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Structural Ceramics Using High Purity

Hangzhou JWG Technology Co.Ltd | Updated: Aug 17, 2017

   Advanced ceramics usually refers to the use of high purity, ultra-fine synthetic or selected inorganic compounds as raw materials, with accurate chemical composition, precision manufacturing and processing technology and structural design, and has excellent characteristics of the ceramic. Advanced ceramics can be classified into high-strength, high hardness, high temperature, corrosion resistance and oxidation resistance. They are functional ceramics with electrical properties, magnetic properties, biological characteristics, heat sensitivity and optical characteristics. Advanced ceramics are widely used in high temperature, corrosion, electronics, optics, as a new material, with its excellent performance in the field of materials is unique, by the people attach great importance to the future society will play an important role.

First, structural ceramics

Structural ceramics are: cutting tools, molds, wear parts, pumps and valve components, engine parts, heat exchangers and armor. The main materials are silicon nitride (Si3N4), silicon carbide (SiC), zirconium dioxide (ZrO2), boron carbide (B4C), titanium diboride (TiB2), alumina (A12O3) and Sialon.

(1) Si3N4 based ceramic material

C fiber reinforced Si3N4-based ceramic materials, with ZrO2 phase effect to prevent the fiber and the matrix due to the thermal expansion coefficient of the mismatch caused by the crack, the composite fracture toughness increased by 5 times. Silicon nitride ceramics with its excellent overall performance and rich resources to become a high-performance ceramic applications in the potential of a cutting tool, each year about 140 tons of silicon nitride powder for tool manufacturing, worth about 300 million US dollars.

(2) silicon carbide-based ceramics

The silicon carbide ceramics prepared by the hot pressing process have a density close to the theoretical density, and the bending strength can reach 500 to 600 MPa even at a high temperature of about 1400 ° C. The C fiber reinforced SiC composites prepared by CVI method have a strength of 520MPa and a fracture toughness of 16.5MPa · m. The addition of 25 vol% TiB silicon carbide composite ceramics, if the strict control of the initial particle size, can make the strength of 888MPa, breaking strength of 8.8MPa · m. It can be said that silicon carbide is a high-temperature air in the high strength of the material, the thermal conductivity after the beryllium oxide ceramic material. China has a lot of enterprises to produce silicon carbide powder, which is a large part of the export, but mainly low-taste for the manufacture of refractory brick with silicon carbide powder. Eastern Europe has 150,000 tons / year of production capacity, North America's production capacity of 100,000 tons / year. High purity, high activity of silicon carbide powder is very high price of 14-40 dollars / kg, the annual demand of about 15 million US dollars, the powder used in the manufacture of high-performance silicon carbide ceramics.

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Hangzhou JWG Technology Co.Ltd