Ceramic cutting tool
Ceramic tool has the characteristics of high hardness, good wear resistance, good heat resistance and chemical stability, and is not easy to bond with metal. Ceramic cutting tools play a very important role in CNC machining. Ceramic cutting tools have become one of the main cutting tools for high speed cutting and difficult to process materials. Ceramic cutting tools are widely used in high speed cutting, dry cutting, hard cutting and difficult to process materials. Ceramic cutting tools can efficiently process the high hard materials that traditional cutting tools can't process at all, so as to realize "using car instead of grinding". The optimum cutting speed of ceramic tool can be 2 ~ 10 times higher than that of cemented carbide tool, thus greatly improving the production efficiency of machining; The main raw materials used in ceramic cutting tool materials are the most abundant elements in the earth's crust. Therefore, the popularization and application of ceramic cutting tools is of great significance to improve productivity, reduce processing costs, and save strategic precious metals. It will also greatly promote the progress of cutting technology.
1.Type of ceramic tool materials
Ceramic cutting tool materials generally can be divided into three categories: alumina - based ceramics, silicon nitride - based ceramics, composite silicon nitride - alumina - based ceramics. Alumina - based and silicon nitride - based ceramic tool materials are the most widely used. The performance of si3n4 - based ceramics is superior to that of alumina - based ceramics.
2.Ceramic tool performance, characteristics
(1) High hardness, good wear resistance: although the hardness of ceramic tools is not as high as PCD and PCBN, but much higher than the carbide and high-speed steel tools, up to 93-95hra.Ceramic tools can be used to process hard materials which are difficult to be processed by traditional tools, and are suitable for high speed cutting and hard cutting.
(2) High temperature resistance, good heat resistance: ceramic tool in 1200℃ above the high temperature can still be cut. Ceramic cutting tools have good high temperature mechanical properties, A12O3 ceramic cutting tools have particularly good antioxidant properties, cutting edge even in the red heat state, but also continuous use. Therefore, ceramic cutting tools can achieve dry cutting, thus eliminating cutting fluid.
(3) Good chemical stability: ceramic tool is not easy to bond with metal, and corrosion resistance, good chemical stability, can reduce the tool bonding wear.
(4) Low friction coefficient: ceramic tool and metal affinity is small, low friction coefficient, can reduce the cutting force and cutting temperature.
3. Application of ceramic cutting tools
Ceramic is one of the tool materials mainly used for high - speed finishing and semi - finishing. Ceramic tool is suitable for cutting all kinds of cast iron (gray cast iron, ductile cast iron, malleable cast iron, cold cast iron, high alloy wear resistant cast iron) and steel (carbon structural steel, alloy structural steel, high strength steel, high manganese steel, quenched steel, etc.), also can be used for cutting copper alloy, graphite, engineering plastics and composite materials.
The ceramic cutting tool has the problems of low bending strength and poor impact toughness, which are not suitable for cutting under low speed and impact load.