Influence of thermomechanical training deformations on TWSME in TiNiCu alloy spring

The effect of the different thermomechanical training deformations on the two-way shape memory effect (TWSME) in TiNiCu shape memory alloy spring has been systematically studied. TiNiCu SMA springs show various two-way shape memory recovery rates through thermomechanical training processes when five different training deformations are employed. It is found that the two-way shape memory recovery rate increases with increasing training deformation till about the training deformation 250 mm and then it starts decreasing. When the training deformation is 250 mm, the maximum two-way shape memory recovery rate is obtained. After training and thermal cycling, the transformation temperatures As and Af are obviously lower than corresponding to the untrained sample and Ms and Mf are affected slightly.