The dimensional accuracy and shape and position accuracy of cemented carbide drawing die are achieved by grinding. Because the grinding force of cemented carbide is 2-3 times that of general steel. Therefore, the grinding machine is required to have high power and high rigidity. As far as my country's current machine tool level is concerned, there is no special grinding machine for processing cemented carbide. Therefore, machining errors are often caused, and the cumulative effect of the errors will seriously damage the service life of the drawing die. In the EDM process, because the drawing die material is subjected to high temperature up to about 10000C and the action of the liquid medium at the moment of discharge, the surface layer will undergo changes in the metallographic structure, and there may be carburization (carbon in the working fluid) and carburization. Metal (copper tungsten electrode), and even the appearance of micro cracks, will undoubtedly affect the life. The insert is to make the alloy can withstand greater impact and extrusion load. Whether it is hot-pressed inserts or cold-pressed inserts, the clearance requirements are very strict. Generally, the interference of 0.03-0.05mm is selected for cold-pressed inserts, 0.08-0.10mm for hot-pressed inserts, 700-800C for cavity sleeve heating, and about 300C for cemented carbide. After the hot pressing is completed, put it in a 600C box furnace to keep the temperature Zh in order to eliminate stress. The welding of cemented carbide is also a key technology, and brazing is generally used more
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