Processing Induced Change οf Thermal Transport Properties οf NiTi-Shape Memory Alloy

Photothermal radiometry was applied to investigate the influence of a rolling process on the thermal properties of NiTi foils. The thermal diffusivity and thermal effusivity of the foils were determined at room temperature from the frequency variation of the photothermal signals in thermal transmission. Measurements were conducted on unrolled, rolled and thermally annealed samples. The thermal diffusivity and thermal effusivity are found to decrease considerably on rolling which is attributed to the influence of the rolling induced lattice defects.