|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||The Effect of Initial Microstructure on the Mechanical Properties of Bi-lamellar Ti-6Al-4V
||Yan Chong, Nobuhiro Tsuji
|On-Site Speaker (Planned)
Bi-lamellar microstructure can be realized by intercritical annealing followed by rapid cooling of lamellar microstructure in titanium alloys. The mechanical properties can be improved by the introduction of fine secondary α lamellars in-between coarse α lamellars in the bi-lamellar structures. In this study, the influence of initial microstructures, including martensite microstructure and lamellar microstructure, on the resulting bi-lamellar microstructures as well as its mechanical properties was systematically investigated. Colony size was significantly reduced by starting from martensite microstructure compared with that started from lamellar microstructure. Consequently, both yield strength and uniform elongation of bi-lamellar microstructure were improved. The improvement was explained by decreased slip length based on “effective” grain size of two different scales, i.e., α lamellar thickness and α colony size. In addition, the phenomenon of crack propagation through secondary α lamellar with certain orientation is discussed.
||Planned: A print-only volume