Full-Field Strain Behavior of Friction Stir-Welded Titanium Alloy by Digital Image Correlation

Abstract:

Experimental investigation is conducted to examine, evaluate, and characterize the fundamental elastic-plastic stress/strain response of friction stir-welded butt joints in thin-sheet, fine grain Ti-6Al-4V titanium alloy under normal tensile loading using traditional global stress-strain tensile testing and the full-field displacement measurement techniques of Digital Image Correlation (DIC). It was found that overall strength of friction stir-welded Ti-6Al-4V is comparable to the accepted values for mill-annealed Ti-6Al-4Valloy. Overall strain performance of friction stir-welded Ti-6Al-4V is roughly half that of the accepted values for pure mill-annealed Ti-6Al-4V. In addition, friction stir-welded Ti-6Al-4V demonstrates a consistent pattern of strain localization between the onset of yielding and ultimate failure.

• Periodical: Applied Mechanics and Materials (Volume 692)
• Pages: 490-496
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.692.490
• Online since: November 2014
• Authors: Mamidala Ramulu*, Trent Greenwell, Paul Labossiere
• Keywords: Digital Image Correlation, Friction Stir Welding, Full-Field Measurements, Moiré Interferometry, Titanium

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