Fe–Si Powder Nitriding Control System.

Abstract—To reduce the losses of ferrosilicon during heavy-medium separation, it is necessary to increase its corrosion and mechanical resistance with the obligatory preservation of magnetic properties. To form ferrosilicon powder with the specified physical and mechanical characteristics that meet the technological process requirements, an automated heat treatment process control system is designed. The formed nitrided layer thickness is found to be controlled by the holding time and temperature. The total processing time is 3 h, and the temperature can vary in the range 900–1000°C. At higher temperatures, intense growth of silicon nitride crystals occurs. [ABSTRACT FROM AUTHOR]