Many processes have been developed for manufacturing Si3N4 powder, including a direct nitration process of silicon powder, a silicon diimide process, a carbothermal reduction and nitration process using SiO2 powder, a gas phase reaction process, a plasma process, and so on. Among them, the direct nitration and diimide methods are known to be commercialized in industries. Direct nitration is based on the direct reaction between metallic Si powder and nitrogen gas at an elevated temperature and the diimide methods, the decomposition of silicon chloride as start material, and the reaction with ammonia gas for nitration. On the other hand, many researchers have suggested that nitration of Si is a more simple and easy process and therefore concentrated on developing the Si powder with high purity. Mainly two processes have been researched to produce the fine metallic silicon powder 1) ball milling of Si scrap and 2) the magnesium reduction from SiO2. Ball milling is known to be a simple process. However, it often has contamination problems for bulk Si to be powdered finely. The magnesium reduction process was also intensively researched because the driving force for reduction is high enough, and the magnesium is vaporized easily even below 1273 K. It was reported that both the gaseous and solid phases of the magnesium had been used as the reductant. However, the gaseous reaction was more actively performed because of cost-up according to the use of solid magnesium powder. If you are looking for high quality, high purity and cost-effective Silicon powder, or if you require the latest price of Silicon powder, please feel free to email contact mis-asia.