A. Basic principle of discharge
1.The electrodes are close to the workpiece surface, the workpiece surface generates high pressure on each other, and the electrolyte begins to ionize into a plasma energy column.
2.After the energy column is formed, the electrode transmits a low voltage to the workpiece surface.
3.When electrons flow between the electrodes, they generate extremely high thermal energy, resulting in an electrochemical reaction that creates bubbles of hydrogen gas.
4.During the discharge, the material under the energy column is in a molten state.
5.At rest, the hydrogen bubble implodes, and this part processes the liquid for gasification.The melted material is cooled, solidified and released through the surrounding treatment fluid.
At the end of the discharge cycle, a cavity is formed on the workpiece due to the removal of the material.This is the smallest unit in EDM, followed by the next discharge cycle.
B, processing characteristics
1.Large electrode or rough machining efficiency is significant
2.The advantages of small electrodes or finishing are not obvious
3.The electrical parameters are completely different from those of copper electrodes
4.The sheet electrode does not deform during discharge
5.Sensitive to current easily cause abnormal discharge
6.The low losses are due to carbon bonding
7.Surface roughness is not up to the high standard of copper electrode