With the development of science and technology, the requirement for the surface properties of materials is getting higher and higher. In recent decades, the rise of various vapor deposition technologies has made rapid progress in the research and application of surface engineering technology. These technologies not only meet the requirements of mechanical properties, such as wear resistance, friction reduction and corrosion resistance, but also play an important role in the field of surface-related functional materials such as electromagnetics, optics, optoelectronics, thermology, superconductivity and biology. Surface engineering not only makes low-cost metal materials play a greater advantage in performance and efficiency, but also has become an important means of developing new coatings and thin film materials, with great application potential.
With the improvement of the level of mechanical processing industry, new requirements are put forward for cutting tools. In addition to improving service life, it is also required to reduce pollution during cutting and to use dry cutting as far as possible. When cutting fluid can not be completely eliminated, try to make it contain only anti-rust agent and no organic matter, so that the cost of recycling can be greatly reduced.
The diversity of cutting tools and the characteristics of working conditions in use determine the difference in choosing the coating of Jiangsu cutting tools. Different from turning and drilling, milling cutters should consider the characteristics of intermittent impact. In the early stage, wear resistance was the main focus of coatings, and hardness was the main index. Titanium nitride as a representative of this kind of coating has a high friction coefficient (0.4-0.6). Constant friction between the workpiece and the processing will produce a lot of heat energy.
"Cutting fluids are usually used to avoid tool overheating and deformation affecting machining accuracy and prolong service life." Luo Baihui, consultant of Amway Lubrication Technology Brand, said that in order to solve the problem of reducing or eliminating cutting fluid, the tool coating should not only make the tool have a long life, but also have the function of self-lubrication. Diamond-like carbon coatings (DLC) have shown advantages in the mechanical processing of some materials (Al, Ti and their composites). However, after many years of research, it has been shown that the high internal stress, poor thermal stability and catalytic effect between the diamond-like carbon coatings and ferrous metals make the structure of SP3 change to SP2, which determines that it can only be used at present. It has been applied to the processing of non-ferrous metals, which limits its further application in machining. However, recent studies have shown that the hardness of diamond-like coatings (also known as graphite-like coatings) with SP2 structure can also reach 20-40 GPa, but there is no problem of catalytic effect with ferrous metals. The friction coefficient is very low and the wet resistance is very good. Coolant can also be used in dry cutting when cutting, and its life is longer than that of non-ferrous metals. The coated knife has been doubled and there is no problem in processing iron and steel materials, which has aroused great interest of coated companies and tool manufacturers. Over time, this new type of diamond-like coating will be widely used in cutting field.