Наплавлені покриття з використанням органічних підкладок

Abstract

The article explores the possibility of using organic materials added to the welding bath during surfacing in a carbon dioxide environment, the processes of structure formation and the hardness indices of the formed coatings. It is established that the introduction of cellulosebased organic materials allows obtaining high-carbon coatings of considerable hardness on samples of low-carbon steel, in the process of surfacing in a medium of carbon dioxide. The transition zone between the surfacing using an organic substrate and the workpiece metal is 1.5 mm thick has a fine-grained ferrite - pearlitic and somewhat striped structure in the form of a cementitious mesh. The formation of such a structure is explained by the high cooling rate of the welding bath due to heat dissipation into the metal of the sample, and the increased carbon content in this zone, which is the result of dissolution of the organic substrate. The microstructure of the coating has a pearlitic structure, with a cementitious mesh. The ratio of the structural components can be changed by adjusting the amount of organic material introduced and surfacing modes. The adjustable amount of cementite in the coating has a positive effect on the wear resistance, but the crack resistance is not impaired. The possibility of applying high carbon coatings of considerable thickness and area with high productivity and efficiency is shown. Analysis of the microstructure and dyurometric analysis of the deposited layers showed that in the deposited zone the greatest amount of cementitic mesh and, accordingly, the highest hardness, which positively affects the physical and mechanical properties of the coating.