Porcelain making process, ceramic making process

1. The water content of the adobe is about 8 to 18 percent, because the water content is too little, the plasticity is weak, and it is mostly loose and moist powder granules or wet hard soil blocks, which must be formed by using strong mechanical pressure and steel molding. Its advantages are: mechanical automatic operation and fast production, neat and uniform steel mold forming, less water content of the blank, so the drying shrinkage is small, and the deformation opportunity is also less.

Its disadvantage is: it can only manufacture a simple shape, and it is most suitable for making various surface bricks.

2. The water content of the embryonic soil is about 25% to 35%: it is the best water content of the embryonic soil to show plasticity, so all kinds of methods of using plasticity to form belong to it. Such as:

1) Pinch plastic billet method: the ancient billet method, only with bare hands and simple tools, modern ceramic works have many adopters, 2) soil strip billet method: one of the ancient embryo making methods. Large-scale utensils, such as water tanks, are made using this method. There are many adopters of modern ceramic works.

3) Roller Blank Method: Roller is also known as pottery car, ancient name is even, for a rotatable disc, take the adobe disc **, both hands are very skillful inside and outside pushing, that is, can make round utensils, such as bowls, bottles and cans. It is the main production method of ancient ceramics in China.

Nowadays, with the advancement of machinery, semi-automatic and fully automatic bowl carts have been made with gypsum molds, which save manpower and product standards, and are the main methods for making round tableware.

4) Model support method: In ancient China, clay was used to make a model, and the clay was first made into a clay piece, which was pressed into the mold and then taken out, and the parts were bonded and trimmed, such as Tang Sancai figurines and pottery horses, etc., were made by this method.

3. The water content of the adobe is about 40% to 55 percent: the excess water content of the adobe has become paste, and an appropriate amount of electrolyte must be added to dilute it, so as to obtain good fluidity, and it is not easy to settle, like dilute molasses-like mud. Gypsum mold casting slurry method:

The plaster model is precise and absorbent. The mud is poured into the gypsum mold, the gypsum mold sucks in water, and the small particles of the suspended adobe in the mud are gradually and evenly piled up on the inner wall of the gypsum mold, and when the adobe is piled up thick enough, the mud that still has fluidity in the first part is poured out, and a body can be obtained on the inner wall of the gypsum mold. Dolls and other dolls are often made using this method.

After the billet is formed, it needs to go through the process of trimming and drying, and the shrinkage phenomenon of the clay after drying, and the shrinkage phenomenon that will also occur during firing, which are the main reasons for the deformation and rupture of the clay.

Glazing method. Glaze is the appearance of ceramics, and the success or failure of this ceramic is often controlled. The glaze must be properly matched with the green body, such as the expansion coefficient of the blank glaze, the firing temperature, etc. Glaze is classified according to its contents, including lead glaze, boron glaze, feldspar glaze, lime glaze, ash glaze, salt glaze, etc.

Yin Shang first made gray glaze. Han, Tang Sancai is a low-temperature lead glaze, and the glaze color is varied and gorgeous. Song Duo uses feldspar glaze, the glaze is warm and moist, which makes people have an unfathomable sense of profundity. In the Qing Dynasty, it was made of lime glaze, which was clear and exquisite. Make the underglaze blue and white clearer.

How porcelain is made

After mining, beneficiation, crushing, washing, stale and other processes, porcelain stone is made into a white brick-like substance near Jingdezhen, which is directly used to make porcelain tires, named Buzi, pronounced Dunzi. This material Jingdezhen Qingbai porcelain in the Song Dynasty was directly used to make porcelain, and at the end of the Yuan Dynasty, Jingdezhen potters began to add a kind of macang clay containing kaolin to the porcelain, forming a binary formula for porcelain.

At present, there is a great controversy in the academic community about whether it belongs to porcelain stone minerals or kaolin minerals. Due to historical documents, in the late Ming Dynasty and the middle of Wanli, the macang soil had been excavated and replaced with kaolin.

Therefore, it is generally believed that the composition of macang soil should be relatively close to that of kaolin. Since the asakura soil has been completely extinct, the composition of the asakura soil has become an unsolved case to this day. You just need to know that from the end of the Yuan Dynasty to the tenth year of Wanli in the Ming Dynasty, the official kilns in Jingdezhen used Macang soil.

The ceramic making process is as follows:

1.Mud training: Porcelain stone is taken from the mining area, which is manually crushed with an iron hammer to an egg-sized block, and then beaten into powder with water, washed, removed impurities, and precipitated into brick-like mud.

Then mix the mud with water, remove the slag, and rub it with both hands to squeeze out the air in the mud. This porcelain stone processing method has a long history and should be synchronized with the history of porcelain making in Jingdezhen.

2.Blank drawing: Blank drawing is the first process of molding. Jingdezhen porcelain.

Famous all over the world, except for the local "godsend."

In addition to the high-quality clay, it is basically those "magical" skills that turn these ordinary "things" into human "pets". First of all, we must be familiar with the shrinkage rate of the mud.

3.Blank: The shape of the impression is rotated according to the shape arc of the blank, and the blank that is dried until it is semi-dry is covered on the mold, and the outer wall of the blank is evenly patted, and then the mold is removed.

4.Billet: Cover the billet on the wheel.

On the sharp barrel of the car, turn the car disc and rotate it with a knife to make the thickness of the green body appropriate and the surface and inside smooth, which is a process with high technical requirements.

This process is first to put the yellow mud on the so-called billet car, and then sit on the car, with special tools to make the surface of the utensils smooth, coherent and consistent, and make the mud show a white color, which is an extremely important process in ceramic molding, and finally determine the shape of the utensils.

5.Drying blanks: Place the processed blanks on a wooden frame to dry.

6.Engraving: Carving patterns on dried bodies with knives made of bamboo, bone or iron.

7.Glazing: The glazing process is the technology of ancient ceramics production.

One is to apply glaze paste to the surface of the molded ceramic body. There are mainly seven methods such as dipping glaze, swinging glaze, pouring glaze, brushing glaze, sprinkling glaze, wheel glaze, etc., according to the different shapes and thicknesses of the body, the corresponding glazing method is adopted. Since the Yuan Dynasty, Chinese porcelain.

The history of painted decoration.

8.Kiln: First of all, the ceramic products are loaded into the sagger, the role of the box is to prevent the porcelain blank from direct contact with the kiln fire, to avoid pollution, especially for the white porcelain firing is the most beneficial.

The kiln firing time process is about one day and night, and the temperature is about 1300 degrees. First build the kiln door, light the kiln, the fuel is pine firewood, the Tsubaki technical guidance, measure the fire, grasp the kiln temperature changes, and decide the ceasefire time.

9.Paint: Overglaze.

Such as five-color, pastel, etc., is to paint patterns and fill in the color on the glazed surface of porcelain that has been fired, and then enter the red furnace to burn and dry at a low temperature of about 700-800 degrees. Before firing the kiln, painting on the blank voxel tire, such as blue and white, glaze red, etc., is called underglaze color.

It is characterized by the fact that the color is under the glaze at high temperature and never fades.

The ceramic process is as follows:

1. Mud training. Porcelain stone is taken from the mining area, first manually crushed with an iron hammer to an egg-sized block, and then beaten into powder with water, washed, removed impurities, and precipitated into brick-like mud.

Then mix the mud with water, remove the slag, rub it with your hands, or step on it with your feet, squeeze out the air in the mud, and make the moisture in the mud even.

2. Blank drawing. Throw the mud ball in the center of the turntable of the roller car, and pull out the general appearance of the body with the flexion and extension of the hand. Blank drawing is the first process of molding. First of all, we must be familiar with the shrinkage rate of the mud.

3. Printing blank. The shape of the impression is rotated according to the inner shape arc of the blank, and the blank that is dried until it is semi-dry is covered on the mold, and the outer wall of the blank is evenly patted, and then the mold is removed.

4. Billet. The billet is covered on the sharp barrel of the roller car, the car disc is rotated, and the knife is rotated to make the thickness of the billet body appropriate, and the surface and the inside are smooth, which is a process with high technical requirements. The billet, also known as the "repair billet" or "rotary billet", is the key link to finally determine the shape of the utensil, and make the surface of the utensil smooth, coherent and consistent.

Internal and external repair is an extremely important molding technology in Jingdezhen porcelain-making process and superior to other kiln systems, and it is a unique technical guarantee for the formation of Jingdezhen ceramic style.

5. Drying blanks. The processed billet is placed on a wooden frame to dry.

6. Engraving. Bamboo, bone, or iron knives are used to carve patterns on the dried body.

7. Glazing. Ordinary round ware is glazed or glazed. Blowing glaze for cutters or large round ware. Most ceramic products need to be glazed before they can be fired in the kiln. The glazing process may seem simple, but it is an extremely important and difficult process to master.

It is not easy to achieve the uniform glaze layer of each part of the green body, the appropriate thickness and the different fluidity of various glazes.

8. Firing kiln. First of all, the ceramic products are loaded into the sagger, which is a container for the baking of ceramic products, made of refractory materials, and the function is to prevent the porcelain blank from being in direct contact with the kiln fire and avoid pollution, especially for the most beneficial to white porcelain firing.

9. Painting. The glaze color such as five-colored, pastel, etc., is to depict the pattern and fill the color on the glazed surface of the porcelain that has been fired, and then enter the red furnace to burn and bake at a low temperature, with a temperature of about 700-800 degrees.

The specific steps are as follows:

1. Knead the mud, and use the method of kneading the horn to make the mud dry and wet and uneven fully kneaded.

2. When there is air in the mud, rubbing it with chrysanthemums can squeeze the bubbles.

3. Pull the blank, throw the mud ball on the center of the turntable on the wheel, and pull out the general appearance of the body with the flexion and extension of the hand.

4. Blank, cover the blank on the bucket of the roller car, rotate the car plate, and rotate it with a knife to make the thickness of the blank body appropriate and the surface and inside smooth.

5. The billet, also known as the repair billet or rotary billet, is the key link to finally determine the shape of the utensil, and make the surface of the utensil smooth, coherent and consistent.

6. Dry the blank, and place the processed blank on the wooden frame to dry.

7, glazing, most of the ceramic products need to be glazed before entering the kiln firing, glazing process seems simple but is extremely important and difficult to master a process, to achieve the glaze layer of each part of the body is uniform, the thickness is appropriate, but also pay attention to the different fluidity of various glazes.

8. The last part is the kiln.

The production process of porcelain generally requires the following processes: clay refining, embryo making, glazing, kiln firing, and painting.

The refining of porcelain generally requires porcelain stone, quartz stone or mullite as raw materials, while glaze is a slurry made of feldspar, quartz, talc, aged clay and certain raw materials mixed together and ground in a certain proportion. The glaze is then applied to the surface of the embryo body, and various chemical reactions are undergoing by heating at high temperatures, and finally porcelain is formed.

Practicing mud is to use high territory, porcelain stone, which has plasticity and good viscosity of clay, to grind and wash, remove impurities and knead evenly, and slowly blend into porcelain clay for making porcelain. The clay will be used as a porcelain tire in the future.

For example, if you want a bowl, then pinch it into the shape of a bowl, shape it into the shape of a vase, and dry it to a semi-dry state after the clay embryo is made, and then put it on the embryo drawing machine to collect the embryo surface through the knife, so as to ensure that the appearance of the porcelain is smooth and clean, and finally use a carving knife of different materials to carve the required pattern on the model according to the needs.

Glazed glaze in porcelain is divided into glaze color, underglaze color and glaze color, generally underglaze color we can see in household porcelain and blue and white porcelain, in fact, a layer of pigment is applied to the porcelain tire before glazing, there is glaze protection and isolation, so that the color of the pigment can be preserved for a long time, and it will not wear and fade for a long time. But precisely because the pigment is under the glaze, the color does not look bright.

The glaze color is to first glaze the porcelain fetus, then put it into the kiln, and then color it after firing, and then put it into the low-temperature kiln after the color is finished, and sinter it again. This practice is mainly to ensure that the pattern and color of the glaze are bright, but because the pigment is on the outside of the glaze, it is easy to fade, and if it is exposed to the sun for a long time, the surface of the porcelain will be seriously worn and the color will fall off.

Glaze color, in fact, and the glaze color method is almost the same, after the last layer of pigment is painted, and then a layer of glaze is applied on the outside, so that the porcelain is not only bright and not easy to fade, which is the blue and white porcelain inside is considered to be superior.

The kiln fills the porcelain bottle into the sagger, which is actually equivalent to the oven in which we bake bread and eat, and this sagger is the container for porcelain baking, the main function is to resist high temperature, isolate the porcelain from direct contact with fire, and avoid the porcelain being polluted during the firing process, especially when the white porcelain is broken, it is extremely easy to get ash. Generally, the kiln takes one night, and the temperature is always maintained at about 1300 degrees.

Painting is to paint on the glazed surface of the porcelain that has been fired, fill the porcelain with some patterns, and then put the porcelain into the red furnace to bake at a low temperature, and the temperature is kept between 700 and 800 degrees. After the final step of painting, the entire magnet is completed.

Porcelain is one of the traditional crafts in China, with a long history and unique craftsmanship. The following is the process of making porcelain, including raw material preparation, molding, drying, firing, decoration, glazing and other steps.

Preparation of raw materials. The raw materials of porcelain mainly include porcelain clay, quartz sand, feldspar, etc. These ingredients need to be screened, blended, and pulverized to ensure quality and purity. In the process of mixing, the texture and color of the porcelain clay need to be adjusted according to different proportions and recipes.

Molding. Molding is the first step in porcelain making, mainly by hand or by machine to make the porcelain clay into the desired shape and size. Common molding methods include hand-drawn blanks, roulette molding, mold molding, etc.

In the process of molding, it is necessary to grasp the humidity or stove, pressure and speed of the porcelain clay to ensure the quality and efficiency of molding.

Dry. Once formed, porcelain needs to be dried to remove moisture and volatile substances while enhancing its hardness and stability. The time and method of drying vary depending on the size and shape of the porcelain, and it is usually necessary to carry out the drying in an environment with the right temperature and humidity to avoid excessive drying or excessive humidity.

Fired. Firing is the core step of porcelain production, and it is also the most complex and critical link. The firing process needs to be divided into three stages: the front kiln, the middle kiln and the back kiln, and the temperature and atmosphere of each stage are different.

The temperature of the former kiln is lower, which is used to remove moisture and volatile substances from the porcelain body; The temperature of the middle kiln gradually increases, which is used to sinter the porcelain body and form porcelain; The temperature is highest in the back kiln, which is used to melt the glaze and create a shiny surface.

Ornament. The decoration of porcelain is usually divided into two ways: hand-painted and printed. Hand painting involves the use of tools such as paints and brushes to draw various patterns and words onto the surface of the porcelain.

Printing requires the use of a printing machine or printing plate, and the pre-designed patterns and text are printed on the surface of the porcelain. The content and manner of decoration can be chosen according to the purpose and style of the porcelain.

Glaze treatment. The surface of the porcelain after firing usually needs to be glazed to enhance its luster and abrasion resistance. The glaze can be transparent or tinted, depending on the color and style of the porcelain.

The glaze can be treated by spraying or dipping, and it is necessary to grasp the uniformity and thickness of the coating.

Through the above steps, a variety of exquisite porcelain can be made, such as bowls, plates, pots, bottles, etc. The production of porcelain requires patience, skill and experience, as well as constant practice and summarization in order to produce high-quality and unique pieces.