Change dynamics of alloy VT6 structure from ingot to alloyed material

The modern development of technology and industry depends to a large extent on improving the quality and performance of equipment. Additive technologies allow production of optimized designs and equipment while maintaining all operational characteristics. The use of additive technologies in the production of parts for aerospace engineering requires a thorough study of the operational properties of materials at each stage of production, a comparative assessment of the test results with the parameters of products obtained by traditional technologies, as well as predicting the characteristics of the final product. In this work, a study of changes in the chemical and phase compositions, microstructure and microhardness of the VT6 titanium alloy samples was carried out at various stages of production: initial cast billet; a powder obtained by plasma centrifugal spraying of an ingot and a product obtained by selective laser melting (SLM). Analysis of the samples’ chemical composition was carried out on an X-ray fluorescence spectrometer with wave dispersion Rigaku Primus ZSX II, X-ray structural studies – on a Rigaku MiniFlex 600 diffractometer (CuK_α -radiation, λ = 1.54178 Å), equipped with a linear (1-D) D/teX semiconductor detector. Study of the microstructure of powder (granular) samples was carried out using the methods of optical and scanning electron microscopy, the measurement of microhardness – on a microhardness tester LECO M-400-H by the Vickers method. It was shown that microstructure of the samples after centrifugal sputtering was a combination of two solid solutions based on the hexagonal titanium modification (HCP) with slightly different crystal lattice parameters due to difference in concentrations of the alloying elements. Chemical composition of the alloy after selective laser melting practically did not differ from the alloy in the initial state.

additive technologies, VT6, selective laser melting, powder, microstructure

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