Internal friction behavior related to martensitic transformation of a CuAlNiMnTi shape memory alloy

Internal friction behavior related to martensitic transformation of a CuAlNiMnTi shape memory alloy is examined in the study. Two internal friction peaks are observed when measuring frequency is lower than 0.045 Hz, in which the low-temperature peak corresponds to the minimum of relative dynamic modulus while the high-temperature peak to the reflection point of relative dynamic modulus. The maximum value of the low-temperature peak shows a linear relationship with frequency only when frequency is below 0.025 Hz otherwise bears a complicated non-linear relationship. In addition, it tends to be a constant rather than continuously increasing as heating rate increases. These results are very different from generally observed phenomena.