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.

Stress wave transmission and reflection through auxetic solids

Abstract: This paper establishes the effect of auxeticity on stress wave transmission and reflection. Specifically, investigation was made on wave transmission across two perfectly bonded isotropic solids in which the Poisson?s ratios ranged between ?1 and 0.5. The results show that the combined use of auxetic and conventional solids at extreme Poisson?s ratio is helpful to multiply or even to eliminate stress waves, under the prescribed density and modulus relations. These results suggest the usefulness of auxetic solids as smart materials and in smart structures for effective control of stress wave transmission.

Stimulation and reinforcement of shape-memory polymers and their composites: A review:

Abstract: Shape-memory polymers (SMPs) and their composites (SMPCs), as a kind of smart materials, can respond to particular external stimulus and recover the original shape They present outstanding feature

Piezocomposite transducers for smart structures applications

Abstract: This paper gives a summary on advanced piezocomposite transducers and the perspective of their applications in the field of smart structures, health monitoring and diagnostics. At present, three different low profile piezocomposite actuator types are commercially available. The designs are arising from the R&D work at MIT in the years 1991/92 funded by the US Department of Defence. Smart Material is manufacturing Macro Fiber Composites (MFC), licensed by NASA in a full-scale production. A new MFC- design using the 3-1 coupling has been developed, recently. It allows for the reduction of drive voltage down to 360 V. Fraunhofer IKTS focused its development on custom shape composites making use of PZT tubes and plates. New actuator devices for active interfaces have been introduced for the first time. All piezocomposite design forms show different performance data, which are summarised in the present paper to provide design engineers with necessary informations in view of intended applications.

Dynamic response analysis and vibration control of a cantilever beam with a squeeze-mode electrorheological damper

Abstract: Electrorheological (ER) fluids are a class of smart materials in which their rheological properties can be changed reversibly under the influence of an applied electric field. In recent years, many industrial applications of these smart fluids have been introduced by researchers, especially in the damping control of systems. In the present work, the applicability of squeeze-mode ER dampers in suppressing the vibration of a cantilever beam is investigated. The dynamic response of the beam for an impulse exciting force is obtained using a direct integration method based on a finite-element model for the structure. The nonlinear displacement and velocity-dependent characteristics of the squeeze-mode ER damper are considered in each of the iterations. Although the proposed ER damper has been found to have a significant influence on the dynamic response of the structure, adding a closed-loop control system could improve the damping behavior of the structure considerably. While the strength of the electric field depends on the gap between the electrodes, the control system uses displacement feedback for producing a controlling voltage to prevent the electric field exceeding its allowable bounds.

Microscopic investigation of the reasons for field-dependent changes in the properties of magnetic hybrid materials using X-ray microtomography

Abstract: Magnetic hybrid materials, i.e. materials containing magnetic particles as magnetoactive component in a non-magnetic matrix, can be controlled concerning their properties by means of moderate magnetic fields. The magnetic field-driven change in their properties is a result of the complex interaction of the magnetic particles and—in case of elastomers used as non-magnetic matrix—of the interaction of the particles with the surrounding matrix. These complex interactions are the major problem to achieve an understanding of magnetic hybrid materials on a level allowing tailored material production for certain application purposes. Such an understanding requires a scale bridging description of the material behaviour and of the resulting magnetically induced effects. In this context, the term scale bridging means that it is necessary to couple changes in the internal structure of a magnetic hybrid material, i.e. effects taking place on the scale of the magnetic particles, with macroscopic changes in its properties. Such a scale bridging understanding can not only be achieved on theoretical level. The complexity of the interparticle interaction and of the interaction of the particles with matrix as well as the vice versa coupling of both kind of interactions requires experimental data as input for theoretical approaches: moreover, such data provide a benchmark for respective predictions. Coupling magnetomechanical investigations on the macroscale with microscopic characterization using X-ray microtomography as a tool for a detailed visualization of the microstructure provides the required experimental approach to a scale bridging description of such smart materials. Within this paper, we will outline the required techniques for micro-and macroscopic investigations and will highlight the possibilities given by such an approach with a couple of examples.