Shape Memory Materials

High glass-transition polyurethane-carbon black electro-active shape memory nanocomposite for aerospace systems

“…Shape memory of the prepared SMPC was tested using the well-accepted fold-deploy test, where the composite sample was bend to U-shaped specimen, constrained and heated to temperature Tg + 20°C for temporary shape fixing [9]. The system was then cooled below Tg to evaluate the shape fixity (R f in % by measuring the angle of recovery).…”

“…SMPC to be used for aerospace applications requires them not to get disintegrated when exposed to harmful ultraviolet radiations. The demand for remote actuation and getting away with external heaters have led the development of electro-active SMP composites with different types of fillers (carbon nanotubes -CNT, carbon black-CB, graphene, carbon nanofibers-CNF, fullerenes or metal fillers like nickel powder) [1,3,[5][6][7][8][9][10][11][12][13][14]. It induces electrical conductivity so that actuation by means of Joule-heating can be achieved, as in NiTi-SMA (NiTinol) [3,[15][16][17][18][19][20].…”

Structural-modelling and experimental validation of percolation threshold for nanotube-polyurethane shape memory system

“…The shape memory behaviour of the prepared nano composite was assessed using a fold-deploy test in which the SMPC was initially bent to a defined U-shape and subsequently heated to a temperature of approximately 20°C above T g to train for shape fixing [4]. The system was then cooled below T g in order to retain the trained 'U' shape and the angle of fixity was then calculated using a graduated protractor to get shape fixity efficiency, R f .…”

“…Additionally, the incorporation of fillers has further enhanced electrical conductivity by augmenting other characteristics of the materials, including mechanical and thermal, etc. [4][5][6][7].…”

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

“…SMMs are advantageous to design compliant (flexible and joint-less) mechanisms, and they became an important research subject in many engineering areas, including robotics, biomedical science, aerospace technology, or civil structures [1]. In sustainable architecture, SMMs are used to make silent and sensor-less climate-responsive building components [2,3].…”