изико-механические свойства керамических покрытий, получаемых короткоимпульсной лазерной наплавкой порошковой смеси на основе бора

Abstract

Modern repair production that implements traditional technologies for making restorative coatings has lost its relevance, since it cannot provide the necessary physical and mechanical properties of the coatings. The problem is that in modern metallurgy there is no line of repair additive materials with high strength and technological properties. Therefore, the issues of searching for innovative materials and technologies for their application on the surface of worn parts are relevant and require fundamental research. The aim of the work is to study the physical and mechanical properties of ceramic coatings obtained by short-pulse laser treatment. To achieve this goal, ceramic compositions based on boron carbide, additionally doped with boron nitride (0 to 40% BN), magnesium oxide (2 to 10% MgO) and lithium (5 to 25% LiO), were used. The scientifi c novelty of the research lies in the application of selective laser sintering technologies in the formation of thin coatings (up to 200 μm) under conditions of a short-pulse laser refl ow of powder media. To assess the physical and mechanical properties, laboratory research methods were used, in particular, analysis of the microhardness of the created restorative coatings, microstructure and tribological performance indicators using modern techniques and instrumentation. The research results confi rm the possibility of practical implementation of restorative coatings based on ceramic compounds. The multi-layer ceramic coatings (B4C-BN- MgO-Li2O) up to 200 μm thick showed good workability, low coeffi cient of friction (0.18) and the ability to work under high dynamic loads in the absence of intensive lubrication. The structure of the coatings has a dense adhesive zone with no visible defects. The presented results of studying the physic-mechanical properties of ceramic coatings have high research credentials and practical signifi cance, and their application will improve the durability of machine parts in the conditions of their operation.