Shape Memory Effect and Superelasticity in High-Strength FeNiCoAlTi Single Crystals Hardened by Nanoparticles

For [001]-oriented single crystals of Fe-28Ni-17Co-11.5Al-2.5Ti (at %) alloy in tension, it was shown that particles of the gamma'-phase with a size of 4-6 nm lead to the appearance of superelasticity, with a strain of epsilon(SE) = 4.5% and a shape memory effect of epsilon(SME) = 5.9%. Increasing the particle size to 10-12 nm reduces epsilon(SE) to 3.6% and epsilon(SME) to 3.5%. The paper discusses the causes of the influence of particle size on the reversible strain.