Application of Co-Ni-P coating on grain-oriented electrical steel

An electroless plating of Co-Ni-P was applied to a grain-oriented electrical steel substrate resulting in a power loss improvement of approximately 9-11 %. The mean thickness of the coating was found to be 2.15±0.15 μm from Environmental Scanning Electron Microscope (ESEM) images. Shifts of the magnetostriction stress sensitivity curves showed that stress was acting on the substrate corroborated by a shift in X-ray Diffraction (XRD) peaks and narrowing of the domains after the samples were coated. The magnetic property measurement system (MPMS) results confirmed the magnetic nature of the coating and XRD results showed peaks of α-Iron in uncoated sample, α-Iron-Cobalt and α-Iron in Co-Ni-P coated sample. The Talysurf profilometer showed a decrease in surface roughness (Ra) values after coating the sample which reduced the hysteresis loss.