Strengthening strategy for a ductile metastable β-titanium alloy using low-temperature aging

F. Sun (1) , Jin-Ying Zhang , P. Vermaut (1) , D. Choudhuri (2) , T. Alam (2) , S.A. Mantri (2) , P. Svec , T. Gloriant (3) , P.J. Jacques , R. Banerjee (2) , F. Prima (1)

1 IRCP - Institut de Recherche de Chimie Paris
2 Department of Materials Science and Engineering
3 ISCR - Institut des Sciences Chimiques de Rennes

While ω precipitates in metastable β titanium alloys are typically considered embrittling and consequently deleterious to the mechanical properties, this paper demonstrates that low-temperature aging (LTA) treatments for short time periods can in fact enhance the yield strength while preserving substantial elongation-to-failure in ω containing β titanium alloys. LTA treatments, carried out on a ductile β metastable Ti–12Mo alloy, significantly improve the yield strength of the material (∼55% increase as compared to solution-treated samples) while keeping both TRIP/TWIP effects and a large elongation-to-failure (ϵ = 0.4 in true strain), resulting in a balance of mechanical properties. IMPACT STATEMENT Employing a novel low-temperature annealing strategy, omega precipitates, typically considered embrittling in beta titanium alloys, can effectively increase the yield strength by 50% while preserving 40% tensile ductility.

Keywords: mechanical properties; omega phase; thermal treatment; β titanium alloys

Domains: Chemical Sciences

F. Sun, Jin-Ying Zhang, P. Vermaut, D. Choudhuri, T. Alam, et al.. Strengthening strategy for a ductile metastable β-titanium alloy using low-temperature aging. Materials Research Letters, 2017, 5 (8), pp.547-553. ⟨10.1080/21663831.2017.1350211⟩. ⟨hal-01639686⟩