Abstract: Three kinds of NiTi films with different Ni contents were prepared by DC magnetron sputtering. The crystallization kinetics of amorphous films was determined by using non-isothermal single-scan techniques. The results show that the activation energy of crystallization of Ni-rich NiTi film(Ni 51.10 at. pct, Ti 48.90 at. pct) is 715 kJ/mol, while that of Ti-rich films are similar: one is 445 kJ/mol (Ni 46.74 at. pct, Ti 53.26 at. pct), the other is 418 kJ/mol (Ni 43.21 at. pct, Ti 56.79 at. pct), which is lower than Ni-rich film. The Avrami parameter n of different films are 0.92 and 0.74 for Ni-rich film and Ti-rich films, respectively. The difference of kinetic parameters for NiTi films with various Ni contents implies that the crystallization behaviors of these films are distinct, which is confirmed by the calculated isothermal kinetics at different temperatures. The thorough research on this phenomenon is in progress.

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