Experimental Analysis of NiTi Alloy during Strain-Controlled Low-Cycle Fatigue

The interaction between the stress-induced martensitic transformation and resistivity behavior of superelastic NiTi shape memory alloy (SMA) was studied. Strain-controlled low-cycle fatigue up to 6% was monitored by in situ electrical resistivity measurements. The experimental results show that a great motion of martensite fronts results in a significant accumulation of defects, as evidenced by transmission electron microscopy (TEM), before and after the tensile cycles. This gives rise to an overall increase of the resistivity values up to the maximum deformation. Therefore, the research suggests that shape memory alloy wire has great potential as a stress sensor inside bulk materials.

Automated summary

The study of stress-induced martensitic transformation and resistivity behavior in the superelastic NiTi shape memory alloy revealed that significant motion of martensite fronts during tensile cycles resulted in the accumulation of defects and an overall increase in resistivity values. This suggests that shape memory alloy wire has great potential as a stress sensor inside bulk materials.