National Research Nuclear University MEPhI, Moscow, Russia:

M. G. Isaenkova, Professor, e-mail: isamarg@mail.ru
Yu. A. Perlovich, Professor
A. V. Yudin, Post-Graduate Student
A. E. Rubanov, Student, e-mail: toly.rubanov@yandex.ru

The regularities of crystallographic texture formation in samples with different geometry, produced by selective laser melting (SLM) of the titanium VT1-0 alloy powder were studied. The texture in massive samples (plate, bar and cube) is formed during the crystallization of the β-phase with the subsequent phase transformation β → α while maintaining the orientational ratio of Burgers. As the product grows along the Z axis, the initial axial texture of the lowest layers with the <111>_β axis parallel to the Z direction changes to the texture with the <110>_β || Z^β axis at a distance of 0.5 mm and then to the stable limited texture {001}<100>_β for the remaining upper part of the product. In the upper layer of the product, the texture is scattered due to the termination of the SLM process. It is shown, that the formation of texture in the middle layers of the product is conditioned by the growth of columnar β-phase crystals, which are formed due to the thermal effect of the molten region on the underlying layers. The texture of the supporting structure does not affect the texture of the product itself. The layer-by-layer change in the mechanical properties of materials along the Z axis correlates with the variation of the crystallographic texture. The anisotropy of the hexagonal structure predetermines the substantial anisotropy of the properties of the product.
This work was carried out with the financial support of the State Program for Improving the Competitiveness of the National Research Nuclear University MEPhI (Agreement No. 02.a03.21.0005).

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