Plasma, also known as the fourth state of matter, is an electromagnetic gas discharge phenomenon that partially ionizes gaseous particles. This ionized gas includes atoms, molecules, atomic groups, ions, and electrons. Plasma means that the polishing agent is water-soluble under high temperature and high pressure. Under high temperature and high pressure, electrons will break away from the nucleus and run out, and the nucleus will form a positively charged ion. When these ions reach a certain amount, they can become plasma. The energy is very large. When these plasmas rub against the object to be polished, the object will achieve a bright surface in an instant.