Download or read book Shape Memory Microactuators written by Manfred Kohl and published by Springer. This book was released on 2010-12-04 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Thin Film NiTi Shape Memory Alloy Microactuators written by John J. Gill and published by . This book was released on 2001 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Shape Memory Alloy Actuators written by Mohammad H. Elahinia and published by John Wiley & Sons. This book was released on 2015-11-25 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a systematic approach to realizing NiTi shape memory alloy actuation, and is aimed at science and engineering students who would like to develop a better understanding of the behaviors of SMAs, and learn to design, simulate, control, and fabricate these actuators in a systematic approach. Several innovative biomedical applications of SMAs are discussed. These include orthopedic, rehabilitation, assistive, cardiovascular, and surgery devices and tools. To this end unique actuation mechanisms are discussed. These include antagonistic bi-stable shape memory-superelastic actuation, shape memory spring actuation, and multi axial tension-torsion actuation. These actuation mechanisms open new possibilities for creating adaptive structures and biomedical devices by using SMAs.
Download or read book Thin Film Shape Memory Alloys written by Shuichi Miyazaki and published by Cambridge University Press. This book was released on 2009-09-03 with total page 487 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first dedicated book describing the properties, preparation, characterization and device applications of TiNi-based shape memory alloys.
Download or read book TiNi Shape Memory Alloy Thin Film Rotating Micro actuators written by Cho Chiu Ma and published by . This book was released on 1999 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of Microactuators Based on the Magnetic Shape Memory Effect written by Yeduru, Srinivasa Reddy and published by KIT Scientific Publishing. This book was released on 2013-12-10 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: The giant magneto-strain effect in Ni-Mn-Ga alloys is particularly attractive for actuator applications. Two different approaches are being pursued to develop MSM microactuators. To observe large deflections of Ni-Mn-Ga microactuators, the material should be exhibiting low twinning stress and large magnetic anisotropy. In addition, design rules and boundary conditions for operating the Ni-Mn-Ga actuator material are having significant importance for evolution of performance characteristics.
Download or read book A New Mechanical Characterization Method for Thin Film Microactuators and Its Application to NiTiCi Shape Memory Alloy written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In an effort to develop a more full characterization tool of shape memory alloys, a new technique is presented for the mechanical characterization of microactuators and applied to SMA thin films. A test instrument was designed to utilize a spring-loaded transducer in measuring displacements with resolution of 1.5 pm and forces with resolution of 0.2 mN. Employing an out-of-plane loading method for freestanding SMA thin films, strain resolution of 30[mu][epsilon] and stress resolution of 2.5 MPa were achieved. This new testing method is presented against previous SMA characterization methods for purposes of comparison. Four mm long, 2 [mu]m thick NiTiCu ligaments suspended across open windows were bulk micromachined for use in the out-of-plane stress and strain measurements. The fabrication process used to micromachine the ligaments is presented step-by-step, alongside methods of fabrication that failed to produce testable ligaments. Static analysis showed that 63% of the applied strain was recovered while ligaments were subjected to tensile stresses of 870 MPa. In terms of recoverable stress and recoverable strain, the ligaments achieved maximum recovery of 700 MPa and 3.0% strain. No permanent deformations were seen in any ligament during deflection measurements. Maximum actuation forces and displacements produced by the 4 mm ligaments situated on 1 cm square test chips were 56 mN and 300 [mu]m, respectively. Fatigue analysis of the ligaments showed degradation in recoverable strain from 0.33% to 0.24% with 200,000 cycles, corresponding to deflections of 90 [mu]m and forces of 25 mN. Cycling also produced a wavering shape memory effect late in ligament life, leading to broad inconsistencies of as much as 35% deviation from average. Unexpected phenomena like stress-induced martensitic twinning that leads to less recoverable stress and the shape memory behavior of long life devices are addressed. Finally, a model for design of microactuators using shape memory alloys is presented to illustrate how results obtained from these tests can be interpreted and applied to the creation of MEMS devices.
Download or read book Shape Memory Alloy Microactuators written by and published by . This book was released on 2004 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NiTi Shape Memory Alloy Thin Film Based Microgripper written by Jun Ping Tan and published by . This book was released on 2001 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A New Mechanical Characterization Method for Thin Film Microactuators and Its Application to NiTiCu Shape Memory Alloy written by Kirk Patrick Seward and published by . This book was released on 1999 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fabrications of Shape Memory Alloy Thin Films and NiTi Microvalves Based on Micro Electro Mechanical System MEMS Techniques written by 尤良 and published by . This book was released on 2004 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of Nano Structured Thin Film Shape Memory Alloys for MEMS Applications written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The production of thin film TiPdNi shape memory alloys (SMA) using ion beam assisted deposition (IBAD) is being studied as a way to increase the actuation frequencies and transformation temperatures of thin film SMA for micro-actuator applications. The capability to transmit extremely high forces along with a large stroke, large strain memory, and high corrosion resistance makes shape memory alloys prime candidates for use in micro-actuator applications. However, low actuation frequency (~1Hz at macro-scale), and low transition temperature (below 100°C) makes commercially available NiTi incompatible with applications in extreme environments. The transformation temperature and actuation frequency of shape memory alloys can be improved through the production of thin film TiPdNi. Through the substitution of Pd for Ni in equiatomic NiTi, the transformation temperature can be varied from approximately room temperature to 527°C. The composition that has received the most attention is Ti50Pd30Ni20 because of its transformation temperature of over 200°C. However, the shape memory effect of Ti50Pd30Ni20 is adversely affected by the low critical stress needed for slip at high temperatures, which results in unrecoverable strain. Age hardening or thermo-mechanical treatments such as cold rolling have been found to improve the critical stress for slip in bulk form SMA due to an increased density of dislocations. Precipitation hardening, as well as, ion bombardment, is expected to increase the high temperature properties in IBAD deposited Ti50Pd30Ni20 film SMA. Additionally, ion bombardment during deposition can be used to improve film properties such as morphology, density, stress level, crystallinity, as well as, limit defects. Due to the refined grain size, increased density, and reduced defects, IBAD is able to produce films of 1 micron or less, which will greatly reduces the SMA actuation time due to the increased surface area --to -- volume ratio. In t.
Download or read book Preparation of Shape memory alloy thin Film for Actuator written by Cengling Zhang and published by . This book was released on 2001 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Introduction to Micromechanisms and Microactuators written by Amitabha Ghosh and published by Springer. This book was released on 2015-01-20 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a basic introduction to micromechanisms and microactuators, particularly to their basic configurations and design. This book fills the persisting gap in the published literature on the mechanical manipulative aspects of micromechanisms. It also helps in offering specialized introductory courses on micromechanisms and microactuators not as part of MEMS sensing devices, but as mechanical manipulative systems. The level of the book is suitable for use in both undergraduate and introductory graduate programmes. The book presents an overview of miniaturization and scaling laws, basic design principles of micro-sized mechanisms and actuators, micro-fabrication processes, and some futuristic issues. The volume contains a large number of figures and illustrations for easy understanding by the readers. It will also be useful to researchers and professionals looking for an introduction to the topic.
Download or read book Shape Memory Alloys for Small Scale Actuation written by Ashley Jessica Hartwell and published by . This book was released on 2018 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shape Memory Alloys (SMAs), materials that can undergo a fully recoverable strain change due to a thermal cycle, and which can be produced in a form that is superelastic are only utilized limitedly. In this thesis, I investigated the relationship between the material properties of shape memory alloy micro-wires and their mechanical performance. This study was conducted with two main types of SMAs, the first a commercially available NiTi wire, and the second an emerging Cu-based alternative. This comparison allows an understanding of the current state of the art for small scale actuation with SMA wires, and to evaluate the Cu-based alternative SMA, which has a reduced cost and improved thermal properties. This thesis evaluates Cu-based SMAs as substitutes for NiTi in terms of activation strain of wire during a shape memory cycle, power consumption during actuation, heating and cooling times during actuation, and cost. Furthermore this thesis includes studies on the processing of Cu-based alternatives to enhance shape memory properties of interests, such as transformation temperature and fatigue, and suggests future work to improve Cu-based SMA wires..
Download or read book Optimization of MEMS Actuator Driven by Shape Memory Alloy Thin Film Phase Change written by Cory R. Knick and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: At the microscale, shape memory alloy (SMA) microelectromechanical system (MEMS) bimorph actuators offer great potential based on their inherently high work density. An optimization problem relating to the deflection and curvature based on shape memory MEMS bimorph was identified, formulated, and solved. Thicknesses of the SU-8 photoresist and nickel-titanium alloy (NiTi) was identified that yielded maximum deflections and curvature radius based on a relationship among individual layer thicknesses, elastic modulus, and cantilever length. This model should serve as a guideline for optimal NiTi and SU-8 thicknesses to drive large deflections and curvature radius that are most suitable for microrobotic actuation, micromirrors, micropumps, and microgrippers. This model would also be extensible to other phase-change-driven actuators where nonlinear and significant residual stress changes are used to drive actuation.
Download or read book Shape Memory Alloy Micro actuators for Bio medical Applications written by Sheng Long Mao and published by . This book was released on 2003 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
