Preparation method and application of binary formula Dai pottery clay

Abstract

The invention relates to a preparation method and application of a binary formula Dai pottery pug. The preparation method comprises the following steps: taking Dai pottery clay in the HongRiver basin, Wuhua soil in the HongRiver county and charcoal dust, and exposing and weathering the Dai pottery clay and the Wuhua soil for at least three months; the mass content of SiO2 in the Dai clay in the HongRiver basin is not less than 50%, the mass content of Al2O3 is not less than 15%, the mass content of Fe2O3 is not less than 10%, and the ignition loss is less than 10%; the content of SiO2 in the Wuhua soil in the Honghe county is 72%-82%, the content of Al2O3 is 9%-12%, and the content of Fe2O3 is 3%-5%; the preparation method comprises the following steps: adding water into the Dai pottery clay and the Wuhua soil according to the mass ratio of the Dai pottery clay to the Wuhua soil to the charcoal powder of (100-120): (40-50): (8-10), fully soaking, then carrying out ball milling, sieving slurry, then adding the charcoal powder, uniformly stirring, squeezing mud, draining, pugging and exhausting. According to the invention, the throwing and compression molding performances of the Dai pottery clay can be improved, the sintering temperature and the compactness and strength of the structure of the Dai pottery clay can be improved, and the burn out rate can be reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of ceramic clay formula and pottery preparation process, and specifically relates to an improvement of the clay formula of Dai pottery in the Red River Basin of Yunnan Province, my country, and a method for preparing Dai pottery using the clay. Background Art

[0002] For thousands of years, Dai ethnic groups in the Red River Basin, Xishuangbanna, Dehong and other places in my country have widely used Dai pottery as their main living utensils. They all use local Dai pottery clay and slow wheel pottery making techniques. The production techniques are similar. They all use low-temperature clay that is easily available locally. Through simple drying, crushing, adding water and mixing into mud, mud flakes are used as the base, and clay strips are used to make pottery. The Dai pottery clay process used in traditional Dai pottery is a one-unit formula, that is, only one type of clay collected locally (such as Figure 1 As shown in the figure, residents of Honghe County collect traditional clay for pottery making. Occasionally, some fine sand (about 30%) is added to increase the hardness of pottery, which can reduce the proportion of cracking during firing. Due to the limitations of raw material properties, the clay is very sticky, and it is not easy to operate by throwing or pressing molds, and it is easy to stick to hands and molds. The firing temperature of the traditional flat ground pile firing method is relatively low, usually about 600-800℃, and it is easy to crack and the yield rate is low. Even if advanced modern liquefied gas kilns are used, the temperature is difficult to exceed 1100 degrees. Due to the low firing temperature, the sintering degree of the product is small, and it is easy to absorb various dust and oil stains. In addition, after adding sand during the blank making, leakage will occur, which is not strong, the strength of the utensils is low, the structure is loose, and slight collisions during use are also easy to scratch and damage. At present, the Dai slow wheel pottery making process in Yuanyang, Honghe, Yuanjiang, Xinping and other counties in the Red River Basin is still the same, and the products produced are relatively rough and fragile.

[0003] In recent years, Dai pottery clay has begun to be produced on a large scale using modern machinery, that is, weathered clay is ball-milled, filtered, squeezed, and kneaded to obtain finished clay. Such clay has finer particles and better viscosity, and the product firing temperature can be increased to 1050°C, but it is still difficult to operate during throwing or pressing, and it is easy to stick to hands and molds. In addition, the shrinkage ratio increases, resulting in a 30% increase in the proportion of product cracking during the firing process. The fired product structure is still relatively loose and has a low density. It is easy to crack when heated to high temperatures during use, and the service life is short, which makes it difficult to meet people's living needs. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and provide a method for improving the process performance of low-temperature Dai pottery clay using a binary formula, so as to improve the throwing and pressing properties of Dai pottery clay, increase the sintering temperature and the density and strength of its organization, and reduce the burning rate.

[0005] The technical solution adopted by the present invention is as follows: A method for preparing a binary formula Dai pottery clay material, the method is as follows: (1) Take Dai pottery clay from the Red River Basin, Wuhua soil from Honghe County, and charcoal powder, and expose the Dai pottery clay and Wuhua soil to the sun and weather for at least three months for use; the Dai pottery clay from the Red River Basin has a SiO2 mass content of not less than 50%, an Al2O3 mass content of not less than 15%, a Fe2O3 mass content of not less than 10%, a mass content of other metals of less than 1%, and a loss on ignition of less than 10%; the Wuhua soil from Honghe County is a mixture of yellow, red, white, purple, and cyan, with a SiO2 content of 72-82%, an Al2O3 content of 9-12%, and a Fe2O3 content of 3-5%; the charcoal powder has a mesh size of 150-170; (2) Weigh the raw materials in a mass ratio of 100-120:40-50:8-10 for Dai pottery clay: Wuhua soil: charcoal powder, put the Dai pottery clay and Wuhua soil into a ball mill, soak them in water, and then ball mill them. Pass the mud through a 150-170 mesh sieve and put it into a slurry pool. Then add charcoal powder into the slurry pool, stir evenly, squeeze the mud to drain the water, and then knead the mud to expel the air to obtain the binary formula Dai pottery mud material, which is aged for later use.

[0006] The invention can make blanks after the binary formula Dai pottery clay material is aged and then air-dried; the air-dried clay blanks are then placed in a furnace and fired at 1250-1270° C. in an oxidizing atmosphere to obtain reddish-brown Dai pottery finished products.

[0007] The present invention can also make blanks after the binary formula Dai pottery clay material is aged, and then air-dried; then the air-dried clay blanks are placed in a furnace and fired at 1240-1260° C. in a reducing atmosphere to obtain gray-black Dai pottery finished products.

[0008] The present invention has the following significant effects: (1) The present invention improves the traditional Dai pottery clay mono-formula into a binary clay formula of Dai pottery clay and Wuhua soil in a reasonable ratio. In the formula, the Dai pottery clay in the Red River Basin has a low silicon and aluminum content, resulting in low refractoriness, and has strong plasticity, strong viscosity, and high organic matter content, which makes it difficult to throw and press molds, and has a large burning loss. The present invention can significantly reduce the viscosity of Dai pottery clay and improve its plasticity by adding Wuhua soil containing high silicon, aluminum, iron and low impurities, making it easy to throw and press molds and not easy to stick to hands and molds. More importantly, due to the reasonable increase in the SiO2 content, the refractoriness of the clay has been significantly improved by utilizing the characteristics of SiO2, such as small thermal expansion coefficient, small volume change during rapid cooling and heating, and small thermal stress generated. The clay can be fired at high temperatures without easily cracking, and the product yield rate has been significantly improved. The product has a dense structure and high strength, is not easy to crack or be damaged during use, and the surface is not easily scratched.

[0009] (2) Traditional Dai pottery clay is made into mud by simply beating, sieving and adding water without ball milling. The particle size is large, the product structure is loose, and it has certain thermal explosion resistance. Although the mud after ball milling has finer particles, it can improve the structural density of the fired product and the strength of the finished product, but the shrinkage ratio of the mud is also increased, which will cause cracking during the firing process and increase the scrap rate. The present invention can reduce the elastic modulus of the mud, reduce the stress during firing, and appropriately increase the porosity by adding an appropriate amount of charcoal powder and strictly controlling the particle size of the charcoal powder, thereby improving the thermal shock resistance. In addition, the added charcoal powder can also shorten the firing time. In a reducing atmosphere, it is easier to change the valence state of the iron element in the blank to obtain finished products of different colors.

[0010] (3) After the clay material of the present invention is formed into a blank, the firing temperature can be as high as 1240-1270°C. The fired product has high strength, good high temperature resistance, is not easy to absorb impurities, and has stable performance. It can overcome the defects of traditional Dai pottery products such as loose structure, easy leakage and easy cracking.

[0011] (4) The Dai pottery products fired by the method of the present invention have a high yield rate and the scrap rate can be reduced to less than 5%, which is significantly lower than the scrap rate of traditional Dai pottery of up to 25%. The qualified finished products have good thermal shock resistance and will not crack even when cooking food or boiling water at high temperature for a long time.

[0012] (5) The finished product obtained by firing the present invention has almost the same color mechanism as the traditional Dai pottery products, but has a more delicate appearance, uniform color, and no cracks, perfectly retaining the characteristics of Dai pottery products.

[0013] (6) The raw materials of the present invention are all collected locally, are easy to mine, have a stable supply, low production cost, and have strong market competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 To collect the traditional clay used to make Dai pottery; Figure 2 These are photos of traditional Dai pottery products; Figure 3 The photos of the cross-section structure of traditional Dai pottery products; Figure 4 This is a photo of the finished Dai pottery fired in an oxidizing atmosphere in Example 1; Figure 5 A photograph of a pottery fragment section of the finished Dai pottery product of Example 1; Figure 6 This is a photo of the finished Dai pottery fired in a reducing atmosphere in Example 3; Figure 7 A photograph of a cross section of a finished Dai pottery product of Example 3; Figure 8 This is a photo of the soil from the Wuhua soil mine in Langdi Township, Honghe County. DETAILED DESCRIPTION

[0015] The content of the present invention is further described below in conjunction with embodiments. Example 1

[0016] The method of using a binary formula to improve the process performance of low-temperature Dai pottery clay is as follows: (1) Take Dai pottery clay from the Red River Basin, Wuhua soil from Honghe County, and charcoal powder, and expose the Dai pottery clay and Wuhua soil to the sun and weather for three months for use. The Dai pottery clay from the Red River Basin used in this embodiment, after sampling and testing, has a SiO2 mass content of 55%, an Al2O3 mass content of 18%, a Fe2O3 mass content of 11%, a calcium oxide, a magnesium oxide, and a titanium oxide mass content of 1%, and other metal contents of less than 0.1%. The loss on ignition (also known as loss on ignition, which is the rate of mass reduction after high-temperature firing) is about 9%. The Wuhua soil in Honghe County is a natural ore Wuhua soil with abundant reserves collected from Langdi Township, Honghe County, Yunnan Province. It is a mixture of yellow, red, white, purple, and cyan. Figure 8 , with the characteristics of high silicon, low aluminum, low iron, low viscosity and high refractoriness. The Wuhua soil used in this embodiment has a SiO2 content of 81%, an Al2O3 content of 11%, a Fe2O3 content of 4%, and other metal contents of less than 0.1%, and a loss on ignition of about 4%. The charcoal powder is purchased from the market or prepared by itself, and the mesh size of the charcoal powder is 160 mesh; (2) Weigh 100 parts of Dai clay, 40 parts of Wuhua soil, and 8 parts of charcoal powder according to their mass, put the Dai clay and Wuhua soil into a ball mill, soak them in water for two hours, and then ball mill them for three hours. The mud is passed through a 160-mesh sieve and put into a slurry pool. Then, charcoal powder is added to the slurry pool. After stirring evenly, the mud is squeezed to drain the water, and then the mud is kneaded to expel air to obtain a finished mud. The finished mud is aged for later use. (3) Use the stale finished mud to make blanks and then dry them; (4) The dried clay is placed in a furnace and fired at 1250°C in an oxidizing atmosphere to obtain a reddish-brown Dai pottery product. Figure 3 .compared to Figure 2 The traditional Dai pottery products shown have a more delicate appearance, uniform color and no cracks. Figure 5 The ceramic fragment section of the product of this embodiment is shown. Figure 3 The cross section of traditional Dai pottery products ( Figure 3 The product structure of this embodiment is more uniform and dense. Example 2

[0017] The method of using a binary formula to improve the process performance of low-temperature Dai pottery clay is as follows: (1) Take Dai pottery clay from the Red River Basin, Wuhua soil from Honghe County, and charcoal powder, and expose the Dai pottery clay and Wuhua soil to the sun and weather for three months for use. The Dai pottery clay from the Red River Basin was sampled and tested, and its SiO2 mass content was 56%, Al2O3 mass content was 17%, Fe2O3 mass content was 12%, calcium oxide, magnesium oxide and titanium oxide mass content were close to 1%, and other metal content was less than 0.1%. The loss on ignition was about 8.8%. The Wuhua soil from Honghe County was sampled and tested, and its SiO2 content was 78%, Al2O3 content was 10%, Fe2O3 content was 5%, and other metal content was less than 0.1%. The loss on ignition was about 3.5%. The mesh size of the charcoal powder is 170 mesh; (2) Weigh 100 parts of Dai clay, 50 parts of Wuhua soil, and 9 parts of charcoal powder according to their mass, put the Dai clay and Wuhua soil into a ball mill, soak them in water for two hours, and then ball mill them for 3.5 hours. The mud is passed through a 170-mesh sieve and put into a slurry pool. Then, charcoal powder is added to the slurry pool. After stirring evenly, the mud is squeezed to drain the water, and then the mud is kneaded to expel air to obtain a finished mud. The finished mud is aged for later use. (3) Use the stale finished mud to make blanks and then dry them; (4) Place the dried clay in a furnace and fire it at 1270°C in an oxidizing atmosphere to obtain a reddish-brown Dai pottery product. Example 3

[0018] The method of using a binary formula to improve the process performance of low-temperature Dai pottery clay is as follows: (1) Take Dai pottery clay from the Red River Basin, Wuhua soil from Honghe County, and charcoal powder, and expose the Dai pottery clay and Wuhua soil to the sun for four months for use. Dai pottery clay and Wuhua soil are the same as in Example 1. The mesh size of the charcoal powder is 150 mesh; (2) Weigh 100 parts of Dai clay, 40 parts of Wuhua soil, and 8 parts of charcoal powder according to their mass, put the Dai clay and Wuhua soil into a ball mill, soak them in water for about 2 hours, and then ball mill them for about 3 hours. The mud is passed through a 150-mesh sieve and put into a slurry pool. Then, charcoal powder is added to the slurry pool. After stirring evenly, the mud is squeezed to drain the water, and then the mud is kneaded to expel air to obtain a finished mud. The finished mud is aged for later use. (3) Use the stale finished mud to make blanks and then dry them; (4) Place the dried clay in a furnace and fire it at 1240°C in a reducing atmosphere to obtain a gray-black Dai pottery product. Figure 6 . The cross-sectional structure of the product is shown in Figure 7 At fracture B on the middle right, the product structure is also uniform and dense, and its appearance is more delicate than traditional Dai pottery products, with uniform color and no cracks. Example 4

[0019] The method of using a binary formula to improve the process performance of low-temperature Dai pottery clay is as follows: (1) Take Dai pottery clay from the Red River Basin, Wuhua soil from Honghe County, and charcoal powder, and expose the Dai pottery clay and Wuhua soil to the sun and weather for at least three months for use. The Dai pottery clay from the Red River Basin was sampled and tested, and its SiO2 mass content was 51%, Al2O3 mass content was 16%, Fe2O3 mass content was 12%, calcium oxide, magnesium oxide and titanium oxide mass content was about 1%, other metal content was less than 0.1%, and the loss on ignition was about 9.8%. The Wuhua soil in Honghe County was sampled and tested, and its SiO2 content was 82%, Al2O3 content was 10%, Fe2O3 content was 3%, other metal content was less than 0.1%, and the loss on ignition was about 4%. The mesh size of the charcoal powder is 160 mesh; (2) Weigh 120 parts of Dai clay, 45 parts of Wuhua soil, and 10 parts of charcoal powder according to their mass, put the Dai clay and Wuhua soil into a ball mill, soak them in water, and then ball mill for about 3 hours. The mud is passed through a 160-mesh sieve and put into a slurry pool. Then, charcoal powder is added to the slurry pool. After stirring evenly, the mud is squeezed to drain the water, and then the mud is kneaded to expel air to obtain a finished mud. The finished mud is aged for later use. (3) Use the stale finished mud to make blanks and then dry them; (4) Place the dried clay in a furnace and fire it at 1260°C in a reducing atmosphere to obtain a gray-black Dai pottery product. Example 5

[0020] The method of using a binary formula to improve the process performance of low-temperature Dai pottery clay is as follows: (1) Take Dai pottery clay from the Red River Basin, Wuhua soil from Honghe County, and charcoal powder, and expose the Dai pottery clay and Wuhua soil to the sun and weather for at least three months for use. The Dai pottery clay from the Red River Basin was sampled and tested, and its SiO2 mass content was 53%, Al2O3 mass content was 17%, Fe2O3 mass content was 11%, the mass content of calcium oxide, magnesium oxide and titanium oxide was about 0.9%, the content of other metals was less than 0.1%, and the loss on ignition was about 10%. The Wuhua soil in Honghe County was sampled and tested, and its SiO2 content was close to 82%, Al2O3 content was 9%, Fe2O3 content was 4%, the content of other metals was less than 0.1%, and the loss on ignition was about 4%. The mesh size of the charcoal powder is 160 mesh; (2) Weigh 110 parts of Dai clay, 45 parts of Wuhua soil, and 9 parts of charcoal powder according to their mass, put the Dai clay and Wuhua soil into a ball mill, soak them in water, and then ball mill for about 4 hours. The mud is passed through a 160-mesh sieve and put into a slurry pool. Then, charcoal powder is added to the slurry pool. After stirring evenly, the mud is squeezed to drain the water, and then the mud is kneaded to expel air to obtain a finished mud. The finished mud is aged for later use. (3) Use the stale finished mud to make blanks and then dry them; (4) Place the dried clay in a furnace and fire it at 1250°C in a reducing atmosphere to obtain a gray-black Dai pottery product.

[0021] The above embodiments are only some embodiments of the present invention, not all embodiments, and are not intended to limit the protection scope of the present invention. Those skilled in the art should understand that any data adjustment and replacement of equivalent technical means within the scope of the claims of the present invention should fall within the protection scope of the present invention.

[0022] In the method of the present invention, the ball milling, mud squeezing and drainage, mud kneading and air removal, finished mud aging, blank making, drying, firing in an oxidizing atmosphere (commonly known as oxidation firing), and firing in a reducing atmosphere (commonly known as reduction firing) are all existing technical means and will not be described in detail here.

[0023] Unless otherwise specified, the percentages described in the present invention are all mass ratios, and the parts described in the present invention are all mass parts.

Claims

1. A method for preparing a binary formula Dai pottery clay material, characterized in that: Here’s how: (1) Take Dai pottery clay from the Red River Basin, Wuhua soil from Honghe County, and charcoal powder, and expose the Dai pottery clay and Wuhua soil to the sun and weather for at least three months for use; the Dai pottery clay from the Red River Basin has a SiO2 mass content of not less than 50%, an Al2O3 mass content of not less than 15%, a Fe2O3 mass content of not less than 10%, a mass content of other metals of less than 1%, and a loss on ignition of less than 10%; the Wuhua soil from Honghe County is a mixture of yellow, red, white, purple, and cyan clay, with a SiO2 content of 72-82%, an Al2O3 content of 9-12%, and a Fe2O3 content of 3-5%; the charcoal powder has a mesh size of 150-170; (2) Weigh the raw materials in a mass ratio of 100-120:40-50:8-10 for Dai pottery clay: Wuhua soil: charcoal powder, put the Dai pottery clay and Wuhua soil into a ball mill, soak them in water, and then ball mill them. Pass the slurry through a 150-170 mesh sieve and put it into a slurry pool. Then add charcoal powder into the slurry pool, stir evenly, squeeze the mud to drain the water, and then knead the mud to expel the air to obtain the binary formula Dai pottery mud material, which is aged for later use.

2. The application of the binary formula Dai pottery clay prepared by the method of claim 1, characterized in that: The binary formula Dai pottery clay material is aged and then formed into blanks, which are then air-dried; the air-dried clay blanks are then placed in a furnace and fired at 1250-1270° C. in an oxidizing atmosphere to obtain reddish-brown Dai pottery products.

3. The application of the binary formula Dai pottery clay prepared by the method of claim 1, characterized in that: The binary formula Dai pottery clay material is aged and then formed into blanks, which are then air-dried; the air-dried clay blanks are then placed in a furnace and fired at 1240-1260° C. in a reducing atmosphere to obtain gray-black Dai pottery products.

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