 3 (See Figure 1 ), 3 g of the organic carrier was placed in a mortar for preliminary mixing, then rolled 5 times using a ceramic three-roll mill, and finally degassed to obtain a high-temperature resistant platinum slurry for devices with a fineness of ≤10 μm.
[0043] Device film preparation: The prepared platinum slurry was brushed on the inner surface of the device, left to level, then dried at 150°C for 10 min, and finally sintered at 1100°C for 10 min to obtain a platinum layer with a thickness of 10.3 μm, a roughness of Ra = 0.23 μm, and an adhesion of 41.3 N / mm 2 The coating is as Figure 2 described.
Claims
1. A high temperature resistant platinum slurry, characterized in that: The slurry comprises platinum powder, lead-free glass powder and organic carrier; the components thereof are calculated by mass percentage as follows: 85-95% of platinum powder, 0-3% of lead-free glass powder and 5-20% of organic carrier.
2. According to claim 1, it is characterized in that: The platinum powder is a spherical micron platinum powder with an average particle size of 1.1 to 1.4 μm and a tap density of 9.3 to 10.7 g / cm 3 .
3. According to claim 1, it is characterized in that: The lead-free glass powder is of SiO2-CaO-B2O3 system, with an average particle size of ≤2μm, and its components are as follows by mass percentage: 20% to 45% CaO, 5% to 30% B2O 3， 1% to 15% Al2O3, 0% to 8% MgO, and the balance is SiO2.
4. According to claim 1, it is characterized in that: The components of the organic carrier are calculated by mass percentage as follows: 1% to 20% of a thickener, 0% to 10% of a surfactant, and the balance is an organic solvent.
5. According to claim 4, it is characterized in that: The organic solvent is one or more of diethylene glycol butyl ether, butyl carbitol acetate, terpineol, and tributyl citrate.
6. According to claim 4, it is characterized in that: The thickener is one or more of ethyl cellulose, methyl cellulose and nitro cellulose.
7. According to claim 4, it is characterized in that: The surfactant is one or more of Span 85, lecithin, toluene and ethanol.
8. The method for preparing the platinum slurry according to any one of claims 1 to 7, characterized in that: The following steps are involved: 1) Preparation of organic carrier Take an organic solvent, a thickener, and a surfactant according to the ratio of claim 4, keep warm at 90° C. and stir until the thickener is completely dissolved, and cool at room temperature to form a uniform organic carrier without precipitation; 2) Preparation of lead-free glass powder Take lead-free raw materials according to the ratio of claim 3, ball mill, wet grind and mix, dry, melt the uniformly mixed lead-free raw materials at 1300° C., keep warm for 2 hours, obtain glass liquid after melting, quench the glass liquid with water to obtain bulk glass slag, ball mill the glass slag, dry, and pass through a 300-mesh sieve to obtain lead-free glass powder with an average particle size of ≤2 μm; 3) Preparation of platinum slurry Take platinum powder according to the ratio of claim 1, take the organic carrier and lead-free glass powder prepared in steps 2) and 3), preliminarily mix them, and then roll and degasse them for multiple times to obtain a high-temperature resistant platinum slurry for devices, the fineness of which is ≤10μm.
9. The preparation method according to claim 8, characterized in that: The specific rolling method of step 3) is to use a precision ceramic three-roller mill to repeatedly roll 3 to 5 times.
10. The preparation method according to claim 8, characterized in that: Step 3) The degassing method is to first use ultrasound to treat the slurry for 3 to 5 minutes, and finally use a vacuum degassing mixer to degas for 3 to 5 minutes.