Applied Mechanics and Materials Vol. 692

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.

Abstract: Aiming at the deficiency of the current asphalt mixture test procedures using the traditional Marshall compaction molding test specimens method to evaluate water stability of asphalt mixture, large size aggregate particle asphalt mixture water stability test method, evaluation index and standard are proposed, namely the freeze-thaw cycles dynamic stability ratio index is adopted to evaluate asphalt mixture water stability, the freeze-thaw cycles dynamic stability ratio ≥ 85% is required and verified by experiment.