Study on the synergistic diffusion mechanism of double glow plasma alloying and its impact on the magnetic properties of non-oriented silicon steel

This research investigates the element distribution, binding energy, and diffusion behavior of 3.5 wt% Si non-oriented electrical steel through carburization, nitridation, and carbonitridation processes, utilizing molecular dynamics simulation and double glow discharge surface alloying technology. Simulation results reveal a specific synergistic diffusion effect between carbon and nitrogen elements in the steel, with nitrogen playing a dominant role in promoting the diffusion depth of carbon in the steel. The double glow plasma surface alloying experiments demonstrate that as the carbon-to-nitrogen ratio increases, the carbon content rises and then declines, reaching its peak at a carbon-to-nitrogen ratio of 1:5, where both carbon and nitrogen contents achieve their maximum values. This phenomenon indicates that an appropriate carbon-to-nitrogen ratio effectively enhances the diffusion of both carbon and nitrogen elements in the matrix. In addition, nitriding significantly reduces the saturation magnetization of non-oriented electrical steels by approximately 20 %, with carbonitriding having the least effect on magnetic properties.