Damping behavior of TiNi-based shape memory alloys

The damping behavior of TiNi-based alloys has been investigated by dynamic mechanical analyzer (DMA) instruments. It shows that an appropriate cold-rolling deformation on the martensitic Ti50Ni50 alloy can enhance its damping capacity. The damping behavior of the Ti49.2Ni50.8 alloy is aging condition dependent and the damping capacity peak value corresponding to the phase transformation increases due to the increase of the amount of boundaries between the martensite and parent phase as a result of the existence of the Ti3Ni4 particles. The Ti44Ni47Nb9 alloy possesses high damping capacity either during phase transformation or in the parent phase, which is very important for the engineering application.