Tension-compression asymmetry of the superelastic behavior of high-strength [001]-oriented FeNiCoAlNb crystals

•Effect of two-step ageing was studied in [001]-FeNiCoAlNb crystals.•Tension-compression asymmetry of superelasticity was observed.•Maximum superelasticity of 11.5% was found in compression. Temperature dependence of the stresses σcr of stress-induced γ-α′ martensitic transformations (MT) and superelasticity (SE) were studied in tension and compression on [001]-oriented Fe-27Ni-17Co-11.7Al-2.9Nb (FeNiCoAlNb) (at.%) crystals after two-step ageing (973 K, 0.5 h + 723 K, 3h). It was shown that the α = dσcr/dT value does not depend on the stress state (tension/compression) in the range of the stress-induced γ-α′ MT. SE depends on the stress state and the maximum SE strain of 11.5% was observed in compression.