Carbothermic reduction of manganese oxide under various gases in the temperature range of 1273-1573 K in order to understand the formation reaction of manganese carbide is investigated. The experimental results indicate that the formation reaction of manganese carbide depends on the temperature, the CO partial pressure, and the activity of carbon. The reaction rate for Mn7C3 formation is shown to be correlated with the CO gas diffusivity of the atmosphere in that the CO partial pressure acts as the driving force for the formation reaction in question. Furthermore, the results indicate that the reaction rate of Mn7C3 formation under H2 gas is significantly faster than that under He gas; that is because methane gas that is formed by the reaction between H2 with carbon accelerates the overall reduction process. On the other hand, a high CO partial pressure is shown to retard the formation reaction of Mn7C3.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Mechanics of Materials
- Metals and Alloys
- Materials Chemistry