Journal Article

Compressive response of Ni45.3Ti34.7Hf15Pd5 and Ni45.3Ti29.7Hf20Pd5 shape-memory alloys

Chumlyakov, Y. I., Karaca, H. E., Tobe, H., Kaya, I., Acar, E.

2015

Overview

The shape-memory properties of Ni 45.3 Ti 34.7 Hf 15 Pd 5 and Ni 45.3 Ti 29.7 Hf 20 Pd 5 polycrystalline alloys were determined through superelasticity and shape-memory tests in compression. It has been revealed that the Ni 45.3 Ti 34.7 Hf 15 Pd 5 has a maximum transformation strain of 3.8 % and work output of up to 30 J cm −3 , while the Ni 45.3 Ti 29.7 Hf 20 Pd 5 has a maximum transformation strain of 2.6 % and work output of up to 20 J cm −3 at 700 MPa. Two-way shape-memory strains of 0.6 and 0.85 % were obtained in Ni 45.3 Ti 34.7 Hf 15 Pd 5 and Ni 45.3 Ti 29.7 Hf 20 Pd 5 alloys, respectively. The Ni 45.3 Ti 34.7 Hf 15 Pd 5 showed superelasticity at 90 °C with recoverable strain of 3.1 %, while high hardening of Ni 45.3 Ti 29.7 Hf 20 Pd 5 limited its superelastic behavior. Microstructure of the Ni 45.3 Ti 34.7 Hf 15 Pd 5 alloy was revealed by transmission electron microscopy, and effects of composition on the lattice parameters of the transforming phases and martensite morphology were discussed.

• Publisher: Springer US,Springer Nature B.V
• Subject: Characterization and Evaluation of Materials / Chemistry and Materials Science / Classical Mechanics / Composition effects / Compression tests / Crystallography and Scattering Methods / Lattice parameters / Martensite / Martensitic transformations / Materials Science / Mathematical morphology / Original Paper / Polymer Sciences / Recoverable strain / Shape memory alloys / Solid Mechanics / Superelasticity / Transmission electron microscopy