State of Ni–Cr–B–Si–Fe/WC coatings after plasma powder surfacing with nanopowder modifier

Abstract

The structure and phase state and internal stress fields of plasma powder Ni–Cr–B–Si–Fe/WC surface coatings are compared in the presence and absence of a modifier: Al₂O₃ nanoparticles. PS-12NVK-01 powder alloy applied to a steel 20 substrate is studied by transmission diffraction electron microscopy of thin films, scanning electron microscopy, and X-ray structural and local X-ray spectral analysis. The phase composition of the alloy is determined; its defect structure and internal stress are studied. The structure of the material is analyzed before and after the introduction of Al₂O₃ nanopowder in the melt. Introducing the modifier reduces the grain size of the material; leads to the formation of tungsten carbide W₂C and the boride Fe₃Ni₃B in the carbide subsystem; and reduces the internal stress and scalar dislocation density.