Damping Characteristics of Biomedical Porous NiTi Shape Memory Alloy

One internal friction peak associated with the B2↔B19’ transformation appears on the cooling curve of porous NiTi shape memory alloy and the dense NiTi alloy shows the maximum peak. The tan δ value increased with the increasing of strain amplitude and the decreasing of frequency. Tan δ value of porous alloy mainly comes from the energy absorbing of the matrix at the small strain amplitude, however, if the strain amplitude is large, the tan δ value comes from the energy consumption that overcomes the friction between folds and the plastic contribution.