A method for repairing a blank

Abstract

The present invention discloses a method for repairing a green body, comprising: ball-milling and sieving 20-35 parts by weight of kaolin, 10-30 parts of albite, 0.5-2 parts of talc, 15-25 parts of clay, 20-35 parts of quartz, 1-4 parts of wollastonite, and 10-15 parts of kyanite powder to obtain a prefabricated slurry; ball-milling and sieving 10-25 parts of refractory wool, and then adding a colorant to the prefabricated slurry to obtain the repair slurry; applying the repair slurry to the area to be repaired, glazing, and then firing the repaired green body to 1100°C-1315°C using a staged temperature-raising method. The repair method provided by the present invention can alleviate defects such as green body cracking and high-temperature deformation, reduce color difference, and expand the range of green body crack repair, thereby preventing the green body from cracking.

Description

Technical Field

[0001] The present invention relates to the technical field of blank repair, and in particular to a blank repair method. Background Art

[0002] Green body cracking is one of the common defects in the production of ceramic products. The main causes of green body cracking are uneven green body thickness, uneven shrinkage and drying inside the green body, too high moisture content of the green body entering the kiln, unreasonable raw material composition and firing system, etc.

[0003] A prior art patent, filed on November 6, 2009, and published with publication number CN101717268B, discloses a ceramic clay patch material, its preparation method, and a repair process. By slightly enlarging cracks in a ceramic body, stress concentration at the cracks is eliminated. Filling the cracks with the ceramic clay patch material changes the spatial connection between the particles. This method requires enlarging the cracks first, and the resulting cracks are relatively narrow.

[0004] In the prior art, a patent with an application date of 2023.06.07 and publication number CN119100843A discloses a method for repairing defects in porcelain. This method uses refractory wool to first fill the bald spots or brown spots in the porcelain blank, then fills them with hot repair mud, and then covers the filled areas with repair glaze balls. After polishing, they are recycled for the second time, which greatly improves the qualified rate of the bald spots or brown spots in the porcelain blank after repair and re-firing.

[0005] The existing repair method is prone to produce concave and convex defects in the blank during firing, and the repaired area is prone to color difference. The crack range of the repaired blank is within 2 mm and the firing temperature is below 1100°C.

[0006] Therefore, it is an urgent problem to expand the scope of repairing the cracks in the blank, increase the firing temperature and reduce the concave-convex defects and cracks in the repaired area of ​​the blank, reduce the color difference and make the blank smoother and more beautiful when fired. Summary of the Invention

[0007] Therefore, the technical problem to be solved by the present invention is to overcome the problems in the prior art of repairing cracked blanks, such as low firing temperature, narrow crack range, and the easy generation of defects such as bumps and cracks during firing. Based on this, the present invention provides a method for repairing blanks.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] S1. Clean the damaged area of ​​the green body to be repaired and weigh 20-35 parts of kaolin, 10-30 parts of albite, 0.5-2 parts of talc, 15-25 parts of clay, 20-35 parts of quartz, 1-4 parts of wollastonite, and 10-15 parts of kyanite powder as pre-made powders, and ball mill them in a ratio of pre-made powder: ball mill: water by weight = 1:1.5:0.6. The median diameter of the pre-made powders is ball milled to 6-12 μm, and then passed through a 60-100 mesh sieve to obtain a pre-made slurry;

[0010] S2. After ball milling and sieving 10-25 parts of refractory cotton, add it to the prefabricated slurry, add colorant, stir evenly, and sieve to obtain a repair slurry. The ball milling and sieving process is to add refractory cotton, water and ball mill in a ratio of refractory cotton: ball mill: water = 1:5:10 by weight, and ball mill for 5-10 minutes, and pass through a 60-100 mesh sieve;

[0011] S3. After drying the repair slurry, apply it to the damaged area of ​​the green body to be repaired, and after glazing, use a staged firing method to fire it to 1100-1315°C to obtain a repaired green body. Furthermore, the specific steps of firing it to 1100-1315°C by the staged firing method are: firing it to 500-600°C at a rate of 3-5°C / min at room temperature, then heating it to 1100-1315°C at a rate of 2-3°C / min and keeping it warm for 1h, and then quickly cooling it to 500-600°C at a rate of 5-6°C / min after keeping it warm for 1h, and finally cooling it to 50-70°C over 3-4h.

[0012] An improper firing schedule can cause cracking in the repaired body. When heating at room temperature to 500-600°C at a rate of 3-5°C / min, the prolonged heating time expels free and bound water, slowing shrinkage. Quartz in the body modifies the body's plasticity and reduces shrinkage during drying, shortening drying time and preventing deformation. However, during firing, crystal transformations occur, causing volume changes. Slow heating provides ample time for these changes, preventing excessive volume expansion caused by rapid heating, which could lead to deformation or cracking. A subsequent slow heating at a rate of 2-3°C / min to 1100-1315°C facilitates the oxidation of oxides in the body. Holding at this temperature for one hour facilitates the expulsion of gases from the repaired body. Rapid cooling after one hour of holding is then performed. Rapid cooling enhances the gloss of the glaze attached to the repaired body and reduces wind cracking.

[0013] In addition, the choice of raw materials will also affect the firing of the blank. Kaolin and clay provide plasticity, which is conducive to drying without cracking after repair. Quartz can stabilize the firing temperature of the repaired blank, thereby reducing the width of the repaired crack. Adding wollastonite and talc during the firing of the blank can promote the melting of quartz and reduce the firing temperature of the repaired area of ​​the blank. The main chemical components of kyanite and the blank are silicon oxide and aluminum oxide, and the two have similar compositions. During the high-temperature firing process, the blank is prone to volume expansion. Adding kyanite can reduce the defects of cracking and high-temperature deformation of the blank during firing, and reduce the probability of concave and convex defects in the blank after firing.

[0014] The adoption of the above technical solution helps to overcome the problems in the prior art of small crack range of the repaired green body, low firing temperature and easy generation of concave and convex defects during firing.

[0015] Furthermore, the average particle size of the refractory wool is 0.4-1.25 mm.

[0016] Adding refractory wool to the prefabricated slurry will fully fill the voids in the green body during firing, which can improve the strength and toughness of the product. At the same time, it can make the high-temperature shrinkage rate of the repaired area similar to that of the green body to be repaired, reducing the risk of cracking in the repaired area due to the difference in shrinkage rate between the two at high temperatures. In addition, the average particle size of the refractory wool also has a certain impact on the repaired green body. When the average particle size of the refractory wool is greater than 1.25mm, white spots are likely to appear on the green body after firing. When the average particle size of the refractory wool is less than 0.4mm, cracking defects are likely to appear in the repaired area. Selecting an average particle size of 0.4-1.25mm and adding it to the prefabricated repair slurry will produce better results on the green body after firing.

[0017] Furthermore, the method of drying the repair slurry and then applying it to the damaged area of ​​the green body to be repaired is to dry the repair slurry so that the moisture content of the repair slurry is 15%-25%, and then after kneading and aging, the repair slurry is applied to the damaged area of ​​the green body to be repaired until it is flush with the surface of the damaged area of ​​the green body to be repaired.

[0018] Furthermore, the colorant includes 1-3 parts by weight of zirconium vanadium yellow colorant, 0.2-2 parts by weight of zirconium iron red colorant, and 0.02-2 parts by weight of cobalt black colorant.

[0019] The addition of pigments can reduce the color difference of the repaired body and make the color of the repaired area close to that of the body after firing.

[0020] The application of the blank repair method provided by the present invention to blank repair can repair blanks with crack widths in the range of 0-15 mm.

[0021] The technical solution of the present invention has the following advantages:

[0022] 1. The method for repairing a blank provided by the present invention adopts a staged firing method, wherein the temperature is first slowly raised to 500-600°C. The heating time is long, which exhausts free water and bound water and promotes quartz crystal transformation, reduces blank shrinkage, and prevents blank deformation or cracking; then the temperature is raised to 1100-1315°C at a slower rate, which is conducive to sufficient oxidation reaction of oxides in the blank; after keeping the temperature for 1 hour, the temperature is quickly lowered. Rapid cooling is conducive to improving the gloss of the glaze attached to the surface of the repaired blank, while reducing the phenomenon of wind cracking of the repaired blank.

[0023] 2. In the method for repairing the blank provided by the present invention, adding refractory wool to the prefabricated slurry can improve the strength and toughness of the product, and at the same time make the high-temperature shrinkage rate of the repair area similar to that of the blank to be repaired, thereby reducing the risk of cracking at the repaired area due to the difference in shrinkage rates between the two at high temperatures.

[0024] 3. The method for repairing the blank provided by the present invention is simple in process and adopts raw materials such as kyanite powder, zirconium vanadium yellow material, zirconium iron red material, and cobalt black material to prepare the repair slurry, which reduces the defects of cracking and high-temperature deformation of the blank, and at the same time makes the repair area close in color to the blank to be repaired, reduces color difference, and makes the product more beautiful.

[0025] 4. The repair method provided by the present invention is applied to the repair of blanks, which can expand the range of the repaired blank cracks and prevent the blanks with crack widths within the range of 0-15 mm from cracking. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 This is the firing temperature curve of the stepwise temperature increase firing method used in the present invention.

[0028] Figure 2 This is a photo of the appearance of the body to be repaired.

[0029] Figure 3 This is a photograph of the appearance of an area to be repaired after the repair slurry provided by the present invention is applied to the area.

[0030] Figure 4 This is a rendering of the repaired structure using the method of Example 1 of the present invention. DETAILED DESCRIPTION

[0031] The following examples are provided for a better understanding of the present invention and are not intended to limit the best mode of implementation. They do not limit the content and scope of protection of the present invention. Any product identical or similar to the present invention obtained by anyone under the guidance of the present invention or by combining the features of the present invention with other prior arts shall fall within the scope of protection of the present invention.

[0032] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in this field can be used. If the manufacturer of the reagents or instruments is not specified, they are all commercially available conventional reagents.

[0033] Example 1

[0034] S1. Determine the damaged area on the surface of the body to be repaired, clean the damaged area, and remove surface dust and impurities. Weigh 20 parts of kaolin, 14 parts of albite, 0.5 parts of talc, 17 parts of clay, 35 parts of quartz, 2 parts of wollastonite, and 10 parts of kyanite powder as pre-made powder, put the pre-made powder prepared in the above proportion into a ball mill, and add ball mill and water in a ratio of pre-made powder: ball mill: water weight = 1:1.5:0.6. Ball mill the powder until the median particle size is controlled at 6-8μm, then pass through a 60-mesh sieve, and finally stir it evenly with a blender;

[0035] S2. Weigh 10 parts of refractory wool with a particle size of 0.4-1.25 mm and add it to a ball mill. Add water and ball mill in a ratio of refractory wool: ball mill: water (weight ratio = 1:5:10). Mill for 10 minutes and then pass through a 100-mesh sieve. Add the milled and sieved refractory wool to the prefabricated slurry from step S1 and stir evenly. Weigh 1 part of zirconium vanadium yellow material, 0.2 part of ferrozirconium red material, and 1 part of cobalt black material to the prefabricated slurry, stir evenly, and sieve to obtain a repair slurry.

[0036] S3. Dry the repair slurry to a moisture content of 16% and then add it to a clay mill for slurry kneading. After aging for 2 days, apply it to the damaged area of ​​the green body to be repaired. Finally, after glazing, fire the repaired green body at room temperature at a rate of 3.5°C / min to 573°C, then increase the temperature to 1315°C at a rate of 3°C / min, hold the temperature for 1 hour, then rapidly cool to 600°C at a rate of 5.5°C / min after holding the temperature for 1 hour, and finally cool to 50°C over 4 hours.

[0037] Example 2

[0038] S1. Determine the damaged area on the surface of the body to be repaired, clean the damaged area, and remove surface dust and impurities. Weigh 26 parts of kaolin, 10 parts of albite, 0.8 parts of talc, 15 parts of clay, 26 parts of quartz, 1 part of wollastonite, and 11 parts of kyanite powder as pre-made powder, put the pre-made powder prepared in the above proportion into a ball mill, and add ball mill and water in a ratio of pre-made powder: ball mill: water weight = 1:1.5:0.6. Ball mill the powder until the median particle size is controlled at 7-12μm, then pass through a 100-mesh sieve, and finally stir it evenly with a blender;

[0039] S2. Weigh 13 parts of refractory wool with a particle size of 0.4-1.25 mm and add it to a ball mill. Add water and ball mill in a ratio of 1:5:10 (by weight) of refractory wool: ball mill: water. Mill for 10 minutes, then pass through an 80-mesh sieve. Add the milled and sieved refractory wool to the prefabricated slurry from step S1 and stir evenly. Weigh 1.5 parts of zirconium vanadium yellow material, 0.8 parts of zirconium iron red material, and 0.02 parts of cobalt black material to the prefabricated slurry, stir evenly, and sieve to obtain a repair slurry.

[0040] S3. Dry the repair slurry to a moisture content of 18% and then add it to a clay mill for clay kneading. After aging for 3 days, apply it to the damaged area of ​​the green body to be repaired. Finally, after glazing, fire the repaired green body at room temperature at a rate of 5°C / min to 600°C, then increase the temperature to 1280°C at a rate of 3°C / min, hold the temperature for 1 hour, then rapidly cool the temperature to 550°C at a rate of 5.5°C / min after holding the temperature for 1 hour, and finally cool the repaired green body to 60°C over 3 hours.

[0041] Example 3

[0042] S1. Determine the damaged area on the surface of the body to be repaired, clean the damaged area, and remove surface dust and impurities. Weigh 28 parts of kaolin, 30 parts of albite, 2 parts of talc, 19 parts of clay, 20 parts of quartz, 4 parts of wollastonite, and 15 parts of kyanite powder as pre-made powder, put the pre-made powder prepared in the above proportion into a ball mill, and add ball mill and water in a ratio of pre-made powder: ball mill: water by weight = 1:1.5:0.6. Ball mill the powder until the median particle size is controlled at 9-12μm, then pass through an 80-mesh sieve, and finally stir it evenly with a blender;

[0043] S2. Weigh 25 parts of refractory wool with a particle size of 0.4-1.25 mm and add it to a ball mill. Add water and ball mill in a ratio of 1:5:10 (by weight) of refractory wool: ball mill: water. Mill for 10 minutes and then pass through a 100-mesh sieve. Add the milled and sieved refractory wool to the prefabricated slurry from step S1 and stir evenly. Weigh 3 parts of zirconium vanadium yellow material, 1.6 parts of ferrozirconium red material, and 2 parts of cobalt black material to the prefabricated slurry, stir evenly, and sieve to obtain a repair slurry.

[0044] S3. The repair slurry is dried to a moisture content of 22% and then added to a clay mill for slurry kneading. After aging for 2 days, it is applied to the damaged area of ​​the green body to be repaired. Finally, after glazing, the repaired green body is fired at room temperature at a rate of 4.5°C / min to 524°C, then heated to 1100°C at a rate of 2°C / min, held at that temperature for 1 hour, then rapidly cooled to 506°C at a rate of 6°C / min after holding for 1 hour, and finally cooled to 53°C over 3.5 hours.

[0045] Example 4

[0046] S1. Determine the damaged area on the surface of the body to be repaired, clean the damaged area, and remove surface dust and impurities. Weigh 31 parts of kaolin, 22 parts of albite, 0.9 parts of talc, 25 parts of clay, 24 parts of quartz, 2.6 parts of wollastonite, and 13 parts of kyanite powder as pre-made powder, put the pre-made powder prepared in the above proportion into a ball mill, and add ball mill and water in a ratio of pre-made powder: ball mill: water weight = 1:1.5:0.6. Ball mill the powder until the median particle size is controlled at 6-10μm, then pass through a 60-mesh sieve, and finally stir it evenly with a blender;

[0047] S2. Weigh 16 parts of refractory wool with a particle size of 0.4-1.25 mm and add it to a ball mill. Add water and ball mill in a ratio of 1:5:10 (by weight) of refractory wool: ball mill: water. Mill for 10 minutes and then pass through a 100-mesh sieve. Add the milled and sieved refractory wool to the prefabricated slurry from step S1 and stir evenly. Weigh 3 parts of zirconium vanadium yellow material, 0.8 parts of ferrozirconium red material, and 1.2 parts of cobalt black material to the prefabricated slurry, stir evenly, and sieve to obtain a repair slurry.

[0048] S3. Dry the repair slurry to a moisture content of 20% and then add it to a clay mill for slurry kneading. After aging for 2 days, apply it to the damaged area of ​​the green body to be repaired. Finally, after glazing, the repaired green body is fired at room temperature at a rate of 5°C / min to 585°C, then heated to 1300°C at a rate of 2.5°C / min, held at that temperature for 1 hour, then rapidly cooled to 524°C at a rate of 5.5°C / min after holding for 1 hour, and finally cooled to 50°C over 4 hours.

[0049] Comparative Example 1

[0050] Comparative Example 1 is a comparative test example of Example 1. The difference from Example 1 is that after glazing, Comparative Example 1 adopts the following firing method: directly firing to 1315°C at a rate of 3.5°C / min at room temperature, then keeping warm for 1 hour, and then quickly cooling to 600°C at a rate of 5.5°C / min after keeping warm for 1 hour, and finally cooling to 50°C after 4 hours to fire the repaired body.

[0051] Comparative Example 2

[0052] Comparative Example 2 is a comparative test example of Example 1. The difference from Example 1 is that after glazing, Comparative Example 1 is fired to 573°C at a rate of 3.5°C / min at room temperature, then heated to 1315°C at a rate of 3°C / min and kept warm for 1 hour. After keeping warm for 1 hour, the repaired body is naturally cooled to 50°C at room temperature.

[0053] Comparative Example 3

[0054] Comparative Example 3 is a comparative test example of Example 1, and the difference from Example 1 is that no kyanite powder is added when preparing the prefabricated slurry.

[0055] Comparative Example 4

[0056] Comparative Example 3 is a comparative test example of Example 1, and the difference from Example 1 is that the particle size of the refractory wool is 0.25 mm.

[0057] Comparative Example 5

[0058] Comparative Example 3 is a comparative test example of Example 1, and the difference from Example 1 is that the particle size of the refractory wool is 2 mm.

[0059] Comparative Example 6

[0060] Comparative Example 6 is a comparative test example of Example 1, and the difference from Example 1 is that no refractory wool is added when preparing the repair slurry.

[0061] Examples 1-4 and Comparative Examples 1-5 were tested, and the test judgments were as follows: 1. Judgment of the width of the repaired crack: After repairing, glazing, and firing ceramic semi-finished products of different crack widths with the repair slurry, observe whether the repaired area is cracked. 2. Judgment of the color difference of the repaired part: For Examples 1-4 and Comparative Examples 1-6, mark the repaired area when glazing, and then measure the whiteness of the repaired area and the non-repaired area after glazing and firing with a whiteness meter to calculate the deviation δ, δ = (whiteness of the repaired area - whiteness of the non-repaired area) / whiteness of the non-repaired area. 3. Drying qualification rate: Take 100 samples with a crack width of 15 mm, repair them with the repair slurry, and place them in a ventilated place to dry naturally after repair. Observe the samples. If cracks, pits, or collapses appear in the repaired area, it is judged as unqualified, otherwise it is judged as qualified. 4. Determination of repair pass rate: Take 100 samples with a crack width of 15mm and repair them with repair slurry. After the repair, place them in a ventilated place to dry naturally. Observe the samples. If cracks, pits, or collapses appear in the repaired area, they are judged as unqualified. Otherwise, they are qualified. Glaze and fire the qualified dried samples. After firing, if cracks, pits, or collapses appear in the repaired area, and the glaze surface of the repaired area is obviously yellow (with a visible color difference from other parts), it is judged as unqualified. Otherwise, it is qualified. Repair pass rate = number of qualified samples fired / total number of samples.

[0062] The test results are shown in Table 1 below:

[0063] Table 1

[0064]

[0065] It can be seen from the test results in Table 1 that when the ceramic body is repaired by a method for repairing a body provided by the present invention in Examples 1-4, the repair is easy to operate, the body does not crack, and after firing, there are no concave-convex defects on the surface of the repaired area, and the glaze is glossy. By setting up Comparative Examples 1-2, it can be demonstrated that the use of a segmented firing method is beneficial to reducing the generation of concave-convex defects and cracks on the surface of the body repair area. Comparative Example 3 can demonstrate that the addition of kyanite powder reduces the probability of concave-convex defects after the body is fired. Comparative Examples 4-6 can demonstrate that the addition of refractory wool and the control of the particle size range of refractory wool also have a certain effect on the repaired area: adding refractory wool to the prefabricated slurry can improve the strength and toughness of the product, and at the same time make the high-temperature shrinkage rate of the repaired area similar to that of the body to be repaired, reducing the risk of cracking at the repaired area due to the difference in shrinkage rate between the two at high temperatures. When the average particle size of the refractory wool is greater than 1.25mm, white spots are likely to appear on the fired green body. When the average particle size of the refractory wool is less than 0.4mm, cracking defects are likely to appear in the repaired area. Selecting an average particle size of 0.4-1.25mm and adding it to the prefabricated repair slurry will produce better results on the fired green body.

[0066] In summary, the method for repairing a blank provided by the present invention uses a staged firing method. The temperature is first slowly raised to 500-600°C. The long heating time expels free water and bound water, promotes quartz crystal transformation, reduces blank shrinkage, and prevents blank deformation or cracking. The temperature is then raised to 1100-1315°C at a slower rate, which is conducive to the full oxidation reaction of oxides in the blank. After holding the temperature for 1 hour, the temperature is rapidly lowered. Rapid cooling is beneficial to improving the gloss of the glaze attached to the surface of the repaired blank and reducing the phenomenon of wind cracking in the repaired blank.

[0067] The repair slurry is prepared with raw materials such as kyanite powder, refractory wool, zirconium vanadium yellow material, zirconium iron red material, and cobalt black material to reduce the defects of cracking and high-temperature deformation of the blank. At the same time, the color of the repair area is close to that of the blank to be repaired, reducing color difference and making the product more beautiful.

[0068] By applying the repair method provided by the present invention to blank repair, the range of blank crack repair can be expanded, and blanks with crack widths within the range of 0-15 mm will not crack.

[0069] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for repairing a blank, characterized in that: include: S1. Clean the damaged area of ​​the green body to be repaired and weigh 20-35 parts of kaolin, 10-30 parts of albite, 0.5-2 parts of talc, 15-25 parts of clay, 20-35 parts of quartz, 1-4 parts of wollastonite, and 10-15 parts of kyanite powder as pre-made powders, and ball mill them in a ratio of pre-made powder: ball mill: water by weight = 1:1.5:0.

6. The median diameter of the pre-made powders is ball milled to 6-12 μm, and then passed through a 60-100 mesh sieve to obtain a pre-made slurry; S2, weighing 10-25 parts by weight of refractory cotton, ball milling and sieving, and then adding it to the prefabricated slurry, the average particle size of the refractory cotton being 0.4-1.25 mm; and adding colorant, stirring evenly, and sieving to obtain a repair slurry, the process of ball milling and sieving is to add refractory cotton, water and ball mill in a ratio of refractory cotton: ball mill: water = 1:5:10 by weight, ball milling for 5-10 minutes, and passing through a 60-100 mesh sieve; S3. After drying the repair slurry, apply it to the damaged area of ​​the green body to be repaired. After glazing, use the staged firing method to fire it to 1100-1315°C to obtain a repaired green body. The specific steps of the staged firing method to fire it to 1100-1315°C are: firing it to 500-600°C at a rate of 3-5°C / min at room temperature, then heating it to 1100-1315°C at a rate of 2-3°C / min and keeping it warm for 1h. After keeping it warm for 1h, quickly cool it to 500-600°C at a rate of 5-6°C / min, and finally cool it to 50-70°C over 3-4h.

2. The method for repairing a blank according to claim 1, characterized in that: The method of drying the repair slurry and then applying it to the damaged area of ​​the green body to be repaired is to dry the repair slurry so that the moisture content of the repair slurry is 15%-25%, and then after kneading and aging, the repair slurry is brushed until it is flush with the surface of the damaged area of ​​the green body to be repaired.

3. The method for repairing a blank according to claim 1, characterized in that: The colorant comprises 1-3 parts by weight of zirconium vanadium yellow colorant, 0.2-2 parts by weight of ferro zirconium red colorant, and 0.02-2 parts by weight of cobalt black colorant.

4. A method for repairing a blank according to any one of claims 1 to 3, characterized in that: The repair method is applied to repair cracks in a blank, and the width of the cracks in the blank is within the range of 0-15 mm.

Images