High-life and low-pollution machine tools are widely used

With the development of science and technology, the surface properties of materials have become increasingly demanding. The rise of various vapor deposition techniques in recent decades has led to rapid advances in the research and application of surface engineering technology. These technologies not only fulfill the requirements of mechanical properties such as wear resistance, friction reduction, and corrosion resistance, but also demonstrate their capabilities in the field of surface-related functional materials such as electromagnetics, optics, optoelectronics, thermals, superconductivity, and biology.

Surface engineering not only enables inexpensive metal materials to play a greater advantage in terms of performance and efficiency, but also has become an important means for the development of various new coating and thin film materials, and has great potential for application. With the improvement of the level of the machining industry, new requirements have been placed on the tool. In addition to increasing the service life, it is also required to reduce the contamination during cutting and use dry cutting as much as possible. When the cutting fluid cannot be completely eliminated, try to make it contain only anti-rust agent and no organic matter, which can greatly reduce the cost of recycling.

The variety of tool cutting tools and the operating state characteristics of the machine tool determine the choice of tool coating. Different from turning and drilling, milling cutters should also consider the characteristics of intermittent impact. The early development of the coating is mainly focused on wear resistance, in order to increase the hardness as the main indicator. Such coatings represented by titanium nitride have a high coefficient of friction (0.4-0.6), and constant friction between the workpiece and the workpiece will generate a large amount of thermal energy.

In order to avoid tool deformation caused by overheating affecting machining accuracy and extending its service life, cutting fluids are usually used. To solve the problem of reducing or eliminating the cutting fluid, the tool coating should not only allow the tool to have a long life, but also have a self-lubricating function. The appearance of diamond-like coatings (LCs) has shown advantages in the machining of certain materials (Al, Ti, and their composites), but after years of research it has been shown that DLC coatings have high internal stress and poor thermal stability. The three disadvantages of the catalytic effect between the ferrous metal and the SP3 transition to the ferrous metal determine that it can currently only be used to process non-ferrous metals, thus limiting its further application in machining.

However, studies in recent years have shown that the hardness of diamond-like coatings (also called graphite-like coatings) based on SP2 structure can reach 20-40 GPa, but there is no problem of catalytic effect with ferrous metals, and the friction coefficient is very high. Low and good moisture resistance, coolant can also be used for dry cutting, its life is more than double the non-plating knife, there is no problem in the processing of steel materials, resulting in the coating company, tool manufacturers Great interest. In time, this new type of diamond-like coating will be widely used in the field of cutting.