An investigation of forming of Ti-6Al-4V at lower temperatures

An investigation of forming of Ti-6Al-4V at lower temperatures

Hosam Elrakayby, Diego Gonzalez, Paranjayee Mandal, Paul Blackwell

Abstract. Forming components of titanium alloys via superplastic forming at elevated temperatures while being exposed to oxygen leads to surface oxidation. The hard oxide layer formed on the surface of components is referred to as the alpha case. This alpha case layer requires post-form processing to remove it, thus increasing overall manufacturing costs and times. Superplastic forming at lower temperatures can significantly reduce the formation of the alpha case and has other benefits, such as life extension of tooling and less energy consumption. This paper shows the work done in terms of forming non-commercial components at temperatures significantly lower than the traditional ones, proving that forming at those temperatures is readily achievable. Forming pressures and tonnage need to be readjusted because of the increase in the flow stresses of the material. This paper also illustrates the implementation of a microstructural-based model to predict the hot forming behaviour of commercial titanium alloy Ti-6Al-4V (Ti64) during forming at 800°C. The material model is implemented into a commercial finite element software, Abaqus, and PAM-STAMP to obtain the optimal pressure cycle to form a non-commercial research component at 800 °C with a view to minimizing alpha case formation.

Keywords
Superplastic Forming, Titanium, Ti-6Al-4V, Alpha Case

Published online , 9 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Hosam Elrakayby, Diego Gonzalez, Paranjayee Mandal, Paul Blackwell, An investigation of forming of Ti-6Al-4V at lower temperatures, Materials Research Proceedings, Vol. 32, pp 55-63, 2023

DOI: https://doi.org/10.21741/9781644902615-5

The article was published as article 5 of the book Superplasticity in Advanced Materials

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

References
[1] R.R. Boyer, An overview on the use of titanium in the aerospace industry, Mater. Sci. Eng. A. 213 (1996) 103-114. https://doi.org/10.1016/0921-5093(96)10233-1
[2] E. Alabort, P. Kontis, D. Barba, K. Dragnevski, R.C. Reed, On the mechanisms of superplasticity in Ti-6Al-4V, Acta Mater. 105 (2016) 449-463. https://doi.org/10.1016/j.actamat.2015.12.003
[3] E. Alabort, D. Putman, R.C. Reed, Superplasticity in Ti-6Al-4V: Characterisation, modelling and applications, Acta Mater. 95 (2015) 428-442. https://doi.org/10.1016/j.actamat.2015.04.056
[4] P. Mandal, A. Gomez-Gallegos, D. Gonzalez, H. Elrakayby, P. Blackwell, Superplastic Behaviour of Ti54M and Ti64, MATEC Web Conf. 321 (2020) 04028. https://doi.org/10.1051/matecconf/202032104028
[5] F. Pitt, M. Ramulu, Influence of grain size and microstructure on oxidation rates in titanium alloy Ti-6Al-4V under superplastic forming conditions, J. Mater. Eng. Perform. 13 (2004) 727-734. https://doi.org/10.1361/10599490421394
[6] G.A. Salishchev, R.M. Galeyev, O.R. Valiakhmetov, R. V. Safiullin, R.Y. Lutfullin, O.N. Senkov, F.H. Froes, O.A. Kaibyshev, Development of Ti-6Al-4V sheet with low temperature superplastic properties, J. Mater. Process. Technol. 116 (2001) 265-268. https://doi.org/10.1016/S0924-0136(01)01037-8
[7] R.S. Mishra, V. V. Stolyarov, C. Echer, R.Z. Valiev, A.K. Mukherjee, Mechanical behavior and superplasticity of a severe plastic deformation processed nanocrystalline Ti-6Al-4V alloy, Mater. Sci. Eng. A. 298 (2001) 44-50. https://doi.org/10.1016/S0921-5093(00)01338-1
[8] H. Matsumoto, K. Yoshida, S.H. Lee, Y. Ono, A. Chiba, Ti-6Al-4V alloy with an ultrafine-grained microstructure exhibiting low-temperature-high-strain-rate superplasticity, Mater. Lett. 98 (2013) 209-212. https://doi.org/10.1016/j.matlet.2013.02.033
[9] J. Lin, T. Zhu, L. Zhan, Constitutive equations for modelling superplastic forming of metals, in: Superplast. Form. Adv. Met. Mater., Elsevier, 2011: pp. 154-183. https://doi.org/10.1533/9780857092779.2.154
[10] T.G. Langdon, Grain boundary sliding revisited: Developments in sliding over four decades, J. Mater. Sci. 41 (2006) 597-609. https://doi.org/10.1007/s10853-006-6476-0
[11] H. Elrakayby, D. Gonzalez, A. Gomez-Gallegos, P. Mandal, N. Zuelli, A Study on Modelling the Superplastic Behaviour of Ti54M Alloy, Solid State Phenom. 306 (2020) 9-14. https://doi.org/10.4028/www.scientific.net/SSP.306.9