Structural characteristics and high-temperature friction properties of a solid metal surface with a laser-melted coating of high-entropy alloy

Abstract This article presents the results of a study on composite coatings based on high-entropy FeCoNiCrCuNb alloys with varying niobium content obtained through high-speed laser cladding. The primary objective of the research is to investigate the influence of composition on the structure, mechanical characteristics, and behaviour of the coatings. Microstructure analyses were performed using scanning electron microscopy and energy-dispersive spectroscopy analysis. The microhardness, shear strength, and coefficient of friction of the composite coatings were examined. It was demonstrated that the microstructure of the coatings is characterized by fine grains and the presence of columnar crystals. An increase in copper content leads to a transition to the face-centred cubic phase with elevated niobium content, influencing the mechanical characteristics. It was revealed that niobium-containing composite coatings exhibit improved mechanical properties and wear resistance. The incorporation of niobium synergistically affects the mechanical characteristics of the alloys. The obtained results hold practical applicability in the field of engineering, particularly where wear resistance and strength are of paramount importance.