At present, the commonly used methods to prepare aluminum nitride powder include direct nitridation of aluminum powder, carbothermal reduction of aluminum oxide, sol method, self propagating combustion method, plasma synthesis method, decomposition method of polymer containing ALN bond, chemical vapor deposition method, water initiated solid phase reaction method, sol gel method, etc. Below, the editor will introduce the commonly used synthesis methods for aluminum nitride powder.
1) Aluminum powder direct nitriding method
ALN+N2 → 2ALN Put the aluminum powder into a reaction furnace filled with nitrogen and ammonia, and heat it to 600 ℃ to start the reaction. This is a simple and straightforward method that can synthesize a large amount of high-purity ALN powder without any side reactions. It has been widely produced.
However, this method is generally difficult to obtain aluminum nitride powder with fine and uniform particles, and usually requires post-treatment. The formation of an ALN layer on the surface of AL particles after nitriding will hinder the diffusion of nitrogen towards the center of the particles, so the conversion rate using this method is also an important issue.
2) Carbon thermal reduction method of alumina
The method of Al203+3C+N2 → 2AlN+3CO is currently widely used in industrial production, and its research is relatively in-depth.
In the preparation of aluminum nitride powder in this method, calcium oxide, calcium fluoride, yttrium oxide, etc. are often added as catalysts. Among them, adding calcium fluoride is more effective in reducing activation energy and improving reaction rate. The aluminum nitride powder prepared by this method has high purity, good formability and sintering performance, but high synthesis temperature, long reaction time, and larger powder particle size.
The above is the commonly used synthesis method for aluminum nitride powder that we have introduced to you. We hope it can be helpful to you. If you want to learn more about aluminum nitride, please feel free to continue with us.