Influence of Pulse-Plasma Treatment Distance on Structure and Properties of Cr3C2-NiCr-Based Detonation Coatings

In this work, the coatings obtained by a combined method, including Cr3C2-NiCr coating applied using a multichamber detonation device and subsequent pulse-plasma treatment, were investigated. This paper presents the results of an investigation of the influence of the pulse-plasma treatment (PPT) exposure distance on the structural-phase state of the surface layer of Cr3C2-NiCr-based detonation coatings. It was seen that after the PPT melting and alignment of the structural elements of coatings there were no signs of coating destruction from the impact of plasma pulses. It was established that the microstructure of the coatings was a molten metal-ceramic material based on Cr3C2-NiCr. It was also found that after pulse-plasma treatment, Cr2O3 chromium oxide phases are found on the surface, and the intensity of Cr3C2 peaks increased and new Cr3C2 reflexes appeared. It was further found that after pulse-plasma treatment the microstructure became more homogeneous, which led to the densification of the Cr3C2-NiCr-based detonation coating. It was established that the pulse-plasma treatment (PPT) contributed to increased hardness of the Cr3C2-NiCr coating material, from similar to 13.4 GPa (before PPT) to similar to 17.6 GPa (after PPT) and wear resistance twice that of the non-treated coating. The abrasive wear resistance and erosion resistance of Cr3C2-NiCr coatings were improved after pulse-plasma treatment.