Tension-compression asymmetry of Fe-Ni-Co-Al-X (X= Nb, Ti, Nb-Ti) shape memory alloys – Impact of nanocrystalline precipitates on functional properties
Final Report Abstract
Shape memory alloys (SMA) based on iron (Fe-based), in particular the alloy Fe-Ni-Co-Al-X (X= Ta, Ti, Nb, Ti-Nb), show great potential in terms of functional properties while being costefficient. Ni-Ti, representative of a conventional alloy system, is more expensive in terms of the cost of the individual alloying elements and processing. This makes Fe-based SMA attractive for many industrial applications. In most studies, the effects of tensile-compressive asymmetry and orientation dependence were investigated in quasi-static tests. A few studies investigated the effects of γ'-precipitation on the functional properties and functional fatigue in the Fe-Ni-Co-Al-Ta system. The overall aim of this project was to gain a comprehensive understanding of the heat treatment parameters that influence the properties of these Febased SMAs. The functional properties of Fe-based SMAs can be determined by critical precipitation parameters. Therefore, the focus was on the identification of promising heat treatment strategies to adjust the precipitation parameters in order to improve the functional performance in the Fe-Ni-Co-Al-X (X= Ta, Ti, Nb, Ti-Nb) alloy system. The aim was to develop a new family of precipitates that exhibit a core-shell character, i.e. they show a chemical gradient between the core and the shell of a precipitate. In a first step, the effects of different heat treatments to introduce finely divided precipitates and the resulting martensitic transformation were investigated. In the second step, the most promising precipitation parameters of the alloy system were derived and adapted to the Fe-Ni-Co-Al-Ti-Nb system. A two-stage precipitation matrix with different temperature levels and exposure times was used to promote precipitation with a core-shell structure, since the diffusion coefficients of Nb and Ti are different. The driving force of Gibbs free energy for the martensitic transformation is influenced by a systematic variation of the precipitation properties, the surrounding stress fields and the local chemistry of both the precipitates and the matrix. The aim of this approach was to evaluate how the functional properties can be tailored by adjusting the precipitates.
Publications
-
Shape memory effect and superelasticity in high-strength FeNiCoAlTi single crystals hardened by nanoparticles. AIP Conference Proceedings, 2167, 020064. AIP Publishing.
Chumlyakov, Yuriy; Kireeva, Irina; Kuksgauzen, Irina; Poklonov, Vyacheslav; Pobedennaya, Zinaida; Bessonova, Irina; Kuksgauzen, Dmitriy; Kirillov, Vladimir; Lauhoff, Christian; Niendorf, Tomas & Krooß, Philipp
-
Effect of β- and γ'-phase particles on the shape memory effect and superelasticity in [0 0 1]-oriented FeNiCoAlTi single crystals. Materials Letters, 260, 126932.
Chumlyakov, Y.I.; Kireeva, I.V.; Kuksgauzen, I.V.; Poklonov, V.V.; Pobedennaya, Z.V.; Bessonova, I.G.; Kirillov, V.A.; Lauhoff, C.; Niendorf, T. & Krooß, P.
-
On the Impact of Texture and Grain Size on the Pseudoelastic Properties of Polycrystalline Fe–Ni–Co–Al–Ti Alloy. Shape Memory and Superelasticity, 6(2), 191-201.
Sobrero, C. E.; Lauhoff, C.; Wegener, T.; Niendorf, T. & Krooß, P.
-
Shape memory effect and superelasticity in high-strength FeNiCoAlTiNb single crystals. AIP Conference Proceedings, 2310, 020065. AIP Publishing.
Chumlyakov, Yuriy; Kireeva, Irina; Pobedennaya, Zinaida; Kuksgauzen, Irina; Poklonov, Vyacheslav; Krooß, Philipp; Niendorf, Tomas; Lauhoff, Christian & Vollmer, Malte
-
Impact of test temperature on functional degradation in Fe-Ni-Co-Al-Ta shape memory alloy single crystals. Materials Letters, 291, 129430.
Sobrero, Cesar; Lauhoff, Christian; Langenkämper, Dennis; Somsen, Christoph; Eggeler, Gunther; Chumlyakov, Yuri I.; Niendorf, Thomas & Krooß, Philipp
-
Rubber-like behaviour and superelasticity of [001]-oriented FeNiCoAlNb single crystals containing γ′- and β-phase particles. Journal of Alloys and Compounds, 856, 158158.
Chumlyakov, Yu.I.; Kireeva, I.V.; Pobedennaya, Z.V.; Krooβ, P. & Niendorf, T.
-
Shape Memory Effect and Superelasticity of [001]-Oriented FeNiCoAlNb Single Crystals Aged under and without Stress. Metals, 11(6), 943.
Chumlyakov, Yuriy I.; Kireeva, Irina V.; Pobedennaya, Zinaida V.; Krooß, Philipp & Niendorf, Thomas
-
Tension-compression asymmetry of the superelastic behavior of high-strength [001]-oriented FeNiCoAlNb crystals. Materials Letters, 289, 129395.
Chumlyakov, Yu.I.; Kireeva, I.V.; Kuksgauzen, I.V.; Kuksgauzen, D.A.; Niendorf, T. & Krooβ, P.
-
The Influence of Heat Treatmnet and Stress State on Functional and Mechanical Properties of [001]-Oriented FeNiCoAlTi Single Crystals. Russian Physics Journal, 63(9), 1596-1604.
Kuksgauzen, I. V.; Chumlyakov, Yu. I.; Kireeva, I. V.; Poklonov, V. V.; Kuksgauzen, D. A.; Kirillov, V. A.; Lauhoff, C.; Niendorf, Т. & Krooß, P.
-
Cyclic Superelastic Behavior of Iron-Based Fe-Ni-Co-Al-Ti-Nb Shape Memory Alloy. Journal of Materials Engineering and Performance, 32(19), 8593-8599.
Lauhoff, C.; Remich, V.; Giordana, M. F.; Sobrero, C.; Niendorf, T. & Krooß, P.
