Thermomechanical Characterization of Shape Memory Alloy Tubular Composite Structures

2008 ◽  
Vol 59 ◽  
pp. 150-155 ◽  
Author(s):  
Ludek Heller ◽  
D. Vokoun ◽  
D. Majtás ◽  
Petr Šittner
Keyword(s):  
Shape Memory Alloy ◽  
Composite Structures ◽  
Industrial Applications ◽  
Thermomechanical Properties ◽  
Tubular Structures ◽  
Static Properties ◽  
Wide Range ◽  
Niti Wires ◽  
Composite Samples

Currently, thin NiTi wires have been considered for producing knitted and woven smart textiles with anticipated unique thermomechanical properties promising a wide range of new industrial applications. We propose a concept of NiTi tubular composite structures which enhances functional properties of single NiTi wires and offers new possibilities of their use. Such possibilities are provided by the combination of SMA properties with the geometrical architecture and properties of polymers incorporated into the tubular structures. Our study deals with the manufacture of the NiTi tubular composite structures and their thermomechanical properties under a uniaxial loading. Quasi-static properties and the strain-rate dependence are investigated in tension. We propose a way of producing novel SMA tubular composite structures. The designed composite samples exhibit thermomechanical properties characterized by the thermomechanical interaction between a NiTi tubular structure and incorporated polymers.

Vibration Characteristics of Composite Plate Embedded with Shape Memory Alloy at Elevated Temperature

2013 ◽  
Vol 393 ◽  
pp. 655-660 ◽  
Author(s):  
Izzuddin Zaman ◽  
Bukhari Manshoor ◽  
Amir Khalid ◽  
Sherif Araby ◽  
Mohd Imran bin Ghazali
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Composite Structures ◽  
Composite Plate ◽  
Free Vibration Analysis ◽  
Composite Plates ◽  
Vibration Characteristics ◽  
Modal Testing ◽  
Phase Transformation Temperature ◽  
Wide Range

Unique functional material of shape memory alloy has attracted tremendous interest from researches, thus has been broadly investigated for a wide range application. Current research effort extends the use of SMA for the design of smart composite structures due to its shape memory effect, pseudo-elasticity and high damping capability. This paper presents an assessment of applications of the SMA materials for structural vibration controls, where the influences of SMA as reinforcement in the composite plate at different temperature are investigated. Four cases of composite plate are studied, which two of them are SMA-based composite fabricated at 0° and 45° angles, and the other two plates are neat (without SMA wires) and built with local stiffener. By using modal testing, the free vibration analysis is carried out to determine the vibration characteristics of composite plates. The results show that infusing SMA wires into composites increased the natural frequencies of the plate considerably, while decreased slightly for damping percentage. However, when SMA wires are heated, the damping percentage improved tremendously due to the phase transformation temperature of SMA from martensite to austenite. The outcome of this study reveals the potential of SMA materials in active vibration control.

Numerical implementation of the microplane constitutive model for shape memory alloys

2017 ◽  
Vol 233 (6) ◽  
pp. 1117-1133 ◽  
Author(s):  
MR Karamooz-Ravari ◽  
B Shahriari
Keyword(s):  
Shape Memory Alloy ◽  
Constitutive Model ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Numerical Integration ◽  
Biological Properties ◽  
Industrial Applications ◽  
Stress Increment ◽  
Integration Formulas

With the advent of shape memory alloys, several industrial applications were proposed due to their superior mechanical and biological properties. Since the fabrication and characterization of shape memory alloy devices is challenging and expensive, it is necessary to simulate their thermomechanical responses before fabrication. To do so, a powerful constitutive model capable of simulation of the important features of these materials is necessary. To be able to simulate a shape memory alloy device, it is vital to implement a suitable constitutive model in such a way to be used in finite element models. In this paper, an existing constitutive model based on microplane theory is numerically implemented and the effects of stress increment, different numerical integration formulas, and loading direction on the thermomechanical response of shape memory alloy is investigated through superelastic and shape memory proportional and nonproportional loadings. The obtained results show that the stress increment may have significant effect on the results if the forward Euler scheme is utilized. In addition, for the case of numerical integration over the surface of a unit hemisphere, 61 points integration formula without orthogonal symmetry provides the best results while 21 orthogonally symmetric one is the most inaccurate one. Also, the orthogonally symmetric numerical integration formulas predict the isotropic material response while those without orthogonal symmetry predict a little anisotropy.

scholarly journals Electrical characterization of poly(vinylidene fluoride-trifluoroethylene) nanocrystals embedded in porous alumina matrix

2018 ◽  
Vol 08 (01) ◽  
pp. 1820001 ◽  
Author(s):  
A. N. Belov ◽  
I. L. Kislova ◽  
D. V. Loktev ◽  
E. N. Redichev ◽  
A. A. Stroganov ◽  
...  
Keyword(s):  
Composite Structures ◽  
Vinylidene Fluoride ◽  
Porous Alumina ◽  
Electrical Characterization ◽  
Dielectric Characteristics ◽  
Porous Aluminum ◽  
Poly Vinylidene Fluoride ◽  
Melt Impregnation ◽  
Composite Samples

In this work, the study of dielectric properties of composite structures on the base of poly(vinylidene fluoride-triflouroethylene) copolymer P(VDF-TrFE) and porous aluminum oxide layers produced by the melt-impregnation is presented. Frequency dependences of dielectric characteristics of the composite samples were determined. The dielectric dispersion and ferroelectric switching processes in the composite structures were discussed.

Active Moving Polymers and Multifunctional Composites: Shape the Future Structures

2013 ◽  
Vol 745 ◽  
pp. 129-134 ◽  
Author(s):  
Jin Song Leng
Keyword(s):  
Smart Materials ◽  
Biomedical Engineering ◽  
Composite Structures ◽  
Shape Memory Polymer ◽  
Multifunctional Composites ◽  
Deployable Structures ◽  
Wide Range ◽  
Space Deployable Structures ◽  
Short Carbon

Smart materials can be defined as the materials that have the capability of sensing and reacting to environmental conditions or stimuli. In recent years, a wide range of novel smart materials have been developed, the applications of which now cover various important fields including aerospace, automobile, telecommunications, and so forth. This talk mainly focuses on recent progresses of Active Moving Polymer (i.e. Shape Memory Polymer, SMP), and SMP based composite structures, as well as their applications including aerospace, astronautics and biomedical engineering. This presented work summarizes the recent advances in novel SMP including epoxy-based SMP, styrene-based SMP, cyanate ester-based SMP, polyurethane-based SMP, multiple SMP, design and characterization of SMP composites (SMPCs) filled with nickel chains, short carbon fiber, carbon nanotube chains, carbon nanopaper, and so on. The SMP stimulus methods, including heat, electric, light, magnetic field, and solvent have been introduced. The application of SMPCs used in aircraft morphing and space deployable structures is also investigated.

scholarly journals Design, Manufacturing, and Characterization of Hybrid Carbon/Hemp Sandwich Panels

2021 ◽  
Author(s):  
Luca Boccarusso ◽  
Fulvio Pinto ◽  
Stefano Cuomo ◽  
Dario De Fazio ◽  
Kostas Myronidis ◽  
...  
Keyword(s):  
Composite Structures ◽  
Failure Modes ◽  
Sandwich Panels ◽  
Industrial Applications ◽  
Low Velocity Impact ◽  
Sandwich Composite ◽  
Continuous Manufacturing ◽  
Low Velocity ◽  
Impact Compression

AbstractAdvanced sandwich composite structures that incorporate foams or honeycombs as core materials, have been extensively investigated and used in various applications. One of the major limitations of the conventional materials used is their weak impact resistance and their end-of-life recyclability and overall sustainability. This paper is focused on the study of the production and mechanical characterization of hybrid sandwich panels using hemp bi-grid cores that were manufactured with an ad hoc continuous manufacturing process. Bi-grid structures were stratified in multiple layers, resulting in cores with different thicknesses and planar density. Sandwich panels made with carbon fibers skins were then subjected to Low Velocity Impact, compression and indentation and the damaged panels were investigated via CT-Scan. Results show that the high tailorability of the failure modes and the very good energy absorption properties of the hybrid material open new exciting perspectives for the development of new sandwich structures that can extend the use of natural fibers into several industrial applications.

Development and auxetic characterization of 3D composites produced with newly-designed multi-cell flat-knitted spacer fabrics

2020 ◽  
pp. 152808372097169
Author(s):  
Zahra Moshtaghian ◽  
Hossein Hasani ◽  
Mohammad Zarrebini ◽  
Mohammad Pourheidar Shirazi
Keyword(s):  
Poisson’S Ratio ◽  
Composite Structures ◽  
Compressive Strain ◽  
Poisson's Ratio ◽  
Initial Slope ◽  
Displacement Curve ◽  
3D Composite ◽  
Spacer Fabrics ◽  
Composite Samples

The paper deals with development and characterization of 3D sandwich composite structures reinforced with newly-designed multi-cell flat-knitted spacer fabrics in terms of compressive behaviour and Poisson’s ratio. Multi-cell spacer knitted preforms was produced on a computerized flat knitting machine. 3D composite samples with three different cross-sectional geometries were prepared via vacuum assisted resin transfer moulding method. Quasi-static compressive experiments were carried out on the prepared 3D composite samples. The Poisson’s ratio of re-entrant 3D knitted composite varied between -6 and -1, which clearly points to existence of auxetic behaviour of the samples. The re-entrant 3D composites also demonstrated the highest initial slope and area under the compression force-displacement curve than spear-head or hexagonal composite structures which refer to higher energy absorbing capacity. The Poisson’s ratio of 3D regular hexagonal knitted composites at small strain was usually 4 which gradually decreased to 1.6 as the exerted compressive strain increased. Additionally, 3D spear-head knitted composite having zero Poisson’s ratio was also developed.

Mineralogical and crystal-chemical characterization of the talc ore deposit of Minzanzala, Gabon

Clay Minerals ◽  
2019 ◽  
Vol 54 (3) ◽  
pp. 245-254
Author(s):  
Mathilde Poirier ◽  
Jean-Eudes Boulingui ◽  
François Martin ◽  
Michel Mbina Mounguengui ◽  
Charles Nkoumbou ◽  
...  
Keyword(s):  
Chemical Characterization ◽  
Spectroscopic Characterization ◽  
Industrial Applications ◽  
Crystal Chemical ◽  
X Ray Diffraction ◽  
Wide Range ◽  
Two Samples ◽  
Fe Oxyhydroxides ◽  
Chemical Purity

AbstractThis research aims to characterize the mineralogical and crystal-chemical purity of two samples of natural talc (BTT6, BTT7) from the occurrence ‘Ecole1’ in the deposit of Minzanzala, southwest Gabon. X-ray diffraction and modal-composition calculations demonstrated the presence of quartz and Al–Fe-bearing phases (kaolinite and/or chlorite and/or Al–Fe oxyhydroxides) as accessory minerals in both ores. In contrast, the chemical and spectroscopic characterization of the talc component revealed remarkable chemical purity expressed by very low Fe contents. According to these results, the talc of Minzanzala might be used as a filler in a wide range of industrial applications, such as in cosmetics, paints, polymers or ceramics.

scholarly journals Low-Cost Synthesis and Characterization of Silver Nanoparticles for Diverse Sensing Application

2019 ◽  
Vol 9 (2) ◽  
pp. 3915-3917
Author(s):  
S. Akhtar ◽  
Z. Farid ◽  
H. Ahmed ◽  
S. A. Khan ◽  
Z. N. Khan
Keyword(s):  
Silver Nanoparticles ◽  
Chemical Reduction ◽  
Low Cost ◽  
Industrial Applications ◽  
X Ray Diffraction ◽  
Ag Nps ◽  
X Ray ◽  
Wide Range ◽  
Range Of Functions

Silver (Ag) nanoparticles (NPs) are synthesized and characterized by a low-cost chemical reduction method. Silver nanoparticles (Ag NPs) have pre-occupied the consideration of the scientific community due to their wide range of functions, utility and industrial applications, particularly in the fields of sensing technologies and medicine (particularly their efficiency against microbes, the ability of healing the wound and anti-inflammatory properties). Ag NPs are synthesized by a low-cost fabrication method. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray diffraction (EDX) and photometry techniques are used in this work to identify their nature and potentiality for diverse applications in sensing technologies.

TESTING DEVICE FOR CHARACTERIZATION OF THE THERMOMECHANICAL PROPERTIES OF A SHAPE MEMORY ALLOY ACTUATOR

2015 ◽  
Author(s):  
David Domingos Soares da Silva ◽  
Ewerton Freitas de Medeiros ◽  
Lipson Douglas de Oliveira Silva ◽  
Melquisedeque Shaloon Bento da Silva Gomes ◽  
Alysson Domingos Silvestre ◽  
...  
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Thermomechanical Properties ◽  
Testing Device ◽  
Shape Memory Alloy Actuator
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