Material Synthesis by Thermal Plasma Processing

The Fe-TiN composite is synthesized in-situ using a non-transferred arc D.C. plasma reactor from ilmenite ore concentrate using methane and nitrogen as the reactive gases. The alloy composition was selected based on the thermodynamics assessment. The standard Gibbs energy minimization method is used to calculate the equilibrium composition of the reacting species.

The plasma reactor system consists of reaction chamber, quenching cylinder and filter cylinder. The reactor is heated with PT-50C plasma torch (PEC) having a maximum power of 100 kW. All the parameters will be monitored with a computer data acquisition system. The products will be characterized with SEM, EDAX, and X-ray diffraction. Process parameters are evaluated to improve the efficiency.

A mathematical model is developed to describe the plasma gas and particle dynamics and conversion yields. The velocity and temperature fields in the plasma are calculated by solving the Navier-Stokes equations and the thermal energy balance equations. Conservation equations for the system species consider the multi-component diffusion and chemical reactions. Through the application of this model, temperature distribution, flow fields, and production rates are computed. The model will be used to study the thermal decomposition of ilmenite in the non-transferred arc plasma reactor.