Abstract
The fatigue crack growth behavior of forged Ti-46.5Al-3Nb-2Cr-0.2W (at.%) was investigated. Heat treatments were used to generate both a nearly fully lamellar microstructure (grains of α 2- γ lamellae) and a duplex microstructure (equiaxed γ and lamellar grains) to span the wide range of microstructural conditions available through thermomechanical processing of these alloys. Fatigue crack growth tests using load-shedding threshold and constant-load-amplitude techniques were conducted at room temperature, 600 °C (below the ductile-to-brittle transition temperature (DBTT)) and 800 °C (above the DBTT). Results show that the fatigue crack growth resistance of the lamellar microstructure is superior to that of the duplex microstructure. The nature of fatigue crack advance depends strongly on microstructure, which explains, at least in part, the differences observed in crack growth rates for the lamellar and duplex microstructures. Fractography was conducted to identify the dominant crack growth mechanisms in both the lamellar and duplex microstructures.
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.
