Two-Way Bending Properties of Shape Memory Composite with SMA and SMP

Hisaaki Tobushi,Yoshiki Sugimoto,Kousuke Date,Shunichi Hayashi

doi:10.3390/ma2031180

Hisaaki Tobushi, Yoshiki Sugimoto + Show 2 more

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https://doi.org/10.3390/ma2031180

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Abstract

A shape memory composite (SMC) was fabricated with a shape memory alloy (SMA) and a shape memory polymer (SMP), and its two-way bending deformation and recovery force were investigated. The results obtained can be summarized as follows: (1) two kinds of SMA tapes which show the shape memory effect (SME) and superelasticity (SE) were heat-treated to memorize the round shape. The shape-memorized round SMA tapes were arranged facing in the opposite directions and were sandwiched between the SMP sheets. The SMC belt can be fabricated by using the appropriate factors: the number of SMP sheets, the pressing force, the heating temperature and the hold time. (2) The two-way bending deformation with an angle of 56 degrees in the fabricated SMC belt is observed based on the SME and SE of the SMA tapes during heating and cooling. (3) If the SMC belt is heated and cooled by keeping the bent form, the recovery force increases during heating and degreases during cooling based on the two-way properties of the SMC. (4) The development and application of high-functional SMCs are expected by the combination of the SMA and the SMP with various kinds of phase transformation temperatures, volume fractions, configurations and heating-cooling rates.

Highlights

The intelligent materials, which respond to optical, electrical or thermal actions from outside and perform various kinds of high function, have been developed and have attracted worldwide attention.Metals, ceramics and polymers have been developed as intelligent materials and applied widely to the fields of industry, aerospace, medical treatment and the products related to daily life
The symbols Af,SE, Af,shape memory effect (SME) and Tg shown in Figure 9 represent the reverse-transformation finish temperatures of the SE-shape memory alloy (SMA) tape and the SME-SMA tape and the glass transition temperature of the shape memory polymer (SMP) sheet, respectively
The elastic modulus of the SMP decreases at temperatures around Tg of the SMP, the recovery force of the SME-SMA tape is smaller than that of the SE-SMA tape, and the recovery force of the shape memory composite (SMC) belt is almost the same as that at temperatures around Af,SE

Summary

Introduction

The intelligent materials, which respond to optical, electrical or thermal actions from outside and perform various kinds of high function, have been developed and have attracted worldwide attention. Ceramics and polymers have been developed as intelligent materials and applied widely to the fields of industry, aerospace, medical treatment and the products related to daily life. One of the main materials which have developed this research and applications are shape memory alloys (SMAs) [1,2,3]. Shape memory polymers (SMPs) have been used practically [4,5,6]. In the SMA, the shape memory property appears based on the martensitic transformation (MT) in which the crystal structure varies depending on the variation in temperature.

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