Functionally Graded Ti-Ni Shape Memory Alloys


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Shape memory characteristics and superelasticity of an temperature gradient annealing(TGA) treated equiatomic Ti-Ni alloy have been investigated by means of differential scanning calorimetry(DSC), thermal cycling tests under constant load and tensile tests. By annealing 25% cold worked alloy under the temperature gradient from 658 K to 466 K, 7 K variation in TR*and 19 K variation in Ms* were obtained along the length of sample(150mm). Temperature dependence of transformation elongation(dε/dT) of TGA treated Ti-Ni alloy wires was in the range of 0.05 %/K and 0.01 %/K depending on annealing temperature ranges. The dε/dT obtained from TGA treated sample under the temperature gradient from 658 K to 466 K was 0.03 %/K. TGA treated alloy showed the clear superelastic recovery.



Materials Science Forum (Volumes 539-543)

Main Theme:

Edited by:

T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran




T. H. Nam et al., "Functionally Graded Ti-Ni Shape Memory Alloys", Materials Science Forum, Vols. 539-543, pp. 3169-3172, 2007

Online since:

March 2007




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