It is known that the thermokinetic electromotive force (EMF) in TiNi is induced due to thermoelastic phase transformations. The occurrence of thermokinetic EMF is possible both with the movement of the heating zone and the local cooling zone along the extended TiNi sample. Local heating of the conductor determines reverse phase transformation (T ≥ Аs), while cooling - forward phase transformation (T ≤ Мs). When the thermo-kinetic EMF is induced in TiNi wire sample, two consecutive EMF peaks of different signs are observed during the displacement of the cooling zone through the deformation zone (Ldef <1.4 cm); after the cooling zone passes through the deformation zone, the thermokinetic EMF value returns to its initial value .This paper presents a physical model according to which the change in the thermokinetic EMF value during the movement of the cooling zone through the deformation zone is associated with the appearance of the potential difference at the boundaries of the deformed zone due to changes in temperature and differences between the thermo-EMF coefficient values on the plastically deformed (due to accumulated defects) and undeformed zone of TiNi wire sample. Mathematical expressions are obtained for calculating the change of thermokinetic EMF value during the movement of the cooling zone through the zone of deformation in TiNi alloy, as well as the dependence of this value on the deformation degree, the length of the deformed zone, and temperature in the cooling zone. The calculated results show good agreement with experimental data and can be used for developing methods and tools for controlling homogeneity in TiNi products.
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