Buy article PDF
The purchased file will be sent to you
via email after the payment is completed.
US$ 35
|
Smart Structures and Systems Volume 15, Number 6, June 2015 , pages 1521-1542 DOI: https://doi.org/10.12989/sss.2015.15.6.1521 |
|
|
|
Experimental analyses of dynamical systems involving shape memory alloys |
||
Soren Enemark, Marcelo A. Savi and Ilmar F. Santos
|
||
| Abstract | ||
| The use of shape memory alloys (SMAs) in dynamical systems has an increasing importance in engineering especially due to their capacity to provide vibration reductions. In this regard, experimental tests are essential in order to show all potentialities of this kind of systems. In this work, SMA springs are incorporated in a dynamical system that consists of a one degree of freedom oscillator connected to a linear spring and a mass, which is also connected to the SMA spring. Two types of springs are investigated defining two distinct systems: a pseudoelastic and a shape memory system. The characterisation of the springs is evaluated by considering differential calorimetry scanning tests and also force-displacement tests at different temperatures. Free and forced vibration experiments are made in order to investigate the dynamical behaviour of the systems. For both systems, it is observed the capability of changing the equilibrium position due to phase transformations leading to hysteretic behaviour, or due to temperature changes which also induce phase transformations and therefore, change in stiffness. Both situations are investigated by promoting temperature changes and also pre-tension of the springs. This article shows several experimental tests that allow one to obtain a general comprehension of the dynamical behaviour of SMA systems. Results show the general thermo-mechanical behaviour of SMA dynamical systems and the obtained conclusions can be applied in distinct situations as in rotor-bearing systems. | ||
| Key Words | ||
| shape memory alloys; dynamic systems; stiffness changes; phase transformation; experimental tests | ||
| Address | ||
| Soren Enemark and Ilmar F. Santos: Technical University of Denmark, Department of Mechanical Engineering, DK-2800 Kgs. Lyngby, Denmark Marcelo A. Savi: Universidade Federal do Rio de Janeiro, COPPE – Department of Mechanical Engineering, 21.941.972 – Rio de Janeiro – RJ – Brazil, P.O. Box 68.503 | ||