Аңдатпа
Abstract— The article presents the results obtained from experimental studies of Cr3C2–NiCr coatings applied, using the detonation-spraying method, on grade 12Kh1MF heat-resistant steel, including those on the effect that the Cr3C2–NiCr coating application process technological parameters have on the coating’s structure and properties. In the tests, a detonation gun with a single dosing device was used. Detonation gun spraying is one of the methods for thermally producing a protective layer on the surface, characterized by the fact that it allows hard, wear resistant and dense microstructured coatings to be obtained. Acetylene–oxygen mixture served as combustible gas, which is most frequently used for detonation spraying of powder materials. A nitrogen or air pulse is used for purging the gun barrel after each detonation. This process is repeated several times a second. A high kinetic energy of hot powder particles, as they collide against the substrate, results in that a very dense and strong coating is produced. The obtained coatings have a heterogeneous layered porous structure with undulate location of 60–120 µm-thick structural components with the layered-porous structure. There are no pores or cracks at the substrate-to-coating interface. The profile arithmetic mean deviation Ra is selected as the key roughness measurement parameter. It has been determined that, with the gun barrel volume filled by 64% with explosive mixture, the processed sample surface features a low wear degree. The results from studying the effect that the detonation spraying has on the coating structural-phase composition and tribological properties using the X-ray structural analysis method are given, which have shown that the Cr3C2, Cr7C3, Cr3O6, Cr23C6, and CrNi3 phases are produced. The microhardness, roughness, and tribological properties of the obtained coatings have been determined.