Shape Memory Microactuators
Title | Shape Memory Microactuators PDF eBook |
Author | Manfred Kohl |
Publisher | Springer Science & Business Media |
Pages | 265 |
Release | 2013-03-09 |
Genre | Technology & Engineering |
ISBN | 366209875X |
Overview of recent achievements, describing the microactuator development of microvalves and liner actuators comprehensively from concept through prototype. Further key aspects included are three-dimensional models for handling complex SMA actuator geometries and coupled simulation routines that take multifunctional properties into account. Mechanical and thermal optimization criteria are introduced for actuator design, allowing an optimum use of the shape memory effect. It is shown that some of the prototypes presented, e.g. SMA microgrippers, already outperform conventional components.
Composition, Structure and Magneto-mechanical Properties of Ni-Mn-Ga Magnetic Shape-memory Alloys
Title | Composition, Structure and Magneto-mechanical Properties of Ni-Mn-Ga Magnetic Shape-memory Alloys PDF eBook |
Author | Markus Chmielus |
Publisher | Logos Verlag Berlin |
Pages | 0 |
Release | 2010 |
Genre | |
ISBN | 9783832525316 |
Magnetic shape-memory alloys (MSMAs) are smart materials which show in single crystalline form a magnetic field induced plastic and recoverable deformation of up to 10 %. Ni-Mn-Ga is the as most prominent representative. The shape change of MSMAs is based on the motion of twin boundaries driven by a magneto-stress due to an applied magnetic field. The plastic deformation takes place in the martensite phase and does not require a phase change as needed in shape-memory alloys (SMAs). The combination of high strain of SMAs and high actuation frequencies positions MSMAs as attractive smart actuator materials. Several aspects influence the magneto-mechanical properties. To identify the influence of composition, surface deformation, and constraints separately, this dissertation consists of three parts: first, the characterization of composition, structure, transformation temperatures, magnetic and mechanical properties as a study on position within an ingot. Second, the influence of surface polishing and surface deformation on the twinning stress. Third, the influence of training and constraints on magneto-mechanical properties. It can be shown in this work that each of the investigated aspects has strong influences on i.e. martensite structure and transformation temperatures, twinning stresses, twin microstructure, and magneto-mechanical properties of MSMAs.
International Conference on Martensitic Transformations (ICOMAT) 2008
Title | International Conference on Martensitic Transformations (ICOMAT) 2008 PDF eBook |
Author | Gregory Olson |
Publisher | John Wiley & Sons |
Pages | 1617 |
Release | 2013-10-09 |
Genre | Technology & Engineering |
ISBN | 1118804147 |
During the week of June 29 - July 5, 2008, over 300 scientists and engineers from 30 countries spanning five continents converged at the historic La Fonda Hotel in the city of Santa Fe, New Mexico, USA to participate in the 12th International Conference on Martensitic Transformations (ICOMAT-08) to fathom the peculiar world of certain crystalline materials that undergo structural change when cooled or stressed. Many of these materials can restore their original shape when reheated, thus the name "Shape Memory Alloys". In the spirit of Santa Fe, a central theme of ICOMAT-08 was INTEGRATION across many dimensions.
Magnetic Shape Memory Alloys
Title | Magnetic Shape Memory Alloys PDF eBook |
Author | Xuexi Zhang |
Publisher | Springer Nature |
Pages | 273 |
Release | 2021-11-14 |
Genre | Technology & Engineering |
ISBN | 981166336X |
This book systematically describes the fundamentals of Magnetic shape memory alloys (MSMAs), with an emphasis on low-dimensional structures such as foams, microwires and micro-particles. The respective chapters address basic concepts and theories, the fabrication of various architectures, microstructure tailoring, property optimization and cutting-edge applications. Taken together, they provide a clear understanding of the correlation between processing and the microstructural properties of MSMAs, which are illustrated in over two hundred figures and schematics. Given its scope and format, the book offers a valuable resource for a broad readership in various fields of materials science and engineering, especially for researchers, students and engineers.
Shape-Memory Alloys Handbook
Title | Shape-Memory Alloys Handbook PDF eBook |
Author | Christian Lexcellent |
Publisher | John Wiley & Sons |
Pages | 295 |
Release | 2013-04-08 |
Genre | Technology & Engineering |
ISBN | 1118577957 |
The aim of this book is to understand and describe the martensitic phase transformation and the process of martensite platelet reorientation. These two key elements enable the author to introduce the main features associated with the behavior of shape-memory alloys (SMAs), i.e. the one-way shape-memory effect, pseudo-elasticity, training and recovery. Attention is paid in particular to the thermodynamical frame for solid materials modeling at the macroscopic scale and its applications, as well as to the particular use of such alloys – the simplified calculations for the bending of bars and their torsion. Other chapters are devoted to key topics such as the use of the “crystallographical theory of martensite” for SMA modeling, phenomenological and statistical investigations of SMAs, magneto-thermo-mechanical behavior of magnetic SMAs and the fracture mechanics of SMAs. Case studies are provided on the dimensioning of SMA elements offering the reader an additional useful framework on the subject. Contents 1. Some General Points about SMAs. 2. The World of Shape-memory Alloys. 3. Martensitic Transformation. 4. Thermodynamic Framework for the Modeling of Solid Materials. 5. Use of the “CTM” to Model SMAs. 6. Phenomenological and Statistical Approaches for SMAs. 7. Macroscopic Models with Internal Variables. 8. Design of SMA Elements: Case Studies. 9. Behavior of Magnetic SMAs. 10. Fracture Mechanics of SMAs. 11. General Conclusion. Appendix 1. Intrinsic Properties of Rotation Matrices. Appendix 2. “Twinning Equation” Demonstration. Appendix 3. Calculation of the Parameters a, n and Q from the “Twinning” Equation. Appendix 4. “Twinned” Austenite/Martensite Equation. About the Authors Christian Lexcellent is Emeritus Professor at the École National Supérieure de Mécanique et des Microtechniques de Besançon and a researcher in the Department of Applied Mechanics at FEMTO-ST in France. He is a specialist in the mechanics of materials and phase transition and has taught in the subjects of mechanics of continuum media and shape memory alloys. He is also a member of the International Committee of ESOMAT.
Nanoscale Magnetic Materials and Applications
Title | Nanoscale Magnetic Materials and Applications PDF eBook |
Author | J. Ping Liu |
Publisher | Springer Science & Business Media |
Pages | 731 |
Release | 2010-04-05 |
Genre | Science |
ISBN | 0387856005 |
Nanoscale Magnetic Materials and Applications covers exciting new developments in the field of advanced magnetic materials. Readers will find valuable reviews of the current experimental and theoretical work on novel magnetic structures, nanocomposite magnets, spintronic materials, domain structure and domain-wall motion, in addition to nanoparticles and patterned magnetic recording media. Cutting-edge applications in the field are described by leading experts from academic and industrial communities. These include new devices based on domain wall motion, magnetic sensors derived from both giant and tunneling magnetoresistance, thin film devices in micro-electromechanical systems, and nanoparticle applications in biomedicine. In addition to providing an introduction to the advances in magnetic materials and applications at the nanoscale, this volume also presents emerging materials and phenomena, such as magnetocaloric and ferromagnetic shape memory materials, which motivate future development in this exciting field. Nanoscale Magnetic Materials and Applications also features a foreword written by Peter Grünberg, recipient of the 2007 Nobel Prize in Physics.
Design of Shape Memory Alloy (SMA) Actuators
Title | Design of Shape Memory Alloy (SMA) Actuators PDF eBook |
Author | Ashwin Rao |
Publisher | Springer |
Pages | 137 |
Release | 2015-05-08 |
Genre | Science |
ISBN | 3319031880 |
This short monograph presents an analysis and design methodology for shape memory alloy (SMA) components such as wires, beams, and springs for different applications. The solid-solid, diffusionless phase transformations in thermally responsive SMA allows them to demonstrate unique characteristics like superelasticity and shape memory effects. The combined sensing and actuating capabilities of such materials allows them to provide a system level response by combining multiple functions in a single material system. In SMA, the combined mechanical and thermal loading effects influence the functionality of such materials. The aim of this book is to make the analysis of these materials accessible to designers by developing a "strength of materials" approach to the analysis and design of such SMA components inspired from their various applications with a review of various factors influencing the design process for such materials.