Phase Transformations of TIMETAL-18 as a New Titanium Alloy with Bimodal Microstructure

Abstract:

In this work, we have investigated the microstructural evolutions and the phase transformations of a new near-beta alloy with a nominal composition of Ti-5.5Al-5V-5Mo-2.4Cr-0.75Fe-0.15O (weight percent), the TIMETAL 18 [here after called Ti-18]. The complete microstructural state of the Ti-18 during heat treatments, from as quenched metastable state, has been first investigated. The phase transformations have been studied by combination of X-ray diffraction analysis, metallurgical observations and electrical resistivity measurements. From a series of isothermal treatments, the first complete TTT diagram has been then established displaying three C-curves corresponding to different precipitation domains for alpha phase.

• Periodical: Advanced Materials Research (Volume 922)
• Pages: 418-423
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.922.418
• Online since: May 2014
• Authors: E. Lebrun*, Peter Svec, S. Nowak, B. Denand, Y. Millet, Frédéric Prima
• Keywords: Bimodal Microstructure, Mechanical Property, Microstructural Evolution, Resistivity Measurements, Titanium Alloy

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