Abstract
Morphology of secondary grain boundary α phase (αGB) has great influence on grain boundary Widmanstätten α phase (αWGB) cluster and further fracture toughness and ductility of the titanium alloys. In this paper, the bifurcation behavior and morphology of secondary αGB in TC18 titanium alloy were investigated through high and low temperature two-step heat treat experiment (910 °C/30 min→800 °C/45 min/WQ) combined with a three-dimensional reconstruction experiment. It was found that αGB showed flat, equiaxed, zig-zag morphologies, and αGB bifurcated to reduce the energy of the system and maintained the stability of structure by interfacial instability nucleation. There exist two types of bifurcation behaviors, bi-direction bifurcation and tri-direction one. The significant difference between them is nucleation positions, β/β grain boundary or the triple junction (TJ) of β grain boundary. The bifurcation behavior of α phase at TJ is related to its original morphology. Bi-direction bifurcation occurs mostly in the flat αGB, but is not observed in the zig-zag αGB. The present results provide new information on αGB of TC18 titanium alloy.
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.
