Kinetic Study of the Ferrosilicon Nitriding Process

The ferrosilicon nitride used for steelmaking has been synthesized by direct nitriding. The relationship between the reaction temperature and nitriding effect was investigated. The results show that the initial reaction temperature between FeSi75 and nitrogen is approximately 900°C. Increasing holding temperature or prolonging holding time is beneficial to increase the nitrogen content in the nitrided product. At 1400°C, the nitrogen content in ferrosilicon nitride reached 30.28% when the holding time was 4 h. With the increase of nitriding reaction temperature, the phase of α-Si3N4 transferred to β-Si3N4 gradually. Pore diffusion was identified as the dominant restrictive link during the ferrosilicon nitriding process.