1. EDM external threads of cemented carbide are easy to cause micro-cracks and chipping.

        EDM is to use the heat generated by instantaneous discharge to melt, vaporize, lift, and throw raw materials to produce production and processing chips. The discharge energy and the energy in the whole process of discharge are the primary elements for the removal of raw materials. Compared with ordinary raw materials, the raw materials have high strength and high melting point. Large discharge electric energy must be selected in the whole process of EDM. In addition, the thermal conductivity of cemented carbide is small, so it is likely to produce higher than ordinary metal materials on the surface. temperature field to achieve the thermal stress yield limit. Thermal stress manifests itself as plastic deformation and the release of cracks. During EDM machining of cemented carbide, once the thermal stress exceeds the yield limit, cracks and even chipping will appear on the surface of the product workpiece.

      In order to prevent the formation of micro-cracks, the discharge amount should be controlled. The key to the discharge energy is the higher value current amount and pulse width. In the case of a constant peak current, the pulse width expands and the discharge energy increases, but the raw material sludge load decreases.

       2. EDM external thread easy boring machine

        During EDM, the melted and vaporized production and processing chips produce fine particles residues in the electrode holes according to the refrigeration material, which cannot be successfully discharged to produce deposits, which are very easy to cause short-circuit failures, resulting in boring machines, which is not conducive to subsequent production and processing. . In addition, the residue will continue to cause secondary discharge, jeopardizing the machining accuracy. Therefore, it is necessary to completely improve the traditional electric stage design scheme, create a safe channel for liquid fluidity inside and outside, and make the milling surface smooth.

       3. Electric discharge machining of cemented carbide external thread is more serious

       In the production process, in order to better reduce the loss of the electrode and improve the processing accuracy, metal electrodes with high melting point are usually selected. If the standard is limited, copper electrodes for general steel plate processing can also be used.