Temperature dependence of mechanical damping in Ni–Mn–Ga austenite and non-modulated martensite

The temperature dependence of damping properties of the Ni52.3Mn27.4Ga20.3 alloy was studied in the temperature range of 308–473 K. The vibration damping capability of this 2M martensite structure increases above a certain stress level, corresponding well to the twinning stress values observed previously. This triggering stress decreases with increasing temperature. The dominant damping mechanism of the martensitic phase is related to the twin boundary movement. In the martensite–austenite two-phase region, tan δ decreases above a maximum stress value.