About this Abstract |
Meeting |
MS&T22: Materials Science & Technology
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Symposium
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Processing-Microstructure-Property Relationships of Titanium and Titanium Alloys
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Presentation Title |
Slip-twinning Interdependency in High-strength Alpha-beta Titanium Alloys |
Author(s) |
Shaolou Wei, John W. Foltz, Joseph Jankowski, Bhuvi Nirudhoddi, Luis Ruiz-Aparicio, C. Cem Tasan |
On-Site Speaker (Planned) |
Shaolou Wei |
Abstract Scope |
Alpha-beta titanium alloys like Ti-6Al-4V are used because of their high specific-strength. In lower strength alloys like Ti-3Al-2.5V, alpha twinning is commonly observed and leads to higher ductility due to increased number of deformation modes. Alloys with yield strengths above 800 MPa typically do not exhibit alpha twinning, and tend to have poor cold-formability. Recent titanium alloys developed by ATI (ATI 425®, ATI Titan 27TM) have demonstrated simultaneously strength above 800 MPa and the activation of twinning in the alpha phase along with interdependent twinning-slip transfer. Interestingly, both alloys contain higher oxygen content than Ti-6Al-4V, and oxygen has previously been linked to suppression of alpha twinning. This presentation primarily aims to explore the micro-mechanical consequences of the interdependent slip-twinning activity, specifically, its influence on plastic strain localization and partitioning. The chemical origin of the twinning mechanism will also be discussed with the assist of density functional theory calculations. |