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Abstract Ni 24.7 Ti 50.3 Pd 25 and Ni 24.7 Ti 49.3 Pd 25 Sc 1 high-temperature shape memory alloys were thermo-mechanically processed and characterized in the present study. The microstructural characteristics of cold-worked alloys showed the presence of shear/deformation bands and defects. TEM observation of cold-worked and annealed (400 to 500 °C) microstructures revealed the emergence of small fraction of newly formed martensite twins at 400 °C. With the increase in the annealing temperature from 400 to 500 °C, the fraction of the martensite twins in the microstructure was found to increase. The Ni 24.7 Ti 50.3 Pd 25 and Ni 24.7 Ti 49.3 Pd 25 Sc 1 alloys showed martensite finish temperature of ~180 °C and ~136 °C with an hysteresis of ~10 °C and ~9 °C, respectively. Ni 24.7 Ti 50.3 Pd 25 and Ni 24.7 Ti 49.3 Pd 25 Sc 1 alloys showed a recovery strain of 1.5% and 1.7% at a stress of 175 MPa. During cycling under load, the residual strain for the Ni 24.7 Ti 49.3 Pd 25 Sc 1 alloy was found to be negligible as compared to ~0.2% in the Ni 24.7 Ti 50.3 Pd 25 alloy. The results of the study indicate that these alloys have potential for use as high-temperature thermal actuator materials. Highlights • TEM of cold-worked NiTiPd/NiTiPdSc showed shear/deformation bands and defects. • Cold-worked and annealed microstructures revealed emergence of fine-scale twins at 400 °C. • Fraction of martensite twin-variants increased with increase in annealing temperature. • NiTiPd and NiTiPdSc alloys showed a recovery strain of 1.5% and 1.7% at a stress of 175 MPa. • Thermo-mechanical cycling of NiTiPdSc exhibited lower residual deformation compared to NiTiPd. [ABSTRACT FROM AUTHOR]