The hardmetal Cr3C2-25NiCr (180-220 μm thick) coatings have been produced on a steel substrate by a new multi-chamber gas-dynamic accelerator. The Cr3C2-25NiCr powder (POLEMA JSC, Russia) (35-140 μm) was used as the starting material to deposit a dense layer. A detailed analysis of the features of the coatings structure on all the levels of the structure (from grain to dislocation) (phase composition, distribution of the disperse phase, grain nature, subgrains and dislocation structures) was conducted. The structural-phase state of the coatings was characterized using SEM, TEM, and XRD techniques. It was established that phase composition of Cr3C2-NiCr powder under the influence of high temperatures and the atmosphere of detonation products changes with the formation of a complex heterogeneous structural-phase state in the coatings. A layered structure of the regions of carbide particles and matrix metal was found in the immediate vicinity of the "carbide-matrix" boundary with the precipitates in the matrix of dispersed secondary carbides. It was shown that the nanocomposite Cr3C2-NiCr coatings are characterized by the presence of nanodispersed ceramic compounds. Lamellae in the coatings consisted of nanocrystalline grains, separated by interlayers of the amorphous phase and oxide crystalline grains.Keywords: gas-dynamic accelerator, Cr3C2 – NiCr, nanocomposite coatings, microstructure, TEM
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