Abstract
Ti15Mo metastable beta Ti alloy was solution treated and subsequently deformed by high-pressure torsion (HPT). HPT-deformed and benchmark non-deformed solution-treated materials were annealed at 400 °C and 500 °C in order to investigate the effect of UFG microstructure on the α-phase precipitation. Phase evolution was examined using laboratory X-ray diffraction (XRD) and by high-energy synchrotron X-ray diffraction (HEXRD), which provided more accurate measurements. Microstructure was observed by scanning electron microscopy (SEM) and microhardness was measured for all conditions. HPT deformation was found to significantly enhance the α phase precipitation due the introduction of lattice defects such as dislocations or grain boundaries, which act as preferential nucleation sites. Moreover, in HPT-deformed material, α precipitates are small and equiaxed, contrary to the α lamellae in the non-deformed material. ω phase formation is suppressed due to massive α precipitation and consequent element partitioning. Despite that, HPT-deformed material after ageing exhibits the high microhardness exceeding 450 HV.
Highlights
The interest in metastable β-Ti alloys has gradually increased due to their high specific strength, which make them ideal for applications in the aerospace industry [1]
The results indicate that the high-pressure torsion (HPT)-deformed alloy is a two-phase with volume fractions and ω phase sample
Metastable β titanium Ti15Mo alloy was prepared by HPT and subsequently aged at 400 ◦ C and 500 ◦ C
Summary
The interest in metastable β-Ti alloys has gradually increased due to their high specific strength, which make them ideal for applications in the aerospace industry [1]. Manufacturing of medical implants and devices is another high-added-value field and constitutes a prospective application of metastable β titanium alloys [2]. These alloys offer higher strength levels than commonly used α + β alloys due to controlled precipitation of tiny particles of α phase [3]. Ti-based alloys can be further improved by achieving an ultra-fine grained (UFG) structure via severe plastic deformation methods (SPD) [4,5,6,7]. Manufacturing of UFG metastable β-Ti alloys is of significant. This study focuses on the effect of microstructure refinement by SPD on the precipitation of α phase upon subsequent thermal treatment
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
