CN102702808B - Infrared radiation coating capable of forming coating with low conductivity factor - Google Patents

Abstract

The invention discloses infrared radiation coating capable of forming coating with low heat conductivity factors. The infrared radiation coating is prepared by the following raw materials by weight percentage: 30-50% of spinel-silicate multiphase composite system infrared radiation powder materials, 3-15% of pore-creating agents, 0-20% of hexa-potassium titanate, 25-50% of sodium silicate, 5-15% of water, 1-10% of inorganic combination auxiliary, 0-2% of anti-settling agents, 0-3% of dispersing agents, 0-1% of defoaming agents and 0-1% of flatting agents. After the coating is dried and cured, the coatings of porous structures are formed in the using process, have excellent infrared radiation performance and low conductivity factors, can be firmly combined with a fireproof material base body, do not crack when used for a long time under the high temperature of 500-1300 DEG C, do not fall off, and are corrosion resisting and excellent in thermal shock resistance.

Description

Infrared Radiating Coatings Capable of Forming Coatings with Low Thermal Conductivity

technical field

The invention relates to the field of infrared radiation energy-saving materials, in particular to an infrared radiation coating capable of forming a low thermal conductivity coating.

Background technique

The application of infrared radiation energy-saving technology is an effective way to improve the energy utilization efficiency of industrial furnaces. The application of infrared radiation coatings on the inner wall surface of refractory materials in industrial kilns can effectively improve the infrared radiation ability and spectral characteristics of the surface of objects participating in radiation heat transfer in the furnace, enhance the radiation heat transfer efficiency in the furnace, promote the heating process, and improve The uniformity of the temperature inside the kiln can speed up the heating speed and quality of the workpiece, shorten the production cycle, improve the effectiveness of energy utilization in the process of using the industrial kiln, and reduce harmful gas emissions, reduce the temperature of the exhaust gas, and prolong the life of the industrial kiln. Good comprehensive benefits such as furnace service life.

In recent years, my country's infrared radiation coating has been greatly developed, and its energy-saving effect in industrial kilns has been paid more and more attention. Compared with kiln lining materials, my country's infrared radiation coatings often have higher thermal conductivity, which will increase the heat conduction from the inner wall of the kiln to the outer wall of the kiln, increase the heat dissipation of the kiln, and reduce the heat dissipation of the kiln. Effectiveness of energy use. Existing low thermal conductivity materials often have poor infrared radiation performance or poor high temperature stability. Reducing the thermal conductivity of the coating through the composition design and structure control of the infrared radiation coating is an effective way to improve the use effect of the infrared radiation coating and fully improve the energy utilization efficiency of the kiln. Wide application is of great significance.

Contents of the invention

The technical problem to be solved by the present invention is to provide an infrared radiation coating capable of forming a low thermal conductivity coating in view of the above-mentioned prior art, so as to improve the use effect of the infrared radiation coating.

The technical solution adopted by the present invention to solve the above-mentioned technical problems is: an infrared radiation coating capable of forming a coating with low thermal conductivity , which is prepared by mixing the following components, and the components and their contents are determined by mass The percentage is calculated as: spinel-silicate multiphase composite system infrared radiation powder: 30~50%, pore forming agent: 3~15%, potassium hexatitanate: 0~20%, water glass: 25~50% %, water: 5~15%, inorganic bonding agent: 1~10%, anti-settling agent: 0~2%, dispersant: 0~3%, defoamer: 0~1%, leveling agent: 0 ~1%.

According to the above scheme, the preparation method of the infrared radiation powder of the spinel-silicate multiphase composite system includes the following steps: 1) batching various raw materials according to the specified ratio, and then ball milling the batching, The preliminary treatment of mixing, drying and pressing to form a block body; the raw materials include A component forming spinel solid solution, B component forming silicate mineral and accelerator C component, the mass of which is The ratio is 100%: 20~300%: 0~15%, wherein, the A component includes Fe ₂ O ₃ , MnO ₂ , CuO, Co ₂ O ₃ , Mo ₂ O ₃ , NiO, V ₂ O ₅ and WO ₃ , the B component includes Al ₂ O ₃ , SiO ₂ , MgO, BaO, CaO and TiO ₂ , the accelerator C component includes glass powder and B ₂ O ₃ , each group The content is calculated by mass percentage: Fe ₂ O ₃ : 0~60%, MnO ₂ : 0~60%, Al ₂ O ₃ : 5~50%, SiO ₂ : 5~50%, CuO: 0~12% , Co ₂ O ₃ : 0~10%, MgO: 0~10%, Mo ₂ O ₃ : 0~6%, NiO: 0~6%, TiO ₂ : 0~6%, V ₂ O ₅ : 0~ 5%, WO ₃ : 0~5%, BaO: 0~3%, CaO: 0~3%, glass powder: 0~3%, B ₂ O ₃ : 0~3%; The block body is heated and kept in the temperature range of 800~980°C for 1~6 hours to form a spinel solid solution; then continue to heat up to the temperature range of 1100~1300°C for 2~ After 8 hours, silicate minerals are formed, and the spinel-type solid solution and silicate minerals are multi-phase composited to form a black sintered body with a multi-phase composite structure; 3) The black sintered body obtained in step 2) is crushed, pulverized and Pass through 200-500 sieves to obtain spinel-silicate multi-phase composite system infrared radiation powder.

According to the above scheme, the inorganic bonding aid is prepared by mixing the following components: Al ₂ O ₃ : 20~40%, SiO ₂ : 20~60%, MgO: 2~10%, TiO ₂ : 2 ~10%, NiO: 0~10%, Cr ₂ O ₃ : 0~10%, B ₂ O ₅ : 0~10%, the above are all in terms of mass percentage.

According to the above scheme, the pore-forming agent is composed of graphite and starch, and the mass ratio of graphite and starch is 50%:50%.

According to the scheme above, the anti-settling agent is organic bentonite; the dispersant is sodium phosphate; the defoamer is tributyl phosphate; and the leveling agent is water-based acrylic resin.

In the present invention, when mixing and preparing, the above-mentioned components are weighed according to the proportion, stirred and mixed for 1 to 6 hours, and the viscous suspension fluid infrared radiation coating is obtained.

The reaction mechanism of the infrared radiation coating of the present invention is: form silica sol and inorganic bonding aid after drying and solidifying by water glass, form liquid phase at high temperature to increase the binding force of infrared radiation coating, and the pore-forming agent in the process of heating and using The porous structure formed in the coating reduces the thermal conductivity of the coating, and the addition of potassium hexatitanate with low thermal conductivity further reduces the thermal conductivity of the coating.

When used on a refractory material substrate, the infrared radiation coating of the present invention is directly sprayed on the surface of the substrate, and the infrared radiation coating is formed after drying and curing. Excellent thermal shock performance.

Compared with the prior art, the infrared radiation coating of the present invention has the following characteristics:

1) Add a pore-forming agent to the coating to make the coating form a porous structure during heating, reduce the thermal conductivity of the coating, and enhance the thermal insulation effect of the coating. At the same time, potassium hexatitanate with low thermal conductivity is added to further reduce The thermal conductivity of the coating and the improvement of the thermal insulation effect of the coating;

2) Inorganic bonding additives are added to the coating. During the heating process, the additives form a high-temperature liquid phase in the coating, which acts to close the pores and form a separated closed-cell structure, which is beneficial to reduce the thermal conductivity and can promote The combination of the coating and the substrate prevents the coating structure from cracking or falling off, and improves the thermal shock resistance of the coating;

3) The pre-prepared spinel-silicate multiphase composite system powder is used as the infrared radiation material in the coating. The composite system powder has excellent infrared radiation performance, so that the porous structure coating maintains high infrared radiation Performance, to ensure the energy-saving effect of the coating.

The coating formed by the infrared radiation coating of the present invention has both excellent infrared radiation performance and low thermal conductivity, and can be firmly combined with the refractory material matrix. It has excellent structure and performance at high temperatures, corrosion resistance, and thermal shock resistance. It can be used Used on the surface of the lining materials of industrial kilns in building materials, metallurgy, thermal power, petrochemical, chemical, light industry and other industries to improve the energy utilization efficiency of industrial kilns, protect the lining materials of kilns, and prolong the service life of kiln lining materials .

Description of drawings

Fig. 1 is the XRD spectrum of embodiment 1 through 1200 ℃ heat treatment infrared radiation coating;

Fig. 2 is the SEM photo of the infrared radiation coating in Example 1 after heat treatment at 1200°C.

Detailed ways

The present invention will be further described below in conjunction with the examples, but this description will not constitute a limitation to the present invention.

Example 1

In terms of mass percentage, it is 40% of spinel-silicate multiphase composite system infrared radiation powder, 5% of pore-forming agent, 10% of potassium hexatitanate, 30% of water glass, 5% of water, and 6.7% of inorganic bonding agent , organic bentonite 1%, sodium phosphate 2%, tributyl phosphate 0.2%, water-based acrylic resin 0.1%, the pore-forming agent is composed of graphite and starch, and the mass ratio of graphite and starch is 50%: 50% , Weigh the above-mentioned components, stir and mix for 4 hours, and then obtain the infrared radiation coating of viscous suspending fluid.

Among them, the infrared radiation powder of the spinel-silicate multi-phase composite system includes the A component forming the spinel solid solution, the B component forming the silicate mineral and the accelerator C component, wherein the The A component includes Fe ₂ O ₃ , MnO ₂ , CuO and Mo ₂ O ₃ , the B component includes Al ₂ O ₃ , SiO ₂ , MgO and TiO ₂ , and the accelerator C group The component includes B ₂ O ₃ , and the content of each component is calculated by mass percentage: 10% Fe ₂ O ₃ , 16% MnO ₂ , 8% CuO, 1% Mo ₂ O ₃ , 50% Al ₂ O ₃ , 12% SiO ₂ , 1.5% MgO, 0.5% TiO ₂ and 1% BaO; the preparation process is as follows: mix various raw materials according to the specified proportion, ball mill, mix, dry and press the ingredients into a block body; In the process of sintering and preparing the green body, it is first heated to 950°C for 2 hours to form a spinel-type solid solution, and then continue to heat up to 1200°C for 8 hours to make the spinel-type solid solution and silicate minerals undergo multiphase Composite to form a black sintered body with a multi-phase composite structure; after crushing, crushing and passing through a 200-mesh sieve, the infrared radiation powder of the spinel-silicate multi-phase composite system is prepared;

Among them, the mass ratio of each component in the inorganic bonding agent is: 20% Al ₂ O ₃ , 60% SiO ₂ , 5% MgO, 2% TiO ₂ , 5% NiO, 5% Cr ₂ O ₃ and 3% B ₂ O ₅ , prepared by mixing.

After the surface of the refractory substrate is purged, the above-mentioned infrared radiation coating is sprayed on the surface, and the infrared radiation coating is formed after drying and curing. The normal full-band emissivity of the infrared radiation coating is 0.92, the emissivity of the 8μm~25μm band is 0.91, the emissivity of the 8μm~14μm band is 0.93, and the emissivity of the 14μm~25μm band is 0.93. The thermal conductivity of the infrared radiation coating at 1000°C is 0.26W/(m·K). The infrared radiation coating is subjected to air natural cooling thermal shock cycle in the range of normal temperature to 1200 ℃, and the coating surface has no cracks and the coating does not fall off after 30 cycles.

The XRD spectrum of Fig. 1 shows that the infrared radiation coating mainly contains transition metal oxide spinel type solid solution and mullite, in addition, also contains a small amount of magnesium aluminum spinel, and the infrared radiation ceramic component in the coating has a good high temperature stability. Figure 1 shows that the infrared radiation ceramic coating has a uniform porous structure after heat treatment, which is conducive to reducing the thermal conductivity of the coating.

Example 2

According to the mass ratio, 30% spinel-silicate multiphase composite system infrared radiation powder, 3% pore forming agent, 20% potassium hexatitanate, 25% water glass, 10% water, 8% inorganic bonding agent , 2% organic bentonite, 1% sodium phosphate, 0.5% tributyl phosphate, 0.5% water-based acrylic resin, the above-mentioned various components are weighed according to the proportion, and the described pore-forming agent is composed of graphite and starch. The mass ratio of starch and starch is 50%:50%. Stir and mix for 1 hour to obtain a viscous suspension fluid infrared radiation coating.

Among them, the mass ratio of each component in the infrared radiation powder of the spinel-silicate multiphase composite system is: 28%MnO ₂ , 12%CuO, 6%Mo ₂ O ₃ , 5%V ₂ O ₅ , 5% %WO ₃ , 5%Al ₂ O ₃ , 20%SiO ₂ , 10%MgO, 6%TiO ₂ and 3%CaO; the preparation process is: mix various raw materials according to the specified proportion, ball mill and mix the ingredients , dried and pressed into a block green body; in the firing preparation process of the block green body, it is first heated to 950 ° C for 4 hours to form a spinel solid solution, and then continue to heat up to 1300 ° C for 2 hours to make The spinel-type solid solution and silicate minerals are multi-phase compounded to form a black sintered body with a multi-phase compound structure; after crushing, crushing and passing through a 250 mesh sieve, the infrared radiation powder of the spinel-silicate multi-phase compound system is prepared material;

The mass ratio of each component in the inorganic bonding aid is: 40% Al ₂ O ₃ , 36% SiO ₂ , 2% MgO, 6% TiO ₂ , 6% NiO and 10% Cr ₂ O ₃ , prepared by mixing .

After the surface of the refractory substrate is purged, the above-mentioned infrared radiation coating is sprayed on the surface, and the infrared radiation coating is formed after drying and curing. The normal full band emissivity of the infrared radiation coating is 0.89, the emissivity of the 8 μm~25 μm band is 0.91, the emissivity of the 8 μm~14 μm band is 0.92, and the emissivity of the 14 μm~25 μm band is 0.93. The thermal conductivity of the infrared radiation coating at 1000°C is 0.31W/(m·K). The infrared radiation coating is subjected to air natural cooling thermal shock cycle in the range of normal temperature to 1200 ℃, and the coating surface has no cracks and the coating does not fall off after 30 cycles.

Example 3

According to the mass ratio, it is 50% spinel-silicate multiphase composite system infrared radiation powder, 3% pore forming agent, 33% water glass, 10% water, 1% inorganic bonding agent, 1% organic bentonite, 1% % tributyl phosphate, 1% water-based acrylic resin, the above-mentioned various components are weighed according to the proportion, stirred and mixed for 3 hours, and the infrared radiation coating of viscous suspension fluid is obtained.

Among them, the mass ratio of each component in the infrared radiation powder of the spinel-silicate multiphase composite system is: 10% Fe ₂ O ₃ , 60% MnO ₂ , 3% CuO, 4% Co ₂ O ₃ , 3% %NiO, 2%WO ₃ , 8%Al ₂ O ₃ , 5%SiO ₂ , 3% BaO and 2%CaO; the preparation process is as follows: batching various raw materials according to the specified ratio, ball milling, mixing, Drying and pressing to form a block green body; in the firing preparation process of the block green body, it is first heated to 800 ° C for 6 hours to form a spinel solid solution, and then continue to heat up to 1250 ° C for 6 hours to make the spinel The spar-type solid solution and silicate minerals are multi-phase composited to form a black sintered body with a multi-phase composite structure; after crushing, crushing and passing through a 450 mesh sieve, the infrared radiation powder of the multi-phase composite system is prepared.

The mass ratio of each component in the inorganic binding aid is: 30% Al ₂ O ₃ , 38% SiO ₂ , 10% MgO, 10% TiO ₂ , 2% NiO and 10% B ₂ O ₅ , which are prepared by mixing.

After the surface of the refractory substrate is purged, the above-mentioned infrared radiation coating is sprayed on the surface, and the infrared radiation coating is formed after drying and curing. The normal full band emissivity of the infrared radiation coating is 0.89, the emissivity of the 8μm~25μm band is 0.90, the emissivity of the 8μm~14μm band is 0.93, and the emissivity of the 14μm~25μm band is 0.94. The thermal conductivity of the infrared radiation coating at 1000°C is 0.30W/(m·K). The infrared radiation coating is subjected to air natural cooling thermal shock cycle in the range of normal temperature to 1200 ℃, and the coating surface has no cracks and the coating does not fall off after 30 cycles.

Example 4

According to the mass ratio, the formula is 35% spinel-silicate multiphase composite system infrared radiation powder, 15% pore-forming agent, 29% water glass, 15% water, 3% inorganic bonding agent, and 3% sodium phosphate , the above-mentioned various components are weighed according to the proportion, stirred and mixed for 5 hours, and the infrared radiation coating of viscous suspending fluid is obtained.

Wherein, the mass ratio of each component in the infrared radiation powder of the spinel-silicate multiphase composite system is:

60%Fe ₂ O ₃ , 10%Co ₂ O ₃ , 6%NiO, 2%V ₂ O ₅ , 13%Al ₂ O ₃ , 7%SiO ₂ , 1.5%TiO ₂ and 0.5%CaO; its preparation process is : All kinds of raw materials are mixed according to the specified ratio, and the ingredients are ball milled, mixed, dried and pressed to form a block body; in the process of firing the block body, it is first heated to 980 ° C for 1 hour to form Spinel-type solid solution, and then continue to heat up to 1100 ° C for 8 hours, so that the spinel-type solid solution and silicate minerals are multi-phase composited to form a black sintered body with a multi-phase composite structure; after crushing, crushing and passing through 230 mesh Sieve to prepare multi-phase composite system infrared radiation powder.

The mass ratio of each composition in the inorganic bonding aid is: 30%Al ₂ O ₃ , 40% SiO ₂ , 7%MgO, 3%TiO ₂ , 10%NiO, 5%Cr ₂ O ₃ and 5%B ₂ O ₅ , prepared by mixing.

After the surface of the refractory substrate is purged, the above-mentioned infrared radiation coating is sprayed on the surface, and the infrared radiation coating is formed after drying and curing. The normal full-band emissivity of the infrared radiation coating is 0.90, the emissivity of the 8μm~25μm band is 0.92, the emissivity of the 8μm~14μm band is 0.93, and the emissivity of the 14μm~25μm band is 0.93. The thermal conductivity of the infrared radiation coating at 1000°C is 0.27W/(m·K). The infrared radiation coating is subjected to air natural cooling thermal shock cycle in the range of normal temperature to 1200 ℃, and the coating surface has no cracks and the coating does not fall off after 30 cycles.

Example 5

According to the mass ratio, 30% spinel-silicate multiphase composite system infrared radiation powder, 5% pore forming agent, 5% potassium hexatitanate, 50% water glass, 5% water, 3.5% inorganic bonding agent , 0.5% organic bentonite, 0.5% sodium phosphate, 0.3% tributyl phosphate, and 0.2% water-based acrylic resin, weigh the above-mentioned components according to the proportion, stir and mix for 2 hours, and then obtain a viscous suspension fluid infrared radiation coatings.

Among them, the mass ratio of each component in the infrared radiation powder of the spinel-silicate multiphase composite system is: 30% Fe ₂ O ₃ , 10% MnO ₂ , 3% CuO, 2% Co ₂ O ₃ , 3% %Mo ₂ O ₃ , 2.5% V ₂ O ₅ , 2.5% WO ₃ , 25% Al ₂ O ₃ , 10% SiO ₂ , 5% MgO, 3% TiO ₂ , 1.5% BaO and 1.5% CaO; its preparation process In order to: mix various raw materials according to the specified ratio, ball mill, mix, dry and press the ingredients to form a block green body; in the process of firing and preparing the block green body, first heat it to 850 ° C for 4 hours, Form a spinel-type solid solution, and then continue to heat up to 1100°C for 8 hours, so that the spinel-type solid solution and silicate minerals are multi-phase composited to form a black sintered body with a multi-phase composite structure; after crushing, crushing and passing 300 Mesh sieve to prepare multi-phase composite system infrared radiation powder.

The mass ratio of each component in the inorganic binding aid is: 40% Al ₂ O ₃ , 40% SiO ₂ , 6% MgO, 6% TiO ₂ and 8% Cr ₂ O ₃ , which are prepared by mixing.

After the surface of the refractory substrate is purged, the above-mentioned infrared radiation coating is sprayed on the surface, and the infrared radiation coating is formed after drying and curing. The normal full-band emissivity of the infrared radiation coating is 0.88, the emissivity of the 8μm~25μm band is 0.90, the emissivity of the 8μm~14μm band is 0.92, and the emissivity of the 14μm~25μm band is 0.91. The thermal conductivity of the infrared radiation coating at 1000°C is 0.28W/(m·K). The infrared radiation coating is subjected to air natural cooling thermal shock cycle in the range of normal temperature to 1200 ℃, and the coating surface has no cracks and the coating does not fall off after 30 cycles.

Example 6

According to the mass ratio, 35% spinel-silicate multiphase composite system infrared radiation powder, 7% pore forming agent, 10% potassium hexatitanate, 30% water glass, 10% water, 7% inorganic bonding agent , 0.3% organic bentonite, 0.3% sodium phosphate, 0.2% tributyl phosphate, 0.2% water-based acrylic resin, weigh the above-mentioned various components according to the proportion, stir and mix for 2 hours, and then obtain a viscous suspension fluid infrared radiation coatings.

Among them, the mass ratio of each component in the infrared radiation powder of the spinel-silicate multiphase composite system is: 7%Fe ₂ O ₃ , 20%MnO ₂ , 6%Co ₂ O ₃ , 5.6%Mo ₂ O _3. 1.4%NiO, 6%Al ₂ O ₃ , 50%SiO ₂ , 1.5%MgO, 0.5%TiO ₂ and 2%BaO; the preparation process is: mix various raw materials according to the specified ratio, and ball mill the ingredients , mixed, dried and pressed into a block green body; in the firing preparation process of the block green body, it is first heated to 900 ° C for 6 hours to form a spinel solid solution, and then continue to heat up to 1150 ° C for 6 hours , the spinel-type solid solution and silicate minerals are multi-phase compounded to form a black sintered body with a multi-phase composite structure; after crushing, crushing and passing through a 200-mesh sieve, a multi-phase composite system infrared radiation powder is prepared.

The mass ratio of each composition in the inorganic bonding aid is: 30% Al ₂ O ₃ , 50% SiO ₂ , 8% MgO, 2% TiO ₂ , 2% NiO, 3% Cr ₂ O ₃ and 5% B ₂ O ₅ , prepared by mixing.

After the surface of the refractory substrate is purged, the above-mentioned infrared radiation coating is sprayed on the surface, and the infrared radiation coating is formed after drying and curing. The normal full band emissivity of the infrared radiation coating is 0.89, the emissivity of the 8 μm~25 μm band is 0.91, the emissivity of the 8 μm~14 μm band is 0.92, and the emissivity of the 14 μm~25 μm band is 0.93. The thermal conductivity of the infrared radiation coating at 1000°C is 0.25W/(m·K). The infrared radiation coating is subjected to air natural cooling thermal shock cycle in the range of normal temperature to 1200 ℃, and the coating surface has no cracks and the coating does not fall off after 30 cycles.

Example 7

According to the mass ratio, it is 45% spinel-silicate multiphase composite system infrared radiation powder, 10% pore forming agent, 30% water glass, 9% water, 4.5% inorganic bonding agent, 1.2% organic bentonite, 0.1 % sodium phosphate, 0.1% tributyl phosphate, and 0.1% water-based acrylic resin, weigh the above-mentioned components according to the proportion, stir and mix for 6 hours, and then the viscous suspension fluid infrared radiation coating is obtained.

Among them, the mass ratio of each component in the infrared radiation powder of the spinel-silicate multiphase composite system is: 30%MnO ₂ , 8.5%CuO, 8%Co ₂ O ₃ , 6.4%Mo ₂ O ₃ , 1.6 %NiO, 22.5%Al ₂ O ₃ , 22.5%SiO ₂ and 0.5%MgO; the preparation process is: batching various raw materials according to the specified proportion, ball milling, mixing, drying and pressing the batching into a block green body ;In the firing preparation process of the block green body, it is first heated to 900 ° C for 3 hours to form a spinel solid solution, and then continue to heat up to 1300 ° C for 4 hours to make the spinel solid solution and silicate minerals Multiphase compounding is carried out to form a black sintered body with a multiphase composite structure; through crushing, crushing and passing through a 325-mesh sieve, a multiphase composite system infrared radiation powder is prepared.

The mass ratio of each component in the inorganic binding aid is: 20% Al ₂ O ₃ , 60% SiO ₂ , 3% MgO, 7% TiO ₂ , 4% NiO and 6% Cr ₂ O ₃ , which are prepared by mixing.

After the surface of the refractory substrate is purged, the above-mentioned infrared radiation coating is sprayed on the surface, and the infrared radiation coating is formed after drying and curing. The normal full-band emissivity of the infrared radiation coating is 0.88, the emissivity of the 8μm~25μm band is 0.90, the emissivity of the 8μm~14μm band is 0.91, and the emissivity of the 14μm~25μm band is 0.93. The thermal conductivity of the infrared radiation coating at 1000°C is 0.27W/(m·K). The infrared radiation coating is subjected to air natural cooling thermal shock cycle in the range of normal temperature to 1200 ℃, and the coating surface has no cracks and the coating does not fall off after 30 cycles.

Example 8

According to the mass ratio, 30% spinel-silicate multiphase composite system infrared radiation powder, 5% pore forming agent, 15% potassium hexatitanate, 33% water glass, 7% water, 6% inorganic bonding agent , 2% organic bentonite, 1.4% sodium phosphate, 0.3% tributyl phosphate, and 0.3% water-based acrylic resin, weigh the above-mentioned components according to the proportion, stir and mix for 4 hours, and then obtain a viscous suspension fluid infrared radiation coatings.

Among them, the mass ratio of each component in the infrared radiation powder of the spinel-silicate multiphase composite system is: 47% Fe ₂ O ₃ , 25.2% MnO ₂ , 7.2% CuO, 5% V ₂ O ₅ , 3.6 %WO ₃ , 6%Al ₂ O ₃ , 5%SiO ₂ and 1%CaO; the preparation process is as follows: mix various raw materials according to the specified ratio, and ball mill, mix, dry and press the ingredients into a block billet body; in the firing preparation process of the block green body, it is first heated to 850 ° C for 6 hours to form a spinel solid solution, and then continue to heat up to 1300 ° C for 3 hours to make the spinel solid solution and silicate The minerals are multiphase compounded to form a black sintered body with a multiphase composite structure; after crushing, crushing and passing through a 400-mesh sieve, the infrared radiation powder of the multiphase composite system is prepared.

The mass ratio of each component in the inorganic bonding aid is: 35%Al ₂ O ₃ , 45% SiO ₂ , 5%MgO, 8%TiO ₂ , 4%Cr ₂ O ₃ and 3%B ₂ O ₅ , prepared by mixing made.

After the surface of the refractory substrate is purged, the above-mentioned infrared radiation coating is sprayed on the surface, and the infrared radiation coating is formed after drying and curing. The normal full-band emissivity of the infrared radiation coating is 0.90, the emissivity of the 8μm~25μm band is 0.93, the emissivity of the 8μm~14μm band is 0.94, and the emissivity of the 14μm~25μm band is 0.94. The thermal conductivity of the infrared radiation coating at 1000°C is 0.29W/(m·K). The infrared radiation coating is subjected to air natural cooling thermal shock cycle in the range of normal temperature to 1200 ℃, and the coating surface has no cracks and the coating does not fall off after 30 cycles.

The infrared radiation test proves that the infrared radiation coating formed by the present invention has excellent infrared radiation performance, low thermal conductivity and good structural stability, and its normal full-band emissivity is 0.88~0.92, 8μm~25μm The emissivity of the band is 0.90~0.93, the emissivity of the 8μm~14μm band is 0.91~0.94, and the emissivity of the 14μm~25μm band is 0.91~0.94; the thermal conductivity of the infrared radiation coating at 1000 °C is 0.25~0.31W/ (m·K). In the range of normal temperature to 1200 ℃, the air natural cooling thermal shock cycle is carried out, and the coating surface has no cracks and the coating does not fall off after 30 cycles.

The above description is only an embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention Inside.

Claims (3)

1. can form the infrared radiation coating of low thermal conductivity coating, by following component, through mixed preparing, formed, described each component and component concentration thereof are by mass percentage: the heterogeneous compound system ir radiation of spinel-silicate powder: 40%, pore-forming material: 5%, six potassium titanates: 10%, water glass: 30%, water: 5%, inorganic combination auxiliary agent: 6.7%, anti-sedimentation agent: 1%, dispersion agent: 2%, defoamer: 0.2%, flow agent: 0.1%, described pore-forming material is comprised of graphite and starch, the mass ratio of graphite and starch is 50%:50%, the preparation method of the heterogeneous compound system ir radiation of described spinel-silicate powder is: include following steps: 1) various raw materials are prepared burden to scale, again this batching is carried out to ball milling, mix, the preliminary treatment dry and compression moulding is block base substrate, described raw material comprises the A component of tangible one-tenth spinel type sosoloid, B component and the accelerant C component of formation silicate minerals, and its mass ratio is 100%:20 ~ 300%:0 ~ 15%, and wherein, described A component is Fe ₂o ₃, MnO ₂, CuO, Co ₂o ₃, Mo ₂o ₃, NiO, V ₂o ₅and WO ₃, described B component is Al ₂o ₃, SiO ₂, MgO, BaO, CaO and TiO ₂, described accelerant C component is glass powder and B ₂o ₃, each component concentration is by percentage to the quality: Fe ₂o ₃: 0 ~ 60%, MnO ₂: 0 ~ 60%, Al ₂o ₃: 5 ~ 50%, SiO ₂: 5 ~ 50%, CuO:0 ~ 12%, Co ₂o ₃: 0 ~ 10%, MgO:0 ~ 10%, Mo ₂o ₃: 0 ~ 6%, NiO:0 ~ 6%, TiO ₂: 0 ~ 6%, V ₂o ₅: 0 ~ 5%, WO ₃: 0 ~ 5%, BaO:0 ~ 3%, CaO:0 ~ 3%, glass powder: 0 ~ 3%, B ₂o ₃: 0 ~ 3%, 2) the block base substrate of step 1) gained is carried out to heating and thermal insulation in 800 ~ 980 ℃ of temperature ranges, the heating and thermal insulation time is 1 ~ 6 hour, forms spinel type sosoloid, then continue to be warmed up in 1100 ~ 1300 ℃ of temperature ranges and carry out heating and thermal insulation, be incubated 2 ~ 8 hours, form silicate minerals, spinel type sosoloid and silicate minerals are carried out heterogeneous compound, form the black sintered compact of heterogeneous composite structure, 3) by step 2) gained black sintered compact is through fragmentation, pulverizing and cross 200 ~ 500 sieves, obtains the heterogeneous compound system ir radiation of spinel-silicate powder, and described inorganic combination auxiliary agent is formed through mixed preparing by following component: Al ₂o ₃: 20 ~ 40%, SiO ₂: 20 ~ 60%, MgO:2 ~ 10%, TiO ₂: 2 ~ 10%, NiO:0 ~ 10%, Cr ₂o ₃: 0 ~ 10%, B ₂o ₅: 0 ~ 10%, be more than mass percent meter.

2. by the infrared radiation coating that can form low thermal conductivity coating claimed in claim 1, it is characterized in that described inorganic combination adjuvant component is preferably: Al ₂o ₃: 20%, SiO ₂: 60%, MgO:5%, TiO ₂: 2%, NiO:5%, Cr ₂o ₃: 5%, B ₂o ₅: 3%, be more than mass percent meter.

3. by the infrared radiation coating that can form low thermal conductivity coating claimed in claim 1, it is characterized in that described anti-sedimentation agent is organobentonite; Described dispersion agent is sodium phosphate; Described defoamer is tributyl phosphate; Described flow agent is water-borne acrylic resin.