The effect of tensile deformation on the damping capacity of NiTi shape memory alloy

The vibration damping capacity of a near-equiatomic NiTi shape memory alloy was characterized as a function of tensile deformation by utilizing dynamic mechanical analysis. The intrinsic internal friction (IF) values of the martensite phase (Qint,m−1) decreased with increasing deformation levels up to 10%, attributed to a decrease in the density of martensite variant and twin boundaries. Deformation increased the temperature of the transformation peak during the first reverse transformation of thermal cycling. A two-stage behavior was observed in terms of the IF values of the transformation peak. IF reached a peak value at 4%, dropped at 5% and monotonically increased again up to 10% deformation. Thermal cycling partially restored Qint,m−1 levels and shifted the transformation peak close to its undeformed IF and temperature values during the second reverse transformation. •Internal friction of SMAs is dependent on the amount of internal interfaces.•Uniaxial deformation decreases the amount of internal interfaces.•A decrease in internal interfaces leads to a decrease in damping capacity.•Reverse transformation through heating restores the damping capacity values.