Low Temperature Superplasticity of Ti-6Al-4V Processed by Warm Multidirectional Forging

Abstract:

Multidirectional forging has been developed to produce an ultrafine-grain (UFG) microstructure in the two-phase titanium alloy Ti-6Al-4V. A microstructure with a grain size of 135 nm was attained, enabling low-temperature superplasticity (LTSP) at 550°C. A total elongation of 1000% and strain-rate-sensitivity coefficient m=0.47 were obtained at the optimal strain rate of 2×10^-4 s^-1. Important features of the microstructure and superplastic behavior of the alloy are summarized in the present work. It is shown that microstructure evolution during low-temperature deformation plays a key role in superplastic flow behavior.

• Periodical: Materials Science Forum (Volume 735)
• Pages: 253-258
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.735.253
• Online since: December 2012
• Authors: Gennady A. Salishchev, Egor A. Kudryavtsev, Sergey V. Zherebtsov, S. Lee Semiatin
• Keywords: Low-Temperature Superplasticity, Microstructure Evolution, Multidirectional Forging, Ultrafine Grain Structure

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