Original pottery
In 6,000 to 5,000 BC, China invented the original pottery. The Chinese Shang Dynasty (about 17th century BC ~ about 11th century BC) had original non-metallic materials experimental machine porcelain, and appeared glazed pottery. In the future, in order to meet the needs of court viewing and folk daily use and construction, the production technology of ceramics continues to develop. Celadon in the 200th year of the Eastern Han Dynasty (the Eastern Han Dynasty) is the earliest porcelain discovered so far. The appearance of pottery promoted the entry of mankind into the metal age. The ceramic pottery used for copper smelting in the Xia Dynasty (about 22 BC to the beginning of the 21st century to the beginning of the 17th century BC) was the earliest refractory material. The smelting temperature of iron is much higher than that of copper, so the refractory material of the iron age has correspondingly developed greatly.
Refractory
The rise of the steel industry after the 18th century promoted the development of refractory materials in the direction of multiple varieties, high temperature resistance and corrosion resistance. In 3700 BC, Egypt began to have simple glass beads for decorations. 1000 years ago, China also had white perforated glass beads. In the early Christian era, Rome was able to produce glass products of various shapes. Glass manufacturing technology has matured between 1000 and 1200, and Venice in Italy has become the center of the glass industry. After 1600, the glass industry has spread all over the world. Gas-hardening cementitious materials such as lime and gypsum have been used from 3000 BC to 2000 BC. With the development of the construction industry, the cementitious materials have also been developed accordingly. In the beginning of the first year, there was hydraulic lime and volcanic ash cementitious material. After 1700, it was made of hydraulic lime and Roman cement. In 1824, British J. Asputin invented Portland cement (see cement). The main {HotTag} components of the above ceramics, refractories, glass, cement, etc. are all silicates and are typical silicate materials.
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