Production process and equipment of spherical silicon powder

Spherical silicon powder production process and equipment

Spherical silica powder refers to an amorphous quartz powder material with spherical particles and silicon dioxide as its main component. Its production raw materials are mainly angular silica powder, and its production methods mainly include flame melting method, plasma heating furnace method, chemical synthesis method, hydrolysis method, etc.

At present, the flame melting method is mainly used in China to produce spherical silicon powder . The key to this technology is that the heating device requires a stable temperature field, easy to adjust the temperature range and no secondary pollution to the silicon powder.

The principle and process of producing spherical silicon micropowder by high-
frequency plasma melting method are similar to those of flame melting method. It mainly transforms the high-temperature heat source into a plasma generator. It has a moderate temperature range, stable control, high output, and can achieve a high spheroidization rate. Therefore, it is a more suitable production method. The hydrolysis method is to add liquid SiCl ₄ to deionized water with different dispersants added at a constant speed, and stir the hydrolyzate at high speed with a quartz rod at the same time. After aging, washing and filtering, the obtained hydrolyzate is dried and dehydrated to constant weight in a constant temperature box at 100℃-200℃, and then transferred to a high-temperature sintering furnace. High-temperature sintering, dehydroxylation and crystal conversion are carried out at different temperatures. After grinding and screening, high-purity spherical silicon micropowder with the required particle size is obtained.
It is understood that the spherical powder production technology includes: (1) the explosion method, which is used to prepare micron-level products; (2) the flame method, which is used to prepare submicron-level products. This method can produce the largest amount of products; (3) the liquid phase method, which is used to produce high-value-added spherical silicon and spherical aluminum liquid phase synthetic products that do not allow large particles and have strict technical indicators. They can be used in M8 and above copper clad laminates.