IN-SITU SYNTHESIS OF MULTICOMPONENT ALLOYS FROM Ni BASED ELEMENTAL POWDERS BY DIRECT LASER DEPOSITION

The paper investigates an approach to the synthesis of classical heat-resistant alloys by laser cladding (LC) or direct laser deposition (DLD). This approach corresponds to the concept of developing the production of small parties of metal products with the economically feasible use of additive technologies. The results of already obtained materials from pure elemental powders and the prospects for the development of such formation of alloys from the liquid phase, as well as metal-matrix composites by 3D printing, are discussed. The paper presents the result of a specimen formation from a mechanical mixture of Ni / Cr / Fe powder, in the mass ratio of the main components, close in composition to the alloy Inconel 600. The produced multilayer specimen was studied by optical and electron microscopy. Measurement of fluctuations in the chemical composition in the specimen to determine the degree of diffusion of elements in the alloy was carried out. The formation of chromium oxide clusters along the boundaries of the tracks, which, presumably, diffuse in the direction of heat removal during crystallization from the melt, was found. The structure of the specimen is represented by large, elongated grains up to 1-2 mm in size, significantly exceeding the height of one pass. The direction of grain growth corresponds to the growth direction of the specimen in the direction of the Z axis.