Structure and Feature of Silicon Nitride Ceramic Blade

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Ceramic blade is made from fine ceramics at the high pressure and known as “the noble knife”. As the product of modern high-tech, it has incomparable advantages than traditional metal tool. Since ceramic blade uses high-tech nanometer zirconia as raw material, it is also called “Zircon knife”. This shows that ceramic blade is elegant and luxurious.

Ceramic blade in the market is mostly processed by a nanomaterial called zirconium oxide. Firstly place zirconium oxide powder into the mould to press into cutter blank at high temperature of 2000°C and high pressure of 300t, and then use diamonds to polish and add a handle. Thus ceramic blade is finished.

Traditional ceramic material generally takes from the nature. Taking soil of Jingdezhen for example, it can be made into all kinds of commodities by manufacturing process such as mixing, shaping and calcining. However, modern high-tech ceramic, also called special ceramic, is made from synthetic material. For instance, silicon nitride powder has high purity. With the modern powder metallurgy, products possess high hardness and high temperature resistance.

Material can be divided into metal material and non-metal material. Non-metal material can be divided into inorganic material and organic material.

No matter what kind of material, its internal microstructure (combination mode and binding force of internal particles) determines its properties such as melting point, hardness and electrical conductivity. Because of weaker molecule binding force, organic material has low melting point and hardness. Metal material is formed from metallic bond. Binding force of metallic bond is stronger than that of molecular bond but weaker than that of covalent bond and ionic bond, so melting point and hardness is still not high. Metal ceramic has certain metallic properties. And it can be made by using metallic oxide (aluminium oxide) or metallic carbide (titanium carbide) as main constituent, adding moderate metal powder (nickel powder, iron powder, etc.) and processing by powder metallurgy. With high strength and abrasive resistance, cemented carbide is the sintered material which combined refractory metallic carbide as principle component with metals as binding phase. Its properties are between metal and ceramic. Ceramic material mainly consists of ionic bond and covalent bond. Its binding force is relatively strong electrostatic attraction between the positive and negative ions or sharing electron pair, so it has high melting point and hardness as well as fine insulativity, chemical stability and oxidability. That is the reason why ceramic material can become a cutting tool.

Features:

a. Good abrasion resistance. Ceramic blade can process high hard materials that traditional cutting tool is difficult to work or unable to work, hence it can avoid wasting electricity resulting of annealing processing and it can also improve the hardness of work pieces and  prolong working life of machines.

b. Not only can achieve the rough and finish machining of hard material, but also can achieve processing with a great impact such as milling, planning and interrupted cutting.

c. Ceramic blade generates small friction force when it works. Since its cutting is not easy to glue on the blade and to produce built-up edge, surface roughness of work pieces is low in the same conditions.

d. Tool life is several times even dozens of times higher than that of traditional tools, which reduce tool change during the process and guarantee work pieces in small taper and high precision.

e. High temperature resistant and good red hardness. Ceramic blade can achieve continuous cutting at a temperature of 1200°C, so its cutting speed is much quicker than that of cemented carbide. High-speed cutting can be performed, and its efficiency is 3-10 times higher than that of traditional tools so that it can save time, electricity and machine tools about 30%-70% or more.

f. Nitrogen and silicon are rich in the nature, and they are principle raw materials of silicon nitride ceramic. Instead of cemented carbide, silicon nitride ceramic can save a large number of crucial metals such as W, Co, Ta and Nb.