Synthesis of Si3N4 powder by powder metallurgy method in atmospheric pressure N2: A review

Catalytic effects of metals, which are often involved in the fabrication of silicon nitride product, on the direct nitridation of silicon have been reviewed through this study. A nitridation echancement effect has also been observed with the addition of some metals. The metals are mixed with Si in separate mass ratios before reaction. The results showed that the conversion from Si to Si3N4 increased markedly with increasing content of the catalyst. From there, it helps to reduce the reaction temperature as well as energy costs for the direct nitridation process. Besides, metal catalysts also react with Si to create MexSiy compounds that reduce the high-temperature resistant properties of Si3N4. Therefore, it is necessary to choose appropriate catalysts so that the product retains its preeminent properties.