⑴ Types of ceramic tool materials

The types of ceramic tool materials can generally be divided into three categories: alumina-based ceramics, silicon nitride-based ceramics, and composite silicon nitride-alumina-based ceramics. Among them, alumina-based and silicon nitride-based ceramic tool materials are the most widely used. The performance of silicon nitride-based ceramics is superior to that of alumina-based ceramics.

⑵ Performance and characteristics of ceramic cutting tools

The performance characteristics of ceramic cutting tools are as follows:

① High hardness and good wear resistance: Although the hardness of ceramic cutting tools is not as high as PCD and PCBN, it is much higher than that of carbide and high-speed steel cutting tools, reaching 93-95HRA. Ceramic cutting tools can process high-hard materials that are difficult to process with traditional cutting tools and are suitable for high-speed cutting and hard cutting.

② High temperature resistance and good heat resistance: Ceramic cutting tools can still cut at temperatures above 1200°C. Ceramic cutting tools have good high-temperature mechanical properties. A12O3 ceramic cutting tools have particularly good oxidation resistance. Even if the cutting edge is in a red-hot state, it can be used continuously. Therefore, ceramic tools can achieve dry cutting, thus eliminating the need for cutting fluid.

③ Good chemical stability: Ceramic cutting tools are not easy to bond with metal, and are corrosion-resistant and have good chemical stability, which can reduce the bonding wear of cutting tools.

④ Low friction coefficient: The affinity between ceramic tools and metal is small, and the friction coefficient is low, which can reduce cutting force and cutting temperature.

⑶ Ceramic knives have applications

Ceramics are one of the tool materials mainly used for high-speed finishing and semi-finishing. Ceramic cutting tools are suitable for cutting various cast irons (grey cast iron, ductile iron, malleable cast iron, chilled cast iron, high alloy wear-resistant cast iron) and steel materials (carbon structural steel, alloy structural steel, high strength steel, high manganese steel, quenched steel etc.), can also be used to cut copper alloys, graphite, engineering plastics and composite materials.

The material properties of ceramic cutting tools have the problems of low bending strength and poor impact toughness, making them unsuitable for cutting at low speeds and under impact loads.