Effect of Primary Microstructures during Training Producers on TWSME in NiTi Alloys

The influence of the martensitic, martensitic+austenitic and austenitic structures during bending training on two-way shape memory effect (TWSME) in Ni-50.8 at %Ti and Ni-49.9 at %Ti alloys hasbeen studied. In addition, the effect of pre-strain, plastic strain, training cycle and training temperatureon the TWSME has been investigated. Specimens were trained in martensitic, martensitic+austenitic and austenitic states with bending deformation. The results showed that in martensitic state, TWSME was more than the other states. Although the number of training cycles in martensitic state(10-15cycle) were less than the other training methods (15-25 cycle), the obtained optimum pre-strain in martensitic state (16%) was more than other training methods (12%). In addition, it was shown that with increasing the training temperature in austenitic state, TWSME decrease

Keywords:

Shape Memory Alloy , Training , Primary Structure , TiNi