The reason why the non-ferrous metal solution produce flames when placed into the injection chamber in die casting process is mainly due to the oxidation-reduction reaction of the metal at high temperature, which releases energy and forms bright light and heat. ‌

When the metal solution is placed in the injection chamber and heated at high temperature, the electrons in the metal atoms absorb energy and jump from the low energy orbit to the high energy orbit. However, the electrons in the high energy orbit are unstable and will quickly jump back to the low energy orbit, releasing excess energy. This energy is released in the form of light, forming a specific spectrum, thus producing flames.

Color effects of different metal solutions in flames

Different metals will produce different color effects in flames. For example:

· ‌Sodium salt‌: After adding sodium salt (such as sodium chloride), the flame will appear bright yellow, because sodium ions react with hydrogen at high temperature to release yellow sodium light.

· ‌Potassium salt‌: After adding potassium salt (such as potassium chloride), the flame will appear purple, because potassium ions are excited at high temperature and emit purple light.

· ‌Copper salt‌: After adding copper salt (such as copper sulfate), the flame will appear green, because copper ions decompose at high temperature and release green light.

Principle of flame color reaction

The principle of flame color reaction is based on the energy level transition of metal ions in an excited state. When metal salts are added to the flame, their molecules or ions are heated to a high temperature and are in an excited state. In the excited state, metal ions absorb energy from the flame and electrons transition to a higher energy level. When electrons return to a lower energy level, energy is released, which is emitted in the form of light to form a specific spectrum.