|About this Abstract
||Materials Science & Technology 2017
||Fifty Years of Metallography and Materials Characterization
||Correlating Variability in Fatigue Life with Fracture Mechanisms in a Near-αTitanium Alloy
||Vikas Sinha, Sushant Jha, Adam Pilchak, William Porter, Reji John, James Larsen
|On-Site Speaker (Planned)
Unlike the quasi-static mechanical properties, such as strength and ductility, fatigue life can vary significantly for nominally identical material and test conditions in many materials, including Ti-alloys. This makes life prediction and management more challenging for components that are subjected to cyclic loading in service. The differences in fracture mechanisms can cause the variations in fatigue life. In this study, the fatigue fracture mechanisms are investigated in a near-<I>α</I> titanium alloy, Ti-6Al-2Sn-4Zr-2Mo, which had been tested under condition that resulted in life variations by more than an order of magnitude. Both short and long life specimens are examined for this alloy in two different microstructural conditions. The crack-initiation and small crack growth processes, including their contributions to fatigue life variability, are elucidated via quantitative characterization of fatigue fracture surfaces. The spatial and crystallographic orientations of fracture features were determined in an SEM with quantitative tilt fractography and EBSD, respectively.
||Planned: Publication outside of MS&T