Study on Preparation of Ferrite Composite Coating with Magnetoplumbite Phase Structure by Plasma Spraying

In order to solve the problem of direct preparation of magnetoplumbite phase structure ferrite coating by thermal spraying, the ferrite/polyethylene composite coating was prepared by plasma spraying process, and the phase structure and microstructure morphology of the composite coating were studied.Results showed that the thickness of ferrite/polyethylene composite coating was 1 mm.Spinel phase and magnetoplumbite phase existed simultaneously in the coating, with spinel phase accounting for 55% and magnetoplumbite phase accounting for 45%.In addition, many un-melted phases existed in the coating but there was no typical lamellar structure in the coating.By sacrificing polyethylene to protect the magnetoplumbite ferrite, the low melting point polyethylene was melted and ablated first in the spraying process, which took away part of the heat of the plasma flame flow, so that some magnetoplumbite ferrite had insufficient heat absorption and could not be fully melted.There was no melting cooling crystallization and the transformation process from spinel crystal form to magnetoplumbite crystal form, but retained the original magnetoplumbite phase structure deposited into the coating.Through this method, the composite coating of ferrite with magnetoplumbite structure was prepared by plasma spraying.