THE EFFECT OF LAYERING ON THE PROPERTIES OF METAL-CERAMIC COATINGS OBTAINED BY DETONATION SPRAYING

Aiym Nabioldina, Aiym Nabioldina, Balym Alibekova, Garip Erdogan, Aibek Alibekov

This work presents the results of a study of multilayer metal-ceramic coatings based on the NiCr/NiCr- Al2O3/ Al2O3 system obtained by detonation spraying. Coatings with different numbers of layers were obtained: three-layer (NiCr, 50% NiCr – 50% Al2O3, Al2O3), five-layer (NiCr, 75% NiCr – 25% Al2O3, 50% NiCr – 50% Al2O3, 25% NiCr – 75% Al2O3, Al2O3) and six-layer (NiCr, Al2O3, NiCr, Al2O3, NiCr, Al2O3). The study aims to establish the influence of layering and gradient distribution of components on the microstructural, phase, mechanical, and tribological characteristics of coatings. The microstructural features of the coatings were studied using scanning electron microscopy in backscattered electron (BSE) mode and energy dispersive spectral analysis (EDS). The phase composition was analyzed by X-ray phase analysis. Microhardness and surface roughness measurements were performed, as well as tribological tests at a temperature of 700 °C. It was found that five-layer coatings with a gradient structure with a gradual transition from a metal layer to a ceramic layer demonstrate the best performance characteristics among all the samples studied. The five-layer coatings were characterized by high microhardness, uniform surface roughness, minimal counterbody penetration depth, and a stable friction coefficient in wear tests.

multilayer coating, metal ceramics, NiCr/NiCr- Al2O3/ Al2O3, detonation spraying, gradient structure, microstructure, X-ray phase analysis, tribological properties.