Search for: smart-composites
Article Proceedings of the ASME Conference on Smart Materials, Adaptive Structures and Intelligent Systems 2009, SMASIS2009, 21 September 2009 through 23 September 2009, Oxnard, CA ; Volume 1 , 2009 , Pages 641-647 ; 9780791848968 (ISBN) ; Mehdigholi, H ; Elahinia, M ; Sharif University of Technology
The shape memory alloys (SMAs) and smart composites have a large use in high and low level industry, while a lot of research is being done in this field. The existence of smart composite structures is because of the advance mechanical benefits of the above materials. This work refers to dynamic and quasi static nonlinear explanation of these materials. After mathematical model consideration on the rate of strain, a model which is about martensite ratio of NiTi has been presented. This work has been done because of the high sensitivity of these materials to strain rate and use of visual and measurable engineering criteria to access other variables. As the martensite ratio is not engineering...
Article Proceedings of the ASME Conference on Smart Materials, Adaptive Structures and Intelligent Systems 2009, SMASIS2009, 21 September 2009 through 23 September 2009, Oxnard, CA ; Volume 1 , 2009 , Pages 649-661 ; 9780791848968 (ISBN) ; Mehdigholi, H ; Elahinia, M ; Sharif University of Technology
This paper reviews the research results, characteristics, modeling and recent developments of smart materials specially shape memory alloys and smart composites. This field even involves smart fluids and it opens a new era to find new smart materials for eliminating their flaws by combination with other advanced materials. The purpose of this paper is showing the current research coordinate. These issues help to have a technological reference for these materials. At the end, there is specific attention to Nitinols and by experiments is shown that Oliver-Pharr formulation does not cover these material behaviors. These experiments cover some important aspects of Nitinols which have not been...
Modeling Magneto-Mechanical Behavior of Porous Magnetic Gel at Large Deformations in External Magnetic Field, M.Sc. Thesis Sharif University of Technology ; Naghdabadi, Reza
Magnetic gels and ferrogels are smart composite materials made by combining magnetic particles in a polymer matrix. These materials have been considered due to their special properties such as deformation and change of mechanical properties in the presence of external magnetic field. Having polymer properties along with the magnetic properties of metals, have led these materials to many uses such as drug delivery and artificial muscles. The increasing use of these materials has led researchers to continue research in the field of modeling ferrogels. Due to the porous nature of ferrogels, the ability to absorb a lot of liquid and their large deformations in the magnetic field, modeling of...
Article Proceedings of the ASME Conference on Smart Materials, Adaptive Structures and Intelligent Systems 2009, SMASIS2009, 21 September 2009 through 23 September 2009, Oxnard, CA ; Volume 2 , 2009 , Pages 141-148 ; 9780791848975 (ISBN) ; Mehdigholi, H ; Elahinia, M ; Sharif University of Technology
In this paper, one smart composite involving nitinol, piezoelectric and MMC is modeled. This simulation covers all criteria in these advanced materials and theoretically solves the five-order equation. Furthermore, numerical sample is investigated and results have been explored. The results represent the relationship between natural frequency of the structure, temperature, the lateral deflection and martensite ratio of shape memory alloy. The results show nonlinearity response in dynamic motion in lower natural frequency and linear behavior in higher frequency. In this simulation, numerical approximation has been avoided. Copyright © 2009 by ASME
Article Proceedings of the ASME Conference on Smart Materials, Adaptive Structures and Intelligent Systems 2009, SMASIS2009; 21 September 2009 through 23 September 2009 ; Volume 1 , 2009 , Pages 663-671 ; 9780791848968 (ISBN) ; Mehdigholi, H ; Elahinia, M ; Sharif University of Technology
This paper theoretically finds the different parameters of shape memory alloys via strain rate. Finite element formulation for temperature rate, and produced latent heat due to phase transition have been derived. Moreover, the equivalent viscous damp coefficient is provided. In addition, the Devonshire coefficient has been theoretically found by simplifications. This method helps to predict the heat and temperature change in quasi-static and dynamic studies in NiTi. Furthermore, they could be used in high nonlinear and low elastic deflection of NiTi. Then, the nonlinear vibration of smart composite involved with NiTi from any kind and percent of Ni and Ti could be handled by results....
Article Transactions of the Canadian Society for Mechanical Engineering ; Volume 35, Issue 3 , 2011 , Pages 369-381 ; 03158977 (ISSN) ; Zabihollah, A ; Sharif University of Technology
In this paper, a nonlinear Finite Element (FE) approach based on the layerwise displacement theory is utilized to obtain the interlaminar stresses due to buckling phenomena in unsymmetric laminated smart composite morphing structure. An On/Off control strategy is designed to control the snap-through phenomena. Due to cycling nature of applied load on morphing, these structures are vulnerable to failure due to fatigue. A failure control mechanism utilizing a piezoelectric actuator is developed to control the failure
Article Materials and Design ; Volume 30, Issue 9 , 2009 , Pages 3667-3672 ; 02641275 (ISSN) ; Hassanzadeh Nemati, N ; Bagheri, R ; Sharif University of Technology
Recent uses of intelligent composites in biomedical appliances aggrandize the necessity of bonding-strength improvement in NiTi/silicone matrix interface. SEM micrographs and pull-out tests are employed to determine the strength of the NiTi/silicone bonds in a flexible composite piece. Greater adhesion strengths are obtained due to the presence of thin oxide layer, surface roughness and frictional forces between the embedded-wires and the contacting phase. Effect of curing treatment on phase transformation temperatures of the wires is determined by electrical resistivity (ER) measurements. Results show that the curing treatment shifts the transition points of the wires towards higher...