Influence of Thermomechanical Cyclic Methods on Training NiTi Alloy for Two-way Shape Memory Effect

The influence of different training methods on producing two-way shape memory effect in NiTi alloy is investigated.Four typical thermomechanical cyclic methods are adopted to train NiTi wire to establish two-way shape memory effect and assessed in terms of two-way recoverable deformation,changes in the hot shape,cold shape and transformation temperatures.The results indicate that loading NiTi wire at different material phases is the main reason for different training effects obtained by these methods.In particular,the dislocations introduced by loading during the martensite transformation are the most advantageous to the formation of two-way shape memory effect.