Texture and Twinning in Selective Laser Melting Ti-6Al-4V Alloys

Authors: N. Kazantseva, P. Krakhmalev, I. Yadroitsev, A. Fefelov, N. Vinogradova, I. Ezhov, T. Kurennykh

Abstract:

Martensitic texture-phase transition in Selective Laser Melting (SLM) Ti-6Al-4V (ELI) alloys was found. Electron Backscatter Diffraction (EBSD) analysis showed the initial cubic beta < 100 > (001) BCC texture. Such kind of texture is observed in BCC metals with flat rolling texture when axis is in the direction of rolling and the texture plane coincides with the plane of rolling. It was found that the texture of the parent BCC beta-phase determined the texture of low-temperature HCP alpha-phase limited the choice of its orientation variants. The {10-12} < -1011 > twinning system in titanium alloys after SLM was determined. Analysis of the oxygen contamination in SLM alloys was done. Comparison of the obtained results with the conventional titanium alloys is also provided.

Keywords: Additive technology, texture, Ti-6Al-4V, twins, oxygen content.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1132773

References:

[1] A.M. Beese, B.E. Carroll,” Review of mechanical properties of Ti-6Al-4V made by laser-based additive manufacturing using powder feedstock”, JOM, vol. 68, pp. 724-734, 2016.
[2] E. Wielewski, C. R. Siviour and N. Petrinic, “On the correlation between macrozones and twinning in Ti–6Al–4V at very high strain rates,” Scripta Materialia, vol. 67, pp. 229–232, 2012.
[3] M. Simonelli, Y. Y. Tse, C.Tuck, “Further understanding of Ti-6Al-4V selective laser melting using texture analysis”, Journal of Physics : Conference Series, vol.371, pp.1-4, 2012.
[4] H. Miura, Y. Itoh, , T. Ueamtsu, K. Sato, “The influence of density and oxygen content on the mechanical properties of injection molded Ti-6Al-4V alloys”, Advances in Powder Metallurgy and Particulate Materials, vil.1, pp.46-53, 2010.
[5] A. M. Bauristhene, K. Mutombo, W .E. Stumpf, “Alpha case formation mechanism in Ti-6Al-4V alloy investment castings using YFSZ shell moulds”, Journal of the Southern African Institute of Mining and Metallurgy, vol.113, pp.357-361, 2013.
[6] W. Tirry, F. Coghe, L. Rabet and D. Schryvers, “Multi-scale observations of deformation twins in Ti6Al4V” in EMC, vol. 2: Materials Science, S. Richter, A. Schwedt, Ed., 2008, , pp. 499–500.
[7] J. Peirsa, W. Tirryb, B. Amin-Ahmadib, F. Coghec, P. Verleysena, L. Rabetc, D. Schryversb, J. Degriecka, “Microstructure of adiabatic shear bands in Ti6Al4V”, Materials characterization, vol.75, pp.79 -92, 2013.
[8] P. Krakhmalev, G. Fredricsson, I.Yadroitseva, N. Kazantseva, A. Du Plessis, I.Yadroitsev, “Deformation Behavior and Microstructure of Ti6Al4V Manufactured by SLM”, Physics Procedia, vol. 83, pp. 778 – 788, 2016.
[9] L. Bao, C. Schuman, J-S.Lecomte, M-J. Philippe, X. Zhao and C. Esling, “A Study of Twin Variant Selection and Twin Growth in Titanium”, Advanced engineering materials. vol.13, no. 10, pp.928-932. 2011.
[10] I.V. Egis, A. A. Barbeko, A. I. Horev, M. M. Martinova, E. B. Samarin, “Basic texture formation in VT18u titanium alloy”, Metal Science and Heat Treatment, no 6, pp. 1-7, 1992.