Tungsten carbide tools are increasing in the proportion of high-speed machining
February 21, 2023
The number of ceramic hard films developed by PVD technology is increasing, including titanium nitride, titanium carbonitride, titanium carbide, aluminum oxide, diamond-like films, and titanium aluminum nitride. Such ceramic dura mater is currently applied to a tool or a mold, which not only improves the wear resistance of the tool surface, but also does not lose the toughness of the metal substrate. With the recent breakthrough in machine tool technology, cutting has been speeding up to shorten the cutting time and improve the surface precision of the workpiece. “The current trend of machine tools is high speed, high precision and high quality.” Luo Baihui said that the surface treatment requirements for molds, cutting tools and mechanical parts are getting higher and higher in high-speed operation. Extending the service life, reducing production costs, and creating higher profits are the common goals pursued by the industry. In order to cope with high-speed machining and save a lot of processing time and cost, tool improvement has become an important factor. Tungsten carbide tools are increasingly used in the tool market due to their high wear resistance and hardness. Luo Baihui believes that to obtain the best benefits during processing, it is necessary to choose the appropriate surface treatment. Medium and heavy-duty molds need to be CVD high-temperature titanium, supplemented by precision vacuum heat treatment to achieve acceptable deformation. This part is often used for cold forging dies, hydraulic drawing dies, tungsten carbide drawing lines, and suction pipes. In the application of tools, molds and mechanical parts with medium, low load or high precision requirements, it is appropriate to use low temperature (150 ° C ~ 500 ° C) PVD titanium plating. Aluminum nitride having a high aluminum content easily forms alumina on the surface of the hard film. This layer of oxide film can make the aluminum oxide titanium ceramic hard film have an oxidation resistance temperature of 923 degrees Celsius, which can protect the edge of the tungsten carbide tool from high oxidation resistance and maintain high temperature hardness. However, although titanium nitride and titanium carbonitride also form a titanium oxide film at a high temperature, they do not easily adhere to the hard film and peel off with the chips, so that the hard film lacks protection, rapid oxidation, and deterioration. Therefore, regardless of the surface treatment of high-temperature or low-temperature coating, it is necessary to select an appropriate substrate and a stable heat treatment, supplemented by pre-treatment of surface fine grinding and polishing, in order to improve. The processing efficiency of the ultra-high temperature resin bond diamond grinding wheel is lower than that of the METROX grinding wheel. Due to the high bonding strength, short production cycle and low processing cost, the grinding wheel is not easy to cause chipping when grinding the cutting edge of the tool, and can be used according to the use requirements. It has been ground into a variety of shaped grinding wheels, so it is still widely used in production. How to further improve the grinding performance of such grinding wheels has also become an important task at present. With the rapid development of tool design, manufacturing and use technology, and the increasing tool output, the ultra-high temperature resin bond diamond grinding wheel still cannot fully meet the requirements of mass production of tools, and its quantity and quality still have room for further development. . To this end, Shanghai Zhongyu Company is further researching how to improve the grinding performance of this grinding wheel, especially for the wear resistance of the bonding agent, the bonding strength of the bonding agent and the diamond abrasive and the self-sharpness, etc. Great progress has been made. The test results show that the improved grinding wheel grinding efficiency can be increased by about 20% on the original basis, and the grinding wheel life can be increased by about 50%.
