Regensburg 2016 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DS: Fachverband Dünne Schichten

DS 12: Postersession DS

DS 12.7: Poster

Montag, 7. März 2016, 17:00–19:00, Poster A

evaluation of structure and mechanical properties of Ni-rich/ Ti-rich NiTi thin film — •Maryam Mohri^1,2, Mahmoud Nili-ahmadabadi², Julia Ivanisenko¹, and Horst Hahn¹ — ¹Karlsruhe Institute of Technology, Institute of Nanotechnology, 76021 Karlsruhe, GermanyKarlsruhe Institute of Technology, Institute of Nanotechnology, Karlsruhe, Germany — ²School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, Iran.

NiTi alloys have received more attraction for a wide range of smart designs and innovative applications due to shape memory effect and pseudo elasticity. In this paper, the gradient structure and mechanical properties of a martensitic/austenitic (Ni49Ti/Ni51Ti (at.%)) bi-layered thin film with 1000nm thickness deposited using DC magnetron sputtering on Si substrate and subsequent annealing were studied. The structure, transformation temperatures and mechanical properties of the bi-layer were analyzed using grazing incidence X-ray diffraction (GIXRD), scanning transmission electron microscopy, differential scanning calorimetry (DSC) and nanoindentation. The X-ray diffraction results indicated that the bi-layer was composed of austenitic and martensitic layers. The bi-layered thin film exhibited a combined pseudo elastic behavior and shape memory effect specific to the austenitic and martensitic thin films, respectively. The combination of pseudo elastic effect with shape memory leads to a two-way shape memory effect with a reduced hysteresis in the bi-layers.