Intelligent Shape Memory Actuators

Abstract

The shape memory alloy has played an important role to develop the intelligent materials and structures. The shape memory polymer has also been used in practical applications. If the shape memory materials are applied into actuators, the novel intelligent shape memory actuators can be developed. In the present paper, the development of a functionally-graded shape memory alloy actuator, a functionally-graded shape memory polymer actuator and a shape memory composite actuator is discussed. The simple multi-way actuation can be developed by using the functionally-graded shape memory alloy wire and tape. The functionallygraded shape memory polymer board, showing a similar deformation property to a finger, can be applied to the elements coming into contact with body in the medical actuators. The three-way and three-dimensional actuators of simple mechanism can be developed by applying the shape memory composite with various kinds of shape-memory alloy and polymer.

A Sensitivity Analysis of Geometric Parameters of 4D-Printed Bidirectional Shape-Memory Composite in Architectural Façade Design

“…Figure 9 finds that this parameter combination suits reversibility of the designed morphing as predicted, exhibiting maximum δ of ~3.5 mm at T = [30°C, 65°C]. In many SMM applications, although SMP is not generally considered as a bias material because of the limited recovery force, our test demonstrates that a well-designed SMP composite enables to create reliable force for shape recovery, and it parallels the experimental suggestions of Matsui et al [24] and Kang et al [25]. However, unlike theoretical assumption in the modeling, the sheathed fibers were not completely flattened at austenite.…”

An investigation of the corrosion behaviour of a FeNiCoAlTa shape memory alloy in 3.5 wt-% NaCl solution

“…in the early 1980s [1], Fe-based shape memory alloys (SMAs) have become more attractive due to their lower cost, good mechanical properties, wide range of high temperature applications and workability compared to the Ni–Ti SMAs [1 -3]. They have shown strong potentials for use as fasteners and pipe couplings [4 -7], solid-state actuators [5,8 -10] and in civil engineering applications [11,12]. Understanding the corrosion properties of Fe-based SMAs attracted several studies in the early 1990s [13,14] with the main focus being to improve their corrosion resistance through additions of alloying elements such as Cr, Al, Ni, Mn, Cu, Si, N and RE [13,15 -24].…”

4D-printed parametric façade in architecture: prototyping a self-shaping skin using programmable two-way shape memory composite (TWSMC)

“…An SMC is created by combining an SMP matrix (SMPM) body and two SMA fibers (SMFs) to suit reversible two-way SME. SMPs are not generally considered for bias actuation due to their limited force exertion, but Matsui et al. (2017b) demonstrated recovery force of SMPs can be exploited for multi-way deformation.…”

“…To concern these issues, SMM hybrids or shape memory composites (SMCs) synthesizing several materials have been attempted, satisfying field-specific requirements (Arun et al. , 2018; Matsui et al. , 2017b; Meng et al.…”