Abstract
An approach for producing bulk products of intermetallic Ti-25Al, Ti-46Al and Ti-22.9Al-22.7Nb-2.4(Zr,V,Si,C) alloys with a submicrocrystalline structure is proposed. The approach is based on multi-step a-b-c hot forging with a reducing forging temperature. During forging dynamic recrystallization occurred resulting in continuous grain refinement as the working temperature decreased. Grain sizes from 0.1 to 0.5 μm were produced in the titanium aluminide alloys. The production of a nanocrystalline structure of size d<0.1 μm using this method seemed to be unfeasible since drastic embrittlement of the alloys took place which may be ascribed to partial disordering of the titanium aluminide alloys. The intermetallic materials with submicrocrystalline structures exhibited superplastic properties in a wide temperature range (600-1000°C). In the fully ordered Ti-25Al alloy room temperature ductility increased with decreased grain size, while ductility of partially disordered Ti-25A1 and ordered Ti-46Al alloys was close to zero at room temperature. The increased ductility was found to be correlated with an enhanced grain boundary relaxation capability at increased temperature and decreased grain size.
Sign-in/Register to access full text options 
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.
