The development of the mobile phone industry is changing every day. Mobile phones use new materials and new technologies. With the commercialization of 5G communication approaching, mobile phone case materials are also using new materials for signal transmission and meeting needs. the needs of users. Now, the mainstream mobile phone brands have begun to use ceramic or glass materials. Ceramic and glass mobile phone cases have the advantages of not shielding signals, high hardness, wear resistance, beautiful appearance and good hand feeling, and they are given preference. users.
We see and use glass products every day. This common thing is called one of the most important materials for a person. Do you think glass, like plastic, is a new material invented in our time, but not the best? case , Glass is one of the earliest man-made materials invented by mankind, appeared after ceramics and has a history of more than 4000 years.
We are proud that China invented ceramics, paper, gunpowder, etc. We have been leading the world in the invention and use of materials since ancient times, but the development of widely used glass in China is far behind. Why?
The invention of ceramics has a thousand-year history. China is the "hometown of ceramics". Pottery has become an important part of the history of Chinese civilization. Ceramics are used throughout life.
Pottery is a general term for pottery and porcelain. China mastered ceramic technology thousands of years earlier than Europe. The appearance of pottery is a symbol of humanity from the Paleolithic era to the Neolithic era. It is used as essentials. such as containers or utensils, and later, due to the progress of the production process, the scope of use becomes wider and wider.
Using clay or china clay as raw material, the vessel is made by metering, shaping, glazing, firing and other processes. The hardness of ceramic is very high, and its melting point exceeds 2000 ° C. When clay meets water, it can be molded into various shapes, and it can be filled with water when fired up to 800°C. It can be porcelainized when fired up to 1200°C. It can resist high temperature corrosion, wear resistance, non-absorbent, and anti-oxidation. These characteristics are widely used as functional materials in various industries.
Glaze plays an important role in the development of ceramics. Glaze on pottery is a vitreous layer attached to the body of the embryo. Glaze is a raw material synthesized from calcium-containing stones or shell powder and coal ash in ancient times. After grinding, it is turned into a liquid paste state, applied to the surface of the body of the embryo, and fired at high temperature. At high temperature, the glaze becomes a glassy substance and adheres to the body of the embryo. After the temperature of the drop, the glaze forms a vitreous thin layer on the surface of the ceramic. After glazing, the ceramic surface becomes brighter and denser, which can improve strength and water resistance.
Glass is made from various chemicals (raw materials: soda ash, limestone, quartz sand, etc.), because it is a mixture, so there is no fixed melting point, and the melting point starts at 600°C--800°C From solid to liquid state.
The main raw material for glass production is quartz sand, but the melting point of quartz sand is 1700°C. Such a temperature cannot be reached in ancient kilns. By adding soda ash, vegetable ash and quartz stone stabilizer raw materials to the composition of combustible additives, glass can be produced, but at that time, due to the limitation of the production process, the purity of the glass was not high, and there were many bubbles inside.
Glass first appeared in 3500 BC. BC, when it was invented by the Egyptians, who used it to make jewelry and knead it into small glass bottles.
In 1000 BC, the Egyptians mastered the blowing process and were able to blow glass products of various shapes, the scope of glass use became wider.
Commercial glass appeared in the 12th century and began to be used as a building material for doors and windows.
In the 17th century, the Italians added lead to quartz sand to make crystal glass with high transparency and good refractive indices, and this glass also started the development.
For a long time after the invention of glass, it was a very expensive material. At that time, it was as much a luxury as gold and precious stones, and only high-ranking officials could use it. Later, due to the development of manufacturing technology and the growth of world trade, glass and its products are well known all over the world. Modern people can only understand the use of ancient Chinese glass through the excavation of ancient tombs.
During the excavation of the tomb of King Goujian of the Spring and Autumn and Warring States era, two pieces of light blue glass were inlaid on a bronze sword. This kind of glaze becomes translucent glass after cooling. The earliest glass technology in China may have originated from ceramic glazes.
During the Western Han Dynasty, large thin-walled glass vessels appeared, made of the same material as glass, a translucent emerald green color similar to jade, and made by injection molding.
In ancient China, glass was called glass. After the Song Dynasty, the number of different glass vessels began to increase, but they always retained their own color characteristics. The main use is jewelry, ritual vessels, funerary objects, etc., so they are used in a smaller range than pottery.
It was not until the Qing Dynasty that clear glass technology entered China from the West, and factories began to be built to mass-produce glass.
From the invention of glass jewelry in the Spring and Autumn and Warring States periods to the introduction of Western glass technology to China, glass has been in history for thousands of years. Even after the collapse of the Roman Empire, China's materials technology was ahead of the West by 1000. In 1999, he was an expert in many technologies, but glass was not as widely used by people as ceramics. It can be said that China has not made much contribution to glass technology in history. There are several reasons for this:
The function of glass overlaps with the function of ceramics, and the perfect development of ceramics causes the Chinese to lose andinterest in glass.
China is a country that worships jade. The characteristics of ancient glass and jade are the same, so glass was abandoned.
In a feudal society, good technologies and objects were in the hands of princes and nobles, and the scope of use was very small, which did not contribute to the development of glass technology.
So it's not that China didn't invent glass, perhaps because of ceramics and jade, China abandoned the development of glass.
These reasons may have led to the lack of development of glass in China and even influenced the progress of modern science and technology in China. When glass was still a luxury for the royal family, Western countries already used glass to make telescopes, microscopes, laboratory glass tubes, etc., these inventions can greatly promote the development of science and technology, the lack of all of our ancient glass may be one of the reasons in which China's modern science and technology lags behind in some aspects.
However, glass technology in China is now at the forefront of the world. Fuyao glass is used in two out of every three cars in China, and its products account for about 25% of the global market. With the development of technology in my country, modern glass technology already with the rapid development, new records are born, 0.12mm ultra-thin glass is one of them, this size is relative to the thickness of A4 paper, not only ultra-thin, but also very strong, impact force test is comparable to the impact force of a small car. Hitting a wall at a speed of 150 kilometers, this kind of glass is widely used to display electronic products. The appearance of ultra-thin glass not only broke the technological monopoly of foreign countries, but also showed China's strength in glass materials technology.
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