Study of Two-Way Shape Memory Behavior of Amorphous-Crystalline TiNiCu Melt-Spun Ribbons

Abstract

Recently we reported on the development of a composite material exhibiting reversible shape memory effect. A Ti–25Ni–25Cu (at.%) alloy was obtained by the melt spinning technique as amorphous–crystalline ribbons with a thickness of approximately 40 μm. The thickness of the amorphous and crystalline layers (dа and dc, respectively) was varied by electrochemical polishing. It has been ascertained that with varying the relationship dc/dа the martensite transformation and shape-recovery temperatures do not actually change, while the minimum radius of the ribbon bending decreases from 8.0 mm to 2.4 mm with increasing the relationship dc/dа from 0.33 to 1.40. The maximum reversible strain comprises 0.4% at dc/dа = 0.82. On the basis of experimental data obtained the phenomenological description, providing an explanation for nature of the phenomena taking place in the rapidly quenched amorphous-crystalline ribbon composite, has been proposed.

Pseudoelasticity response of aged Ti50Ni25Cu25 shape memory ribbon under nanoindentation tests

“…With aging time longer than 15 min, the intensity of TiCu diffraction peaks gradually increase but that of B2 peaks decrease. These features are in good agreement with the DSC results, indicating that B11 TiCu precipitates significantly affect the transformation behavior of aged Ti 50 Ni 25 Cu 25 ribbons when the aging time is longer than 15 min. Fig.…”

“…9). Experimental results indicate that the PE properties of 500 C-aged Ti 50 Ni 25 Author agreement statement 1. All authors have participated sufficiently in this work to take public responsibility for it.…”

“…Because amorphous Ti 50 Ni 25 Cu 25 ribbon can be obtained at the as-spun condition, the crystallization behavior of the ribbon has been investigated [20,22]. Many researchers have also carefully investigated the effects of heat-treatment/crystallization temperatures on the properties of the ribbon, including transformation behavior [17,23], microstructure [18,24] and two-way SME [25,26]. Shelyakov et al [27,28] chose Ti 50 Ni 25 Cu 25 ribbons for MEMS application.…”

“…Ti 50 Ni 25 Cu 25 ribbons have been studied extensively in the past decade. Because amorphous Ti 50 Ni 25 Cu 25 ribbon can be obtained at the as-spun condition, the crystallization behavior of the ribbon has been investigated [20,22].…”

A low temperature in-situ crystalline TiNi shape memory thin film deposited by magnetron sputtering

“…Magnetron sputtering is the most suitable method due to lower contamination and high purity films and adjustment of the atomic ratio, growing structure and film thicknesses by controlling the deposition parameters [5][6][7][8][9]. The basis of the shape memory is the transformation of phases [10]. The phases consist of martensite (B19) at low temperatures and austenite (B2)/ the main phase at high temperatures [11].…”