Thermoelastic strain in polycrystalline Fe–Pd shape memory alloy thin film

Abstract

Thermoelastic strain in a polycrystalline Fe–Pd thin film due to shape memory effect was determined from Hooke's law using the measured residual stress and the elastic modulus obtained by the wrinkling method, and the variation in the thermoelastic strain was discussed in terms of thermally induced phase transformation. The measurement of thermoelastic strain from Hooke's law and the wrinkling method was in good quantitative agreement with previously reported data obtained from a digital camera. The variation of thermoelastic strain of the Fe-28.1at.% Pd thin film was associated with the martensitic transformation between the high-temperature face-centered cubic austenite and the low-temperature face-centered tetragonal martensite during a thermal cycle.