Smart material

About: Smart material is a research topic. Over the lifetime, 3704 publications have been published within this topic receiving 74280 citations. The topic is also known as: intelligent material & responsive material.

Electrical switch for smart PH self-adjusting system based on silver nanowire/polyaniline nanocomposite film

Abstract: A sensitive pH-triggered electrical switch is demonstrated by using a layer-structured silver nanowire/polyaniline nanocomposite film fabricated via an easy vertical spinning method. The as-prepared nanocomposite film shows the high electrical conductivity of 1.03 × 104 S cm–1 at the Ag-NW areal density of 0.84 mg cm–2 and a good cycling stability. Particularly, because of the layered structure, the switch achieves a very high contrast ratio of ca. 9 × 108, which is 2–6 orders higher than that reported previously. The high electrical conductivity and the high switching ratio make the layer-structured nanocomposite film a sensitive switch candidate for pH-responsive systems. Finally, a smart pH self-adjusting switching system is successfully designed using the as-prepared layer-structured nanocomposite film.

Embedded Fiber Optic Sensors Within Additive Layer Manufactured Components

Abstract: Smart materials with integrated sensing capabilities are now ubiquitous in many structures and devices manufactured from composite materials and they offer enhanced safety, reliability and efficiency in such smart devices. This paper explores the application of embedded sensors to components manufactured using additive layer manufacturing (ALM) technology. ALM offers the ability to create physical parts with little or no restriction in shape and complexity. In this paper, optical fiber sensors incorporating fiber Bragg gratings are embedded inside a component made by, and during a powder-bed-based, layer-by-layer, additive manufacturing process. A commercial EOS P730 system is used, where a laser is employed to sinter the polymeric powder into a 3D component. The fiber embedding approach is based upon insertion of a “fiber-carrier” component, which replaces a removable “place-holder” component during an interruption of the ALM build process. Tensile test specimens fabricated this way are subjected to extended cyclic tensile loading trials at low strain levels of up to 580 μe . The test specimens demonstrate stable and reproducible responses over a period in excess of 720 days and 311000 load cycles. Polyimide and acrylic jacketed fibers are trialled, and the resulting deformations of the component through internal stresses depending on the fiber jacket type are discussed.

Bottom-Up: Can Supramolecular Tools Deliver Responsiveness from Molecular Motors to Macroscopic Materials?

Abstract: Summary Motion is omnipresent, as is obvious from the artificial machines in the macro-world and the biomolecular motors in living systems, controlling dynamic behavior along many length scales. With the emergence of molecular machines in the past decades, a major step has been made toward responsive materials and dynamic molecular systems. Photochemical rotary molecular motors hold a unique position, as embedding nanoscale motors in macroscopic materials enables light-driven responsive and adaptive properties. Although the synthesis and engineering of discrete molecular motors in the solution phase are well understood, the design and construction of motorized smart materials that operate at the supramolecular and macroscopic levels provide several fundamental challenges. This Review highlights emerging methodologies that take advantage of the supramolecular toolbox for the bottom-up assembly of responsive materials. Illustrative examples include muscle-like actuators, motor-based metal-organic frameworks, and motorized liquid crystal films and droplets. Emphasis is on how the light-responsive behavior and motion of rotary molecular motors can be communicated, delivered, and amplified to result in a specific dynamic output ranging from the nanoscale and molecular level all the way to the macroscopic scale and materials level. Furthermore, general guidelines for the supramolecular amplification of molecular motion and challenges and perspectives for the development of future motorized smart materials are presented.

CAD modeling for the components made of multi heterogeneous materials and smart materials

Abstract: There appear more critical requirements for special functions of components/products in various areas, which can be satisfied only by using heterogeneous materials and/or smart materials. The heterogeneous materials include composite materials, functionally graded materials, and heterogeneous materials with a periodic microstructure. To design and manufacture the components made of these materials, the computer models for representing them need first to be built so that further analysis, optimization and manufacturing can be implemented based on the models. This paper develops such a modeling method, which can be implemented by employing the functions of current CAD graphic software and obtain the model that includes all the material information (about periodic microstructures, constituent composition, inclusions, and embedded parts) along with geometry information in 3D solid modeling without the problem arising from too much data.