Improve the precision of mold cutting tools

The development trend of the former machine tool is high speed, high precision and high quality. The high-speed operation requires higher surface treatment requirements for molds, cutting tools, and mechanical parts. Extending the useful life, reducing production costs, and creating higher profits are the common goals pursued by the industry.

The types of ceramic hard films developed with PVD technology are increasing, including titanium nitride, titanium carbonitride, titanium carbide, alumina, diamond-like films, and titanium aluminum nitride. This kind of ceramic hard film is currently applied to tools or molds, not only improving the wear resistance of the tool surface, but also the toughness of the metal substrate. With the recent breakthroughs in machine tool technology, cutting has moved toward higher speeds to shorten the cutting time and improve the surface accuracy of workpieces.

In order to cope with high-speed machining and save a lot of processing time and costs, tool improvement has become an important factor. Tungsten carbide tools have a growing share in the tool market because of their higher wear resistance and hardness. In order to obtain the best benefits in processing, proper surface treatment must be selected. Medium and heavy load molds must be CVD high-temperature titanium plating, supplemented by precision vacuum heat treatment to achieve acceptable deformation. This part is commonly used in cold forging die, hydraulic drawing die, tungsten carbide drawing line, suction pipe. In the application of tools, molds, and mechanical parts with medium or low load or precise requirements, PVD titanium plating at low temperature (150°C to 500°C) is appropriate.

Aluminium titanium nitride with high aluminum content can easily generate aluminum oxide on the surface of the hard film. This layer of oxide film can make titanium aluminum nitride ceramic hard film oxidation temperature reached 923 degrees Celsius, can protect tungsten carbide cutting tool high-speed cutting edge oxidation resistance and maintain high temperature hardness. However, although titanium nitride and titanium carbonitride also form titania oxide films at high temperatures, they are not easily adhered to the hard films and flaking off with chips, which results in a lack of protection of the hard films, rapid oxidation, and deterioration. Therefore, no matter whether the surface treatment of high-temperature or low-temperature coating has to be properly selected, a proper substrate and stable heat treatment must be used, and the pre-treatment of fine-grinding and polishing of the surface must be followed in order to improve.