Enamel material and preparation method thereof

Abstract

The invention discloses an enamel material and a preparation method thereof, and belongs to the technical field of enamel materials, and the enamel material comprises the following components in parts by weight: 100 parts of basic glaze, 5-7 parts of lithium-based bentonite, 1.2-2.2 parts of a carbon nanotube composite material, 0.1-0.5 part of an auxiliary agent, and 55-65 parts of deionized water. Wherein concentrated nitric acid and polyvinylpyrrolidone are added into carbon nanotubes to obtain non-covalent modified carbon nanotubes, and then the non-covalent modified carbon nanotubes are sequentially coated with nano titanium dioxide and nano silicon dioxide through a sol-gel method to obtain the carbon nanotube composite material. The method for preparing the enamel material comprises the following steps: firstly, pretreating a steel plate, then putting the basic glaze, the lithium-based bentonite, the auxiliary agent, the carbon nanotube composite material and the deionized water into an ultrasonic cleaning machine for ultrasonic dispersion for 40-60 minutes, grinding for 3-5 hours, sieving to obtain enamel glaze slip, uniformly coating the pretreated steel plate with the obtained enamel glaze slip, and drying to obtain the enamel material. And sintering in a vacuum high-temperature sintering furnace at a heating speed of 3-3.4 DEG C / min, preserving heat, and cooling to obtain the enamel material.

Description

Technical Field

[0001] The invention belongs to the technical field of enamel materials, and particularly relates to an enamel material and a preparation method thereof. Background Art

[0002] Traditional enamel materials are formed by coating glaze on a metal base surface and sintering it at high temperature. Its unique glass properties not only make the surface look smooth and strong, but also have the characteristics of high hardness, high temperature resistance, corrosion resistance, and easy processing. It is widely used in daily furniture, building decoration, medical machinery, high-temperature anti-corrosion equipment and electronic components. When enamel materials also have characteristics such as sterilization, photocatalytic degradation, and electrical properties, they also show application potential in the fields of building exterior wall decoration, sanitary ware and artificial intelligence. Constructing a multi-component micro-nano composite material on the enamel surface can give it unique optical, electrical, toughness and chemical properties, realizing multifunctional expansion. For example, Chinese patent CN114180839 discloses a particle-toughened enamel glaze slurry, enamel plate and preparation method. The nano-alumina used only relies on the single-point action of crack deflection and particle pinning for toughening, and relies on the physical suspension of clay, and the adhesion is not strong; Composite materials are new materials composed of two or more different types of materials. Through their mutual combination, the advantages of various materials can be fully utilized. Composite material combinations usually include a main matrix material and one or more reinforcing materials. Carbon nanotubes as reinforcing materials can significantly improve the performance of the matrix material, and improve its mechanical properties and electrochemical properties such as strength, hardness, and conductivity. Carbon nanotube composite materials with carbon nanotubes as reinforcing materials have many excellent performance characteristics, including excellent mechanical properties, electrical conductivity, thermal properties, etc., and have shown broad application prospects in many fields. For example, Chinese patent CN118459092A discloses a carbon nanotube composite material and its preparation method and application. In the invention, through the combined action of a specific content of acidified and carboxylated carbon nanotubes and enamel powder, the carboxyl group and the metal oxide in the enamel only form hydrogen bonds, which are much weaker than covalent bonds, and the adhesion to the steel plate matrix is ​​not strong. Therefore, the present invention develops an enamel material and a preparation method thereof, which are used to solve the problems of poor toughening effect and weak adhesion to the steel plate substrate in the prior art. Summary of the Invention

[0003] The object of the present invention is to provide an enamel material and a preparation method thereof, which are used to solve the problems of poor toughening effect and weak adhesion to the steel plate substrate in the prior art.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: An enamel material comprises the following components in parts by weight: 100 parts of basic glaze, 5-7 parts of lithium-based bentonite, 1.2-2.2 parts of carbon nanotube composite material, 0.1-0.5 parts of auxiliary agent, and 55-65 parts of deionized water.

[0005] Preferably, the basic glaze comprises the following components in parts by weight: 10.0-18.0 parts of boron trioxide, 8.0-11.0 parts of sodium oxide, 2.0-3.0 parts of magnesium oxide, 2.0-3.0 parts of aluminum trioxide, 30.0-45.0 parts of silicon dioxide, 1-2 parts of lithium oxide, 1-2.5 parts of potassium oxide, 2.0-3.0 parts of phosphorus pentoxide, 1.0-2.0 parts of zinc oxide, 15.0-20.0 parts of titanium dioxide and 5.0-10.0 parts of sodium fluorosilicate.

[0006] Preferably, the method for preparing the carbon nanotube composite material comprises the following steps: Step 1: adding carbon nanotubes to concentrated nitric acid at 115-125° C. for 1-2 hours, cooling, and filtering to obtain a filter cake, washing the filter cake with 4-6% sodium hydroxide for 1-3 times, then washing it with deionized water for 1-3 times, drying it at 75-85° C. for 8-12 hours, and then ultrasonically dispersing it with polyvinyl pyrrolidone in deionized water for 12-24 hours, filtering it through a 0.2 μm porous filter membrane, washing it, and drying it to obtain non-covalently modified carbon nanotubes; Step 2: Ultrasonic dispersion of the product of step 1 in 8-12 wt% isopropanol solution for 20-30 min, adjusting the pH to 2-2.4, adding tetrabutyl titanate, stirring at room temperature for 2-4 h, filtering to obtain a filter cake, washing the filter cake alternately with anhydrous ethanol and deionized water for 2-4 times, drying at 95-105° C. for 2-3 h, and finally sintering to 440-480° C. in vacuum at a heating rate of 5-10° C. / min, and keeping the temperature for 2-6 h to obtain titanium dioxide / non-covalently modified carbon nanotubes; Step 3: Stir ethyl orthosilicate and anhydrous ethanol at 55-65°C for 2-4 hours to obtain solution A, then stir the product of step 2, polyvinyl pyrrolidone and deionized water at room temperature for 10-30 minutes, add solution A, stir at 38-42°C for 1-3 hours, centrifuge, separate the liquids to obtain a filter cake, wash the filter cake alternately with anhydrous ethanol and deionized water 2-4 times, dry at 50-55°C for 1-3 hours, and finally sinter under vacuum at 360-385°C for 2-4 hours to obtain a carbon nanotube composite material.

[0007] Preferably, in step 1, the usage ratio of carbon nanotubes, concentrated nitric acid, and polyvinyl pyrrolidone is 1 g:100 mL:25-36 mg.

[0008] Preferably, in step 2, the usage ratio of the product of step 1 to tetrabutyl titanate is 1 g:80-90 mL.

[0009] Preferably, the usage ratio of ethyl orthosilicate in step 3, the product of step 2 and polyvinyl pyrrolidone is 72-80 mL: 1 g: 18-24 mg.

[0010] Preferably, the auxiliary agent is one or more of potassium fluorosilicate, potassium chloride and potassium carbonate.

[0011] A method for preparing an enamel material comprises the following steps: The first step is to sandblast the steel plate with white jade steel, then clean the surface of the steel plate with anhydrous ethanol and acetone, and dry it to obtain a pretreated steel plate; The second step is to put the base glaze, lithium bentonite, additives, carbon nanotube composite material and deionized water into an ultrasonic cleaning machine for ultrasonic dispersion for 40-60 minutes, grind for 3-5 hours, and pass through an 80-160 mesh sieve to obtain an enamel glaze slurry; The third step is to evenly apply the enamel slurry on the pretreated steel plate, dry it, and sinter it in a vacuum high-temperature sintering furnace at a heating rate of 3-3.4°C / min, keep it warm, and cool it to obtain the enamel material.

[0012] Preferably, the drying temperature is 55-65° C. and the drying time is 30-50 min.

[0013] Preferably, the holding temperature is 790-840° C., and the holding time is 5-6 minutes.

[0014] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: The present invention uses lithium-based bentonite, carbon nanotube composite materials, additives and basic glazes of specific composition to work synergistically. The lithium-based bentonite can improve the stability and rheological properties of the glaze, prevent solid particles from settling, ensure uniform coating, and enhance the bonding force between the glaze layer and the steel plate substrate in the early stages of drying and sintering, reducing the risk of cracking. The carbon nanotube composite material serves as a core toughening and interface reinforcement phase. In the enamel glaze layer, the carbon nanotubes form a three-dimensional network in the glaze layer, which can effectively bridge microcracks and hinder the expansion of cracks. In addition, the carbon nanotubes work together with the toughness network formed by phosphorus pentoxide in the basic glaze to significantly improve the toughness and impact resistance of the glaze layer. The outermost layer of nano-silicon dioxide particles will be evenly dispersed and attached to the grain boundaries of the basic glaze grains during the sintering process, inhibiting the abnormal growth of the grains, which not only improves the hardness, At the same time, when hard nano-silica particles attach to the grain boundaries, they will generate a local compressive stress field on the surrounding matrix grains, and tensile stress will also be generated inside the matrix grains. These tensile stresses will cause the matrix grains to form many sub-grain boundaries with different directions, forcing the cracks to advance along a more tortuous path and increasing the possibility of the cracks directly passing through the interior of the grains rather than just extending along the grain boundaries, effectively absorbing and dissipating fracture energy, and synergistically achieving multi-scale toughening of the material; the flexible carbon nanotubes of nano-titania provide rigid support to prevent it from bending, breaking or agglomerating due to melt flow or grain extrusion during the glaze sintering process, and the surface of nano-titania is rich in hydroxyl groups, which can be tightly bonded to the nano-silica layer through chemical bonds (Ti-O-Si bonds). When the cracks extend to the vicinity of the carbon nanotubes, they can also promote crack deflection. DETAILED DESCRIPTION

[0015] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0016] Carbon nanotubes are produced by Zhongke Nano-Times, model IM299CP, with a purity of >99%, an outer diameter of 5-15nm, a length of 10-20um, and a specific surface area of ​​260-330m 2 / g.

[0017] Example 1: This example provides a method for preparing a carbon nanotube composite material, comprising the following steps: Step 1: Add 2 g of carbon nanotubes to 200 mL of concentrated nitric acid at 115 ° C for 1 hour, cool and filter to obtain a filter cake, wash the filter cake once with 50 mL of 4% sodium hydroxide, then wash it once with 50 mL of deionized water, dry it at 75 ° C for 8 hours, and then ultrasonically disperse it with 50 mg of polyvinyl pyrrolidone in 4 L of deionized water for 12 hours, filter it through a 0.2 μm porous filter membrane, wash it, and dry it to obtain non-covalently modified carbon nanotubes; Step 2: Ultrasonic dispersion of 2 g of the product of step 1 in 100 mL of 8 wt% isopropanol solution for 20 min, adjusting the pH to 2, adding 160 mL of tetrabutyl titanate, stirring at 25 ° C for 2 h, filtering to obtain a filter cake, and washing the filter cake twice with 50 mL of anhydrous ethanol and 50 mL of deionized water alternately, drying at 95 ° C for 2 h, and finally sintering to 440 ° C in vacuum at a heating rate of 5 ° C / min, and keeping warm for 2 h to obtain titanium dioxide / non-covalently modified carbon nanotubes; Step 3: Stir 72 mL of ethyl orthosilicate and 300 mL of anhydrous ethanol at 55 ° C for 2 h to obtain solution A, then stir 1 g of the product of step 2, 18 mg of polyvinyl pyrrolidone and 3.5 L of deionized water at 25 ° C for 10 min, add solution A, stir at 38 ° C for 1 h, centrifuge, separate the liquid to obtain a filter cake, wash the filter cake twice with 50 mL of anhydrous ethanol and 50 mL of deionized water alternately, dry at 50 ° C for 1 h, and finally sinter at 360 ° C in vacuum for 2 h to obtain a carbon nanotube composite material.

[0018] This embodiment provides a method for preparing an enamel material, comprising the following steps: The first step is to sandblast the BTC1 cold-rolled steel plate with white jade steel, then clean the surface of the steel plate with anhydrous ethanol and acetone, and dry it to obtain a pretreated steel plate; In the second step, 100 parts of basic glaze, 5 parts of lithium bentonite, 1.2 parts of carbon nanotube composite material, 0.1 part of potassium carbonate and 55 parts of deionized water were mixed.

[0019] The mixture was placed in an ultrasonic cleaning machine for ultrasonic dispersion for 40 min, ground for 3 h, and passed through an 80-mesh sieve to obtain an enamel glaze slurry; The third step is to evenly apply the enamel slurry on the pretreated steel plate, dry it at 55°C for 30 minutes, and sinter it in a vacuum high-temperature sintering furnace at a heating rate of 3°C / min. The holding temperature is 790°C and the holding time is 5 minutes. Then cool it to obtain the enamel material.

[0020] The basic glaze is composed of 10.0 parts of boron trioxide, 8.0 parts of sodium oxide, 2.0 parts of magnesium oxide, 2.0 parts of aluminum trioxide, 30.0 parts of silicon dioxide, 1 part of lithium oxide, 1 part of potassium oxide, 2.0 parts of phosphorus pentoxide, 1.0 part of zinc oxide, 15.0 parts of titanium dioxide and 5.0 parts of sodium fluorosilicate.

[0021] Example 2: This example provides a method for preparing a carbon nanotube composite material, comprising the following steps: Step 1: Add 2 g of carbon nanotubes to 200 mL of concentrated nitric acid at 125 ° C for 2 hours, cool and filter to obtain a filter cake, wash the filter cake three times with 50 mL of 6% sodium hydroxide, then wash it three times with 50 mL of deionized water, dry it at 85 ° C for 12 hours, and then ultrasonically disperse it with 72 mg of polyvinyl pyrrolidone in 4 L of deionized water for 24 hours, filter it through a 0.2 μm porous filter membrane, wash it, and dry it to obtain non-covalently modified carbon nanotubes; Step 2: Ultrasonic dispersion of 2 g of the product from step 1 in 100 mL of 12 wt% isopropanol solution for 30 min, adjusting the pH to 2.4, adding 180 mL of tetrabutyl titanate, stirring at 25 ° C for 4 h, filtering to obtain a filter cake, and washing the filter cake alternately with 50 mL of anhydrous ethanol and 50 mL of deionized water 4 times, drying at 105 ° C for 3 h, and finally sintering to 480 ° C in vacuum at a heating rate of 10 ° C / min, and keeping warm for 6 h to obtain titanium dioxide / non-covalently modified carbon nanotubes; Step 3: Stir 80 mL of ethyl orthosilicate and 300 mL of anhydrous ethanol at 65 ° C for 4 hours to obtain solution A, then stir 1 g of the product of step 2, 24 mg of polyvinyl pyrrolidone and 3.5 L of deionized water at 25 ° C for 30 minutes, add solution A, stir at 42 ° C for 3 hours, centrifuge, separate the liquid to obtain a filter cake, wash the filter cake alternately with 50 mL of anhydrous ethanol and 50 mL of deionized water 4 times, dry at 55 ° C for 3 hours, and finally sinter under vacuum at 385 ° C for 4 hours to obtain a carbon nanotube composite material.

[0022] This embodiment provides a method for preparing an enamel material, comprising the following steps: The first step is to sandblast the BTC1 cold-rolled steel plate with white jade steel, then clean the surface of the steel plate with anhydrous ethanol and acetone, and dry it to obtain a pretreated steel plate; In the second step, 100 parts of basic glaze, 7 parts of lithium bentonite, 2.2 parts of carbon nanotube composite material, 0.5 parts of potassium carbonate and 65 parts of deionized water were mixed.

[0023] The mixture was placed in an ultrasonic cleaning machine for ultrasonic dispersion for 60 min, ground for 5 h, and passed through a 160-mesh sieve to obtain an enamel glaze slurry. The third step is to evenly apply the enamel slurry on the pretreated steel plate, dry it at 65°C for 50 minutes, and sinter it in a vacuum high-temperature sintering furnace at a heating rate of 3.4°C / min. The holding temperature is 840°C and the holding time is 6 minutes. Then cool it to obtain the enamel material.

[0024] The basic glaze comprises 18.0 parts of boron trioxide, 11.0 parts of sodium oxide, 3.0 parts of magnesium oxide, 3.0 parts of aluminum trioxide, 45.0 parts of silicon dioxide, 2 parts of lithium oxide, 2.5 parts of potassium oxide, 3.0 parts of phosphorus pentoxide, 2.0 parts of zinc oxide, 20.0 parts of titanium dioxide and 10.0 parts of sodium fluorosilicate.

[0025] Example 3: This example provides a method for preparing a carbon nanotube composite material, comprising the following steps: Step 1: Add 2 g of carbon nanotubes to 200 mL of concentrated nitric acid at 120 ° C for 1.5 hours, cool and filter to obtain a filter cake, wash the filter cake twice with 50 mL of 5% sodium hydroxide, then wash it twice with 50 mL of deionized water, dry it at 80 ° C for 10 hours, and then ultrasonically disperse it with 60 mg of polyvinyl pyrrolidone in 4 L of deionized water for 15 hours, filter it through a 0.2 μm porous filter membrane, wash it, and dry it to obtain non-covalently modified carbon nanotubes; Step 2: Ultrasonic dispersion of 2 g of the product of step 1 in 100 mL of 10 wt% isopropanol solution for 25 min, adjusting the pH to 2.2, adding 170 mL of tetrabutyl titanate, stirring at 25 ° C for 3 h, filtering to obtain a filter cake, and washing the filter cake alternately with 50 mL of anhydrous ethanol and 50 mL of deionized water three times, drying at 100 ° C for 2.5 h, and finally sintering to 460 ° C in vacuum at a heating rate of 8 ° C / min, and keeping warm for 4 h to obtain titanium dioxide / non-covalently modified carbon nanotubes; Step 3: Stir 76 mL of ethyl orthosilicate and 300 mL of anhydrous ethanol at 55 ° C for 3 hours to obtain solution A, then stir 1 g of the product of step 2, 20 mg of polyvinyl pyrrolidone and 3.5 L of deionized water at 25 ° C for 20 minutes, add solution A, stir at 40 ° C for 2 hours, centrifuge, separate the liquid to obtain a filter cake, wash the filter cake three times with 50 mL of anhydrous ethanol and 50 mL of deionized water alternately, dry at 52 ° C for 2 hours, and finally sinter at 380 ° C in vacuum for 3 hours to obtain a carbon nanotube composite material.

[0026] This embodiment provides a method for preparing an enamel material, comprising the following steps: The first step is to sandblast the BTC1 cold-rolled steel plate with white jade steel, then clean the surface of the steel plate with anhydrous ethanol and acetone, and dry it to obtain a pretreated steel plate; In the second step, 100 parts of basic glaze, 6 parts of lithium bentonite, 1.6 parts of carbon nanotube composite material, 0.4 parts of potassium carbonate and 60 parts of deionized water were mixed.

[0027] The mixture was placed in an ultrasonic cleaning machine for ultrasonic dispersion for 50 min, ground for 4 h, and passed through a 120-mesh sieve to obtain an enamel glaze slurry; The third step is to evenly apply the enamel slurry on the pretreated steel plate, dry it at 60°C for 40 minutes, and sinter it in a vacuum high-temperature sintering furnace at a heating rate of 3.2°C / min. The holding temperature is 820°C and the holding time is 5.5 minutes. Then cool it to obtain the enamel material.

[0028] The basic glaze is 12 parts of boron trioxide, 10 parts of sodium oxide, 2.5 parts of magnesium oxide, 2.8 parts of aluminum trioxide, 40 parts of silicon dioxide, 1.5 parts of lithium oxide, 2 parts of potassium oxide, 2.5 parts of phosphorus pentoxide, 1.5 parts of zinc oxide, 18 parts of titanium dioxide and 8 parts of sodium fluorosilicate.

[0029] Comparative Example 1: This comparative example provides a method for preparing a carbon nanotube composite material, comprising the following steps: Step 1: Add 2 g of carbon nanotubes to 200 mL of concentrated nitric acid at 120 ° C for 1.5 hours, cool and filter to obtain a filter cake, wash the filter cake twice with 50 mL of 5% sodium hydroxide, then wash it twice with 50 mL of deionized water, dry it at 80 ° C for 10 hours, and then ultrasonically disperse it with 60 mg of polyvinyl pyrrolidone in 4 L of deionized water for 15 hours, filter it through a 0.2 μm porous filter membrane, wash it, and dry it to obtain non-covalently modified carbon nanotubes; Step 2: Stir 76 mL of ethyl orthosilicate and 300 mL of anhydrous ethanol at 55 ° C for 3 hours to obtain solution A, then stir 1 g of the product of step 1, 20 mg of polyvinyl pyrrolidone and 3.5 L of deionized water at 25 ° C for 20 minutes, add solution A, stir at 40 ° C for 2 hours, centrifuge, separate the liquid to obtain a filter cake, wash the filter cake three times with 50 mL of anhydrous ethanol and 50 mL of deionized water alternately, dry at 52 ° C for 2 hours, and finally sinter at 380 ° C in vacuum for 3 hours to obtain a carbon nanotube composite material.

[0030] This comparative example provides a method for preparing an enamel material, comprising the following steps: The first step is to sandblast the BTC1 cold-rolled steel plate with white jade steel, then clean the surface of the steel plate with anhydrous ethanol and acetone, and dry it to obtain a pretreated steel plate; In the second step, 100 parts of basic glaze, 6 parts of lithium bentonite, 1.6 parts of carbon nanotube composite material, 0.4 parts of potassium carbonate and 60 parts of deionized water were mixed.

[0031] The mixture was placed in an ultrasonic cleaning machine for ultrasonic dispersion for 50 min, ground for 4 h, and passed through a 120-mesh sieve to obtain an enamel glaze slurry; The third step is to evenly apply the enamel slurry on the pretreated steel plate, dry it at 60°C for 40 minutes, and sinter it in a vacuum high-temperature sintering furnace at a heating rate of 3.2°C / min. The holding temperature is 820°C and the holding time is 5.5 minutes. Then cool it to obtain the enamel material.

[0032] The basic glaze is 12 parts of boron trioxide, 10 parts of sodium oxide, 2.5 parts of magnesium oxide, 2.8 parts of aluminum trioxide, 40 parts of silicon dioxide, 1.5 parts of lithium oxide, 2 parts of potassium oxide, 2.5 parts of phosphorus pentoxide, 1.5 parts of zinc oxide, 18 parts of titanium dioxide and 8 parts of sodium fluorosilicate.

[0033] Comparative Example 2: This comparative example provides a method for preparing a carbon nanotube composite material, comprising the following steps: Step 1: Add 2 g of carbon nanotubes to 200 mL of concentrated nitric acid at 120 ° C for 1.5 hours, cool and filter to obtain a filter cake, wash the filter cake twice with 50 mL of 5% sodium hydroxide, then wash it twice with 50 mL of deionized water, dry it at 80 ° C for 10 hours, and then ultrasonically disperse it with 60 mg of polyvinyl pyrrolidone in 4 L of deionized water for 15 hours, filter it through a 0.2 μm porous filter membrane, wash it, and dry it to obtain non-covalently modified carbon nanotubes; Step 2: Ultrasonic disperse 2 g of the product of step 1 in 100 mL of 10 wt% isopropanol solution for 25 min, adjust the pH value to 2.2, add 170 mL of tetrabutyl titanate, stir at 25 ° C for 3 h, filter to obtain a filter cake, wash the filter cake alternately with 50 mL of anhydrous ethanol and 50 mL of deionized water three times, dry at 100 ° C for 2.5 h, and finally sinter to 460 ° C in vacuum at a heating rate of 8 ° C / min, and keep warm for 4 h to obtain titanium dioxide / non-covalently modified carbon nanotubes.

[0034] This comparative example provides a method for preparing an enamel material, comprising the following steps: The first step is to sandblast the BTC1 cold-rolled steel plate with white jade steel, then clean the surface of the steel plate with anhydrous ethanol and acetone, and dry it to obtain a pretreated steel plate; In the second step, 100 parts of basic glaze, 6 parts of lithium bentonite, 1.6 parts of carbon nanotube composite material, 0.4 parts of potassium carbonate and 60 parts of deionized water were mixed.

[0035] The mixture was placed in an ultrasonic cleaning machine for ultrasonic dispersion for 50 min, ground for 4 h, and passed through a 120-mesh sieve to obtain an enamel glaze slurry; The third step is to evenly apply the enamel slurry on the pretreated steel plate, dry it at 60°C for 40 minutes, and sinter it in a vacuum high-temperature sintering furnace at a heating rate of 3.2°C / min. The holding temperature is 820°C and the holding time is 5.5 minutes. Then cool it to obtain the enamel material.

[0036] The basic glaze is 12 parts of boron trioxide, 10 parts of sodium oxide, 2.5 parts of magnesium oxide, 2.8 parts of aluminum trioxide, 40 parts of silicon dioxide, 1.5 parts of lithium oxide, 2 parts of potassium oxide, 2.5 parts of phosphorus pentoxide, 1.5 parts of zinc oxide, 18 parts of titanium dioxide and 8 parts of sodium fluorosilicate.

[0037] Comparative Example 3: This comparative example provides a method for preparing an enamel material, comprising the following steps: The first step is to sandblast the BTC1 cold-rolled steel plate with white jade steel, then clean the surface of the steel plate with anhydrous ethanol and acetone, and dry it to obtain a pretreated steel plate; The second step is to mix 100 parts of basic glaze, 6 parts of lithium bentonite, 0.4 parts of potassium carbonate and 60 parts of deionized water.

[0038] The mixture was placed in an ultrasonic cleaning machine for ultrasonic dispersion for 50 min, ground for 4 h, and passed through a 120-mesh sieve to obtain an enamel glaze slurry; The third step is to evenly apply the enamel slurry on the pretreated steel plate, dry it at 60°C for 40 minutes, and sinter it in a vacuum high-temperature sintering furnace at a heating rate of 3.2°C / min. The holding temperature is 820°C and the holding time is 5.5 minutes. Then cool it to obtain the enamel material.

[0039] The basic glaze is 12 parts of boron trioxide, 10 parts of sodium oxide, 2.5 parts of magnesium oxide, 2.8 parts of aluminum trioxide, 40 parts of silicon dioxide, 1.5 parts of lithium oxide, 2 parts of potassium oxide, 2.5 parts of phosphorus pentoxide, 1.5 parts of zinc oxide, 18 parts of titanium dioxide and 8 parts of sodium fluorosilicate.

[0040] Comparative Example 4: Compared with Example 3, the "lithium bentonite" in Example 3 is replaced by "kaolin", and the remaining raw materials and preparation process are the same as Example 3.

[0041] The enamel materials obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were tested. The adhesion test was carried out in accordance with GB / T 5210-2006 "Paints and varnishes adhesion test by pull-off method"; the hardness test was carried out in accordance with GB / T 9790-2021 "Vickers and Knoop microhardness test for metals and other inorganic coatings". Polishing and grinding were performed before testing; the fracture toughness was measured using the three-point bending method.

[0042] The test results are shown in Table 1: Table 1 project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Adhesion (MPa) 7.4 7.8 7.9 6.4 6.2 5.8 6.0 Vickers hardness (HV) 604.8 542.6 584.4 544.8 572.6 534.2 575.4 <![CDATA[Fracture toughness (MPa / m 1 / 2 )]]> 19.84 20.68 20.46 19.22 19.04 18.16 19.68 As can be seen from Table 1, compared with Comparative Examples 1-4, the enamel materials prepared in Examples 1-3 have an adhesion of 7.4-7.9 MPa, a Vickers hardness (HV) of 542.6-604.8, and a fracture toughness of 19.84-20.68 MPa / m 1 / 2 It can be seen that the enamel material prepared by the present invention has good adhesion, Vickers hardness and fracture toughness.

[0043] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0044] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An enamel material, characterized in that: The invention comprises the following components in parts by weight: 100 parts of basic glaze, 5-7 parts of lithium bentonite, 1.2-2.2 parts of carbon nanotube composite material, 0.1-0.5 parts of auxiliary agent and 55-65 parts of deionized water.

2. The enamel material according to claim 1, characterized in that: The basic glaze comprises the following components in parts by weight: 10.0-18.0 parts of boron trioxide, 8.0-11.0 parts of sodium oxide, 2.0-3.0 parts of magnesium oxide, 2.0-3.0 parts of aluminum trioxide, 30.0-45.0 parts of silicon dioxide, 1-2 parts of lithium oxide, 1-2.5 parts of potassium oxide, 2.0-3.0 parts of phosphorus pentoxide, 1.0-2.0 parts of zinc oxide, 15.0-20.0 parts of titanium dioxide and 5.0-10.0 parts of sodium fluorosilicate.

3. The enamel material according to claim 1, characterized in that: A method for preparing a carbon nanotube composite material comprises the following steps: Step 1: adding carbon nanotubes to concentrated nitric acid at 115-125° C. for 1-2 hours, cooling, filtering, and obtaining a filter cake. The filter cake is alkali-washed, washed with water, and dried, and then ultrasonically dispersed with polyvinyl pyrrolidone in deionized water for 12-24 hours, filtered, washed, and dried to obtain non-covalently modified carbon nanotubes. Step 2: Ultrasonic dispersion of the product of step 1 in an 8-12 wt% isopropanol solution, adjusting the pH to 2-2.4, adding tetrabutyl titanate, stirring at room temperature for 2-4 hours, filtering to obtain a filter cake, washing the filter cake, drying it, and finally sintering it to 440-480° C. in a vacuum at a heating rate of 5-10° C. / min, and keeping it warm for 2-6 hours to obtain titanium dioxide / non-covalently modified carbon nanotubes; Step 3: Stir ethyl orthosilicate and anhydrous ethanol at 55-65°C for 2-4 hours to obtain solution A, then stir the product of step 2, polyvinyl pyrrolidone and deionized water at room temperature for 10-30 minutes, add solution A, stir at 38-42°C for 1-3 hours, centrifuge, separate the liquids to obtain a filter cake, wash the filter cake alternately with anhydrous ethanol and deionized water, dry at 50-55°C for 1-3 hours, and finally sinter under vacuum at 360-385°C for 2-4 hours to obtain a carbon nanotube composite material.

4. The enamel material according to claim 3, characterized in that: In the step 1, the usage ratio of carbon nanotubes, concentrated nitric acid, and polyvinyl pyrrolidone is 1 g:100 mL:25-36 mg.

5. The enamel material according to claim 3, characterized in that: In the step 2, the usage ratio of the product of step 1 to tetrabutyl titanate is 1 g:80-90 mL.

6. The enamel material according to claim 3, characterized in that: The usage ratio of the ethyl orthosilicate in step 3, the product of step 2 and polyvinyl pyrrolidone is 72-80 mL: 1 g: 18-24 mg.

7. The enamel material according to claim 3, characterized in that: The auxiliary agent is one or more of potassium fluorosilicate, potassium chloride and potassium carbonate.

8. The method for preparing an enamel material according to claims 1 to 7, characterized in that: The following steps are involved: The first step is to sandblast the steel plate with white jade steel, then clean the surface of the steel plate with anhydrous ethanol and acetone, and dry it to obtain a pretreated steel plate; The second step is to put the base glaze, lithium bentonite, additives, carbon nanotube composite material and deionized water into an ultrasonic cleaning machine for ultrasonic dispersion for 40-60 minutes, grind for 3-5 hours, and sieve to obtain enamel glaze slurry; The third step is to evenly apply the enamel slurry on the pretreated steel plate, dry it, and sinter it in a vacuum high-temperature sintering furnace at a heating rate of 3-3.4°C / min, keep it warm, and cool it to obtain the enamel material.

9. The method for preparing an enamel material according to claim 8, characterized in that: The drying temperature is 55-65℃ and the drying time is 30-50min.

10. The method for preparing an enamel material according to claim 8, characterized in that: The holding temperature is 790-840°C, and the holding time is 4.6-5.5 minutes.