Microwave sintering of Ti(C,N)-based cermets: Study of the magnetic effect on metal phase

For microwave heating of Ti(C,N)-based cermets, this paper presents a microwave heating simulation study of pure Ti(C,N) ceramics and Ti(C,N)-based cermets using Comsol software. S-parameter inversion is employed to determine the equivalent relative permittivity of Ti(C,N)-based cermets with varying metal contents. The pairwise Ni metal plate model is utilized to investigate the law of mutual coupling voltage between metal plates. It was found that vigorous electric field intensity is generated around the metal particles of Ti(C,N)-based cermets, and high electric field intensity is generated between the metal particles. Model slice analysis and mechanism analysis are combined to reveal the following phenomena: (1)The surface of metal particles in Ti(C,N)-based cermets excites induced electromagnetic fields; (2)High mutual coupling voltages are generated between metal particles; (3)The reflection effect of metal particles on microwaves can increase the electric field intensity between metal particles. By statistically analyzing the temperature data of pure Ti(C,N) ceramics and Ti(C,N)-based cermets during the initial 30-min microwave sintering period, the temperature difference changing law can be concluded: (1)During the initial 30 min of microwave sintering, the temperature difference between the two gradually increased with time; (2)At 30 min, the temperature difference between the two reached 111 °C.