Why is diamond a good cutting tool?

Among numerous cutting tool materials, diamond stands out as an ideal choice for cutting operations in both industry and daily life. This is mainly attributed to its unique physical and chemical properties, which endow diamond with excellent cutting performance. I. Extremely High Hardness Diamond has the highest hardness among known substances in nature, with a Mohs hardness of 10. This extremely high hardness enables diamond to easily scratch and wear other materials while remaining almost un-worn itself. When used for cutting, diamond can generate sufficient pressure on the surface of the material being cut, causing local fragmentation or plastic deformation, thus achieving the purpose of cutting. In contrast, ordinary cutting tools, such as hacksaw blades, have a much lower hardness than diamond. When cutting materials with relatively high hardness, the saw blade itself will wear out rapidly, resulting in a decrease in cutting efficiency and cutting quality. II. Good Wear Resistance Diamond is not only hard but also has excellent wear resistance. During the cutting process, there is intense friction between the tool and the material being cut, which causes the material on the surface of the tool to gradually wear away. Due to the extremely stable atomic structure of diamond and the strong carbon-carbon bond energy, it can maintain a relatively stable shape and size during long-term friction, greatly extending the service life of the cutting tool. For example, in the stone processing industry, diamond saw blades used to cut marble and other stones have a much longer service life than ordinary saw blades. They can still maintain good cutting performance after continuously cutting a large amount of stone. III. High Thermal Conductivity Diamond has extremely high thermal conductivity, with a thermal conductivity higher than that of many metals. During the cutting process, a large amount of heat is…